CN116709669A - Manufacturing method of circuit board external connection bridging stacking structure - Google Patents
Manufacturing method of circuit board external connection bridging stacking structure Download PDFInfo
- Publication number
- CN116709669A CN116709669A CN202211729086.2A CN202211729086A CN116709669A CN 116709669 A CN116709669 A CN 116709669A CN 202211729086 A CN202211729086 A CN 202211729086A CN 116709669 A CN116709669 A CN 116709669A
- Authority
- CN
- China
- Prior art keywords
- bonding pad
- fpc
- pad position
- circuit board
- manufacturing
- 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.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- 229910000679 solder Inorganic materials 0.000 claims abstract description 26
- 239000011889 copper foil Substances 0.000 claims abstract description 22
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 21
- 238000005476 soldering Methods 0.000 claims abstract description 18
- 239000000758 substrate Substances 0.000 claims abstract description 15
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 6
- 238000005516 engineering process Methods 0.000 claims abstract description 6
- 238000007650 screen-printing Methods 0.000 claims abstract description 6
- 239000010959 steel Substances 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims description 16
- 238000003466 welding Methods 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- 230000004907 flux Effects 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 238000004321 preservation Methods 0.000 claims description 3
- 239000004094 surface-active agent Substances 0.000 claims description 3
- 239000013008 thixotropic agent Substances 0.000 claims description 3
- 239000000843 powder Substances 0.000 claims description 2
- -1 flux Substances 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 235000011837 pasties Nutrition 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
- 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
- H05K3/4614—Manufacturing multilayer circuits by laminating two or more circuit boards the electrical connections between the circuit boards being made during lamination
-
- 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
- H05K3/4038—Through-connections; Vertical interconnect access [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
- H05K3/46—Manufacturing multilayer circuits
- H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
- H05K3/4623—Manufacturing multilayer circuits by laminating two or more circuit boards the circuit boards having internal via connections between two or more circuit layers before lamination, e.g. double-sided circuit boards
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Abstract
The invention discloses a manufacturing method of an external connection bridging structure of a circuit board, which comprises the steps of obtaining a double-sided circuit PCB device surface, and determining a first bonding pad position and a second bonding pad position on the PCB device surface; acquiring an FPC, wherein the FPC comprises a substrate layer and a copper foil layer, the copper foil layer is attached to the substrate layer, two ends of the FPC are provided with through holes, and the through holes penetrate through the substrate layer and the copper foil layer; placing solder paste on the first bonding pad position and the second bonding pad position by using steel screen printing; mounting the first bonding pad and the second bonding pad on two ends of the FPC in an SMT (surface mount technology) surface mount mode; and (3) dialyzing the solder paste from the through hole by adopting a reflow soldering mode and soldering the solder paste with the through hole, so that two ends of the FPC are soldered on the first bonding pad position and the second bonding pad position. The invention improves the design mode of the product, reduces the number of layers of the product and saves the cost; good circuit logic is achieved through the principle mode of external bridging; the overlap joint adopts external FPC's type, through SMT welded mode, improves the reliability of fixed bridging.
Description
Technical Field
The invention relates to the technical field of rigid-flexible boards, in particular to a manufacturing method of an external connection bridging structure of a circuit board.
Background
As technology advances, the demands on the circuit board are also increasing. At present, the OLED circuit board is formed by stacking 4-6 layers of soft and hard boards, and the existing multilayer board lamination mode adopts a hot pressing technology, so that some problems exist: the bonding pad is small, the pressure is large, and short circuit is easy to cause. The TP and the display function share the same circuit board, and the structure is smaller by more than 3 layers because the product network logic reaches up to 560 groups.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a manufacturing method of an external connection bridging structure of a circuit board, and good circuit logic is achieved by a principle mode of external connection bridging; the overlap joint adopts external FPC's type, through SMT welded mode, improves the reliability of fixed bridging.
The invention discloses a manufacturing method of an external connection bridging structure of a circuit board, which comprises the following specific steps:
acquiring a double-sided circuit PCB device surface, and determining a first bonding pad position and a second bonding pad position on the PCB device surface;
acquiring an FPC, wherein the FPC comprises a substrate layer and a copper foil layer, the copper foil layer is attached to the substrate layer, two ends of the FPC are provided with through holes, and the through holes penetrate through the substrate layer and the copper foil layer;
placing solder paste on the first bonding pad position and the second bonding pad position by using steel screen printing;
mounting the first bonding pad and the second bonding pad on two ends of the FPC in an SMT (surface mount technology) surface mount mode;
and (3) dialyzing the solder paste from the via hole and welding the solder paste with the via hole by adopting a reflow welding mode, so that two ends of the FPC are welded on the first bonding pad position and the second bonding pad position.
