CN115643697A - Production process of multilayer flexible circuit board - Google Patents
Production process of multilayer flexible circuit board Download PDFInfo
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- CN115643697A CN115643697A CN202211247091.XA CN202211247091A CN115643697A CN 115643697 A CN115643697 A CN 115643697A CN 202211247091 A CN202211247091 A CN 202211247091A CN 115643697 A CN115643697 A CN 115643697A
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Abstract
The invention provides a production process of a multilayer flexible circuit board, and relates to the technical field of flexible circuit board production, wherein S1 and design are carried out, S2 and recheck are carried out, S3 and cutting are carried out, S4 and cleaning are carried out, S5 and laminating are carried out, S6 and annealing treatment are carried out, S7 and punching are carried out, S8 and stripping are carried out, S9 and processing forming are carried out, and S10 and inspection are carried out. Heating a compression plate to 260-300 ℃, and preserving heat; after heat preservation is carried out for 1h, the compression plate is removed, and then the compression plate is placed in the environment of room temperature for cooling; heating the cooled compression plate to 1000 ℃ for the second time under the standard atmospheric pressure, and preserving the heat for 30-45S; the compression plate after heat preservation is taken out to distilled water, and the compression plate is cooled by a water washing mode, so that the residual stress of copper can be reduced by annealing treatment, the size is stabilized, the deformation and crack tendency is reduced, the compression plate can be softer when being used, and the flexible plate can not be used due to the property of copper when being frequently changed.
Description
Technical Field
The invention relates to the technical field of flexible circuit board production, in particular to a production process of a multilayer flexible circuit board.
Background
A Flexible Printed Circuit Board (FPC), which is commonly known in the industry, is a Printed Circuit Board made of a Flexible insulating base material (mainly polyimide or polyester film), and has many advantages that a rigid Printed Circuit Board does not have. For example, it can be freely bent, rolled, folded. The FPC can greatly reduce the volume of electronic products, and is suitable for the development of the electronic products in the directions of high density, miniaturization and high reliability. Therefore, the FPC is widely applied to the fields or products of aerospace, military, mobile communication, laptop, computer peripheral equipment, PDA, digital camera and the like, and has the advantages of good heat dissipation and weldability, easy assembly and connection, low comprehensive cost and the like.
The flexible printed circuit board has a single-sided surface, a double-sided surface and a multi-layer board. The adopted base material is mainly a polyimide copper clad laminate. The material has high heat resistance and good dimensional stability, and is pressed with a covering film with mechanical protection and good electrical insulation performance to form a final product. The surface layer and the inner layer conductor of the double-sided and multi-layer printed circuit board are electrically connected with the inner and outer layer circuits through metallization.
The flexible Circuit board has four functions, which are a Lead Line (Lead Line), a Printed Circuit (Printed Circuit), a Connector (Connector), and an Integration of functions, and the applications cover the range of computers, computer peripheral systems, consumer electronic devices, automobiles, and the like.
However, in the prior art, the existing flexible circuit board production process can meet the situation of circuit board usage of general requirements, but under the condition that the shape is frequently changed, such as a circuit board used in a folding mobile phone or a circuit board used in a notebook computer, when the circuit board is used, the shape of the circuit board needs to be frequently changed, the probability of damage is much higher than that of the circuit board used in a normal static state, and the circuit board used is much softer, such as the application number: 2016109965.5, entitled "a method for manufacturing a multilayer flexible circuit board" is disclosed, which does not require the corrosion of copper, avoids the waste of materials, prevents the generation of a large amount of toxic corrosive liquid, and reduces the environmental pollution. When the double-sided board is prepared, the through holes and the circuits are prepared in one flow, so that the consistency of the electrical properties of the wires in the through holes and the wires on the surface of the board is ensured, the process complexity is greatly reduced, and the integral manufacturing cost is reduced. The invention simplifies the production process, saves the production cost, improves the processing efficiency, can provide guarantee for subsequent high-precision images, has no problem in normal use and longer service life, but the copper foil is deformed for a long time when the shape of the multilayer linear flexible plate needs to be changed frequently, so that the copper foil is damaged, and the probability of damage is higher.
Disclosure of Invention
The invention aims to solve the defects in the prior art, the form of the cable needs to be changed frequently, and the probability of damage is high.