Further, according to the manufacturing method of the circuit board external connection bridging stacking structure, the FPC is arranged on the surface of the PCB device, and the size of the FPC is 10% -45% of that of the surface of the PCB device.
Further, in the manufacturing method of the circuit board external connection bridging stacking structure, the FPC and the test pad on the surface of the PCB device are arranged in a staggered mode.
Further, according to the manufacturing method of the circuit board external connection bridging stacking structure, the FPC is a single-sided circuit, and the FPC comprises 25 groups of network logics.
Furthermore, in the manufacturing method of the circuit board external connection bridging structure, the first bonding pad position and the second bonding pad position are respectively provided with a plurality of bonding pads, and the size of each bonding pad is 0.35mm.
Further, in the manufacturing method of the circuit board external connection bridging structure, the line distance between the bonding pads is 0.15mm.
Furthermore, in the manufacturing method of the circuit board external connection bridging structure, the size of the through hole is 0.1mm.
Further, according to the manufacturing method of the circuit board external connection bridging stacking structure, the FPC comprises two copper foil layers, the two copper foil layers are respectively attached to two sides of the base material, and a through hole penetrating through the base material layer is connected between the two copper foil layers.
Further, in the method for manufacturing the circuit board external connection bridging stack structure, the step of adopting a reflow soldering mode to dialyze the solder paste from the via hole and solder the solder paste with the via hole, so that the two ends of the FPC are soldered on the first bonding pad position and the second bonding pad position, wherein the reflow soldering comprises a preheating stage, a heat preservation stage, a reflow stage and a cooling stage, and the peak temperature of the reflow stage is 230-235 ℃; the reflow soldering time is 30-45s.
In the method for manufacturing the circuit board external connection bridging structure, the step of placing the solder paste on the first bonding pad position and the second bonding pad position by using steel screen printing comprises a pasty mixture formed by mixing soldering powder, soldering flux, a surfactant and a thixotropic agent.
The beneficial effects of the invention are as follows:
the manufacturing method of the external connection bridging stacking structure of the circuit board improves the design mode of the product, reduces the number of layers of the product and saves the cost; good circuit logic is achieved through the principle mode of external bridging; the overlap joint adopts external FPC's type, through SMT welded mode, improves the reliability of fixed bridging.
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments, as illustrated in the accompanying drawings.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a step flowchart of a circuit board external connection bridging stacking method in an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a circuit board stack in an embodiment of the invention;
FIG. 3 is a schematic diagram of the flow direction of solder paste according to an embodiment of the invention;
fig. 4 is a schematic view of the structure of the FPC in the embodiment of the present invention.
Reference numerals of the above drawings: 1-a PCB device side; 2-FPC; 3-a first bonding pad position; 4-a second pad site; 5-via holes; 6-tin paste; 20-a substrate layer; 21-copper foil layer.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Examples
As shown in fig. 1, a method for manufacturing an external connection bridging structure of a circuit board specifically includes the following steps:
acquiring a double-sided circuit PCB device surface 1, and determining a first bonding pad position 3 and a second bonding pad position 4 on the PCB device surface 1;
acquiring an FPC2, wherein the FPC2 comprises a substrate layer 20 and a copper foil layer 21, the copper foil layer 21 is attached to the substrate layer 20, two ends of the FPC2 are provided with through holes 5, and the through holes 5 penetrate through the substrate layer and the copper foil layer;
placing solder paste 6 on the first pad site 3 and the second pad site 4 using steel screen printing;
the first bonding pad 3 and the second bonding pad 4 are attached to the two ends of the FPC2 in an SMT (surface mount technology) attaching mode;
and (3) dialyzing the solder paste from the through hole by adopting a reflow soldering mode and soldering the solder paste with the through hole, so that two ends of the FPC are soldered on the first bonding pad position and the second bonding pad position.
By means of the method, the FPC2 is welded on the PCB device face 1 in an SMT welding mode in an external bridging mode, the product design mode is improved, the number of product layers is reduced, the manufacturing method of the circuit board external bridging stacking structure is achieved, cost is saved, and good circuit logic is achieved in an external bridging principle mode; the overlap joint adopts external FPC's type, through SMT welded mode, improves the reliability of fixed bridging.
Specifically, as shown in fig. 2, the FPC2 is disposed on the PCB device face 1, and the size of the FPC is 10% -45% of the size of the PCB device face 1. The FPC2 and the test pad on the PCB device surface 1 are arranged in a staggered mode.
FPC2 may be a single sided circuit, FPC2 including 25 sets of network logic.
Specifically, a plurality of bonding pads are arranged on the first bonding pad position 3 and the second bonding pad position 4, the bonding pad size is 0.35mm, and the line distance between the bonding pads is 0.15mm.
Specifically, the size of the via hole 5 is 0.1mm.
The FPC2 comprises two copper foil layers, wherein the two copper foil layers are respectively attached to two sides of the substrate, and a via hole penetrating through the substrate layer is connected between the two copper foil layers.
Specifically, the step of adopting a reflow soldering mode to enable solder paste to dialyze from the through hole and solder with the through hole, so that the reflow soldering in the process that the two ends of the FPC are soldered on the first bonding pad position and the second bonding pad position comprises a preheating stage, a heat preservation stage, a reflow stage and a cooling stage, and the peak temperature of the reflow stage is 230-235 ℃; the reflow soldering time is 30-45s.
The specific step of placing the solder paste on the first bonding pad position and the second bonding pad position by using steel screen printing comprises a paste mixture formed by mixing soldering tin powder, soldering flux, a surfactant and a thixotropic agent.
And (3) the SMT reflow soldering is carried out, so that the solder paste is melted into a molten state by heating, the through holes guide the solder paste to flow to the FPC, and after cooling, the solder paste and the metal through holes are soldered together.
The principles and embodiments of the present invention have been described in detail with reference to specific examples, which are provided to facilitate understanding of the method and core ideas of the present invention; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present invention, the present description should not be construed as limiting the present invention in view of the above.
Claims (10)
1. The manufacturing method of the circuit board external connection bridging structure is characterized by comprising the following steps:
acquiring a double-sided circuit PCB device surface, and determining a first bonding pad position and a second bonding pad position on the PCB device surface;
acquiring an FPC, wherein the FPC comprises a substrate layer and a copper foil layer, the copper foil layer is attached to the substrate layer, two ends of the FPC are provided with through holes, and the through holes penetrate through the substrate layer and the copper foil layer;
placing solder paste on the first bonding pad position and the second bonding pad position by using steel screen printing;
mounting the first bonding pad and the second bonding pad on two ends of the FPC in an SMT (surface mount technology) surface mount mode;
and (3) dialyzing the solder paste from the via hole and welding the solder paste with the via hole by adopting a reflow welding mode, so that two ends of the FPC are welded on the first bonding pad position and the second bonding pad position.
2. The method for manufacturing the circuit board external connection bridging structure according to claim 1, wherein the FPC is arranged on the surface of the PCB device, and the size of the FPC is 10% -45% of the size of the surface of the PCB device.
3. The method for manufacturing the circuit board external connection bridging stack structure according to claim 1, wherein the test pad on the surface of the FPC and the surface of the PCB device are arranged in a staggered manner.
4. The method for manufacturing the circuit board external connection bridging stack structure according to claim 1, wherein the FPC is a single-sided circuit and comprises 25 groups of network logic.
5. The method for manufacturing the circuit board external connection bridging stack structure according to claim 1, wherein a plurality of bonding pads are arranged on the first bonding pad position and the second bonding pad position, and the size of each bonding pad is 0.35mm.
6. The method for manufacturing the circuit board external connection bridging structure according to claim 5, wherein the line distance between the bonding pads is 0.15mm.
7. The method for manufacturing the circuit board external connection bridging structure according to claim 1, wherein the size of the through hole is 0.1mm.
8. The method for manufacturing the circuit board external connection bridging structure according to claim 1, wherein the FPC comprises two copper foil layers, the two copper foil layers are respectively attached to two sides of the base material, and a via hole penetrating through the base material layer is connected between the two copper foil layers.
9. The method for manufacturing the circuit board external connection bridging stack structure according to claim 1, wherein in the step of performing reflow soldering, the solder paste is dialyzed from the via hole and soldered with the via hole, so that the two ends of the FPC are soldered on the first pad position and the second pad position, the reflow soldering comprises a preheating stage, a heat preservation stage, a reflow stage and a cooling stage, and the peak temperature of the reflow stage is 230-235 ℃; the reflow soldering time is 30-45s.
10. The method of claim 1, wherein the solder paste includes a paste mixture of solder powder, flux, surfactant, and thixotropic agent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211729086.2A CN116709669A (en) | 2022-12-30 | 2022-12-30 | Manufacturing method of circuit board external connection bridging stacking structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211729086.2A CN116709669A (en) | 2022-12-30 | 2022-12-30 | Manufacturing method of circuit board external connection bridging stacking structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116709669A true CN116709669A (en) | 2023-09-05 |
Family
ID=87829977
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211729086.2A Pending CN116709669A (en) | 2022-12-30 | 2022-12-30 | Manufacturing method of circuit board external connection bridging stacking structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116709669A (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200944702Y (en) * | 2006-09-14 | 2007-09-05 | 华为技术有限公司 | Flexible printed circuit structure |
| US20140268594A1 (en) * | 2013-03-15 | 2014-09-18 | Sumitomo Electric Printed Circuits, Inc. | Method of embedding a pre-assembled unit including a device into a flexible printed circuit and corresponding assembly |
| CN105307420A (en) * | 2015-10-13 | 2016-02-03 | 惠州市蓝微电子有限公司 | PCB and FPC welding method and surface mounting jig |
| CN105338757A (en) * | 2015-12-04 | 2016-02-17 | 深圳威迈斯电源有限公司 | Printed circuit board manufacturing method and printed circuit board |
| CN107197600A (en) * | 2017-05-12 | 2017-09-22 | 深圳市路远电子科技有限公司 | The preparation method of printing circuit board element |
| WO2018099123A1 (en) * | 2016-12-01 | 2018-06-07 | 威创集团股份有限公司 | Printed circuit board and surface mount method |
| CN110958787A (en) * | 2020-01-07 | 2020-04-03 | 珠海元盛电子科技股份有限公司 | Welding method for multilayer interconnection FPC preset solder paste |
| CN113270383A (en) * | 2021-05-13 | 2021-08-17 | 深圳市汇顶科技股份有限公司 | Chip assembly and manufacturing method thereof |
| CN113438807A (en) * | 2021-06-30 | 2021-09-24 | 东莞市小精灵教育软件有限公司 | Connecting structure of soft board and hard board and manufacturing method thereof |
| CN114603225A (en) * | 2022-02-10 | 2022-06-10 | 福莱盈电子股份有限公司 | Tin soldering process for increasing preformed tin blocks |
-
2022
- 2022-12-30 CN CN202211729086.2A patent/CN116709669A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200944702Y (en) * | 2006-09-14 | 2007-09-05 | 华为技术有限公司 | Flexible printed circuit structure |
| US20140268594A1 (en) * | 2013-03-15 | 2014-09-18 | Sumitomo Electric Printed Circuits, Inc. | Method of embedding a pre-assembled unit including a device into a flexible printed circuit and corresponding assembly |
| CN105307420A (en) * | 2015-10-13 | 2016-02-03 | 惠州市蓝微电子有限公司 | PCB and FPC welding method and surface mounting jig |
| CN105338757A (en) * | 2015-12-04 | 2016-02-17 | 深圳威迈斯电源有限公司 | Printed circuit board manufacturing method and printed circuit board |
| WO2018099123A1 (en) * | 2016-12-01 | 2018-06-07 | 威创集团股份有限公司 | Printed circuit board and surface mount method |
| CN107197600A (en) * | 2017-05-12 | 2017-09-22 | 深圳市路远电子科技有限公司 | The preparation method of printing circuit board element |
| CN110958787A (en) * | 2020-01-07 | 2020-04-03 | 珠海元盛电子科技股份有限公司 | Welding method for multilayer interconnection FPC preset solder paste |
| CN113270383A (en) * | 2021-05-13 | 2021-08-17 | 深圳市汇顶科技股份有限公司 | Chip assembly and manufacturing method thereof |
| CN113438807A (en) * | 2021-06-30 | 2021-09-24 | 东莞市小精灵教育软件有限公司 | Connecting structure of soft board and hard board and manufacturing method thereof |
| CN114603225A (en) * | 2022-02-10 | 2022-06-10 | 福莱盈电子股份有限公司 | Tin soldering process for increasing preformed tin blocks |
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