In order to achieve the purpose, the invention adopts the following technical scheme: the production process of the multilayer flexible circuit board comprises the following steps:
s1, designing: designing a required circuit board according to a current-carrying capacity principle;
s2, rechecking: loading a designed circuit board in design software, and testing whether the design requirement is met or not through software simulation;
s3, cutting: selecting proper copper foil, setting the double-layer coil materials into corresponding sizes according to design requirements by using a shearing machine, automatically cutting the double-layer coil materials into corresponding quantities according to the designed layer number;
s4, cleaning: cleaning the copper foil cut in the step S3, and then drying;
s5, laminating: coating a single surface of the dried copper foil, filling the middle of two surfaces without coating with a metal solution with good conductivity to form a compression plate, and removing the coating;
s6, annealing treatment: annealing the compression plate;
s7, punching: drilling the annealed compression plate by using a laser drill mode, and electroplating inert metal in the hole after drilling;
s8, removing the film: after punching, etching is carried out, and the method specifically comprises the following steps: developing, etching, pattern electroplating, film stripping, micro-etching, acid washing, oxidation resistance and drying;
s9, processing and forming: the specific process is as follows: chemical cleaning, covering film appearance, pressing, baking and silk-screen printing;
and S10, checking.
As a preferred embodiment, the specific operation steps of step S2 are:
s2.1, copying the designed data into software;
s2.2, comparing the data of the software test with the designed numerical value;
and S2.3, producing when the difference between the test result and the value reaches the same threshold value, otherwise, adjusting until the value obtained by the software and the designed value are in the range of the threshold value, wherein the test result is passed, and finally producing.
Adopt above-mentioned technical scheme: production is being carried out after the contrast, prevents to produce after, and the product can not reach expected value, influences the precision of producing the product.
As a preferred embodiment, the specific operation steps of step S4 are as follows:
s4.1, removing the protective oil film on the surface of the copper foil from the cut copper foil;
s4.2, polishing the copper foil with the oil film removed by using a polishing machine, and simultaneously polishing to enable the thickness of the copper foil to reach the designed threshold range;
s4.3, cleaning the polished copper foil with distilled water, cleaning scraps on the surface of the copper foil, and then drying;
and S4.4, transferring the dried copper foil to the next procedure in a dust-free environment.
Adopt above-mentioned technical scheme: the surface of the copper foil is cleaned, impurities on the surface of the copper foil are removed, and the impurities can be prevented from reducing the product quality.
As a preferred embodiment, the specific operation steps of step S5 are as follows;
s5.1, plating a film on one side of the copper foil in a dust-free environment, wherein the plated film can be removed by using distilled water;
s5.2, adhering the two non-coated surfaces of the copper foils together, filling the non-coated surfaces with a metal solution with good conductivity to adhere the two copper foils together, and standing and cooling the copper foils for use;
s5.3, removing excessive metal solution fixing products between the two copper foils to form a metal plate;
and S5.4, pressing the metal plate in a hot pressing mode to enable the metal plate to be subjected to secondary fixed forming to form the compression plate.
As a preferred implementation mode, production is carried out after fixing, and the two copper foils are prevented from shifting in position when being processed, so that the specifications of the two copper foils are different, and the products produced together have insufficient yield.
As a preferred embodiment, the specific operation steps of step S6 are as follows:
s6.1, heating the compression plate to 260-300 ℃, and preserving heat;
s6.2, removing the compression plate after heat preservation is carried out for 1h, and then cooling the compression plate in a room-temperature environment;
s6.3, heating the cooled compression plate to 1000 ℃ for the second time under the standard atmospheric pressure, and preserving the heat for 30-45S;
and S6.4, taking out the compression plate after heat preservation into distilled water, and cooling the compression plate by using a water washing mode.
As a preferred embodiment, the annealing process reduces the residual stress of the copper, stabilizes the dimensions, reduces the tendency to deform and crack, makes it more flexible when used, and does not cause the flexible sheet to be used due to the inherent properties of copper when it is constantly changing its form.
As a preferable embodiment, in the step of removing the plating film in step S5, the plating film may be removed by washing with distilled water, and then performing a drying process.
As a preferred embodiment, the steps S8 and S9 may be performed in a conventional manner.
As a preferred embodiment, the specific steps of the detection in step S10 are as follows:
s10.1, detecting the manufactured circuit board, determining that the circuit board is good when the tested value and the designed value reach a certain threshold value, and entering the next detection step, wherein the circuit board is unqualified when the tested value and the designed value do not reach the certain threshold value;
and S10.2, bending the manufactured product back and forth for a certain number of times, testing, and checking whether the product after repeated folding can meet the threshold value of a design numerical value.
Compared with the prior art, the invention has the advantages and positive effects that,
1. in the invention, the compression plate is heated to 260-300 ℃ for heat preservation; after heat preservation is carried out for 1h, the compression plate is removed, and then the compression plate is placed in the environment of room temperature for cooling; heating the cooled compression plate to 1000 ℃ for the second time under the standard atmospheric pressure, and preserving the heat for 30-45S; the compression plate after heat preservation is taken out to distilled water, and the compression plate is cooled by using a water washing mode, so that the residual stress of copper can be reduced by annealing treatment, the size is stabilized, the deformation and crack tendency is reduced, the compression plate can be softer when being used, and the flexible plate can not be used due to the property of copper when the shape of the compression plate is changed frequently.
2. In the invention, the protective oil film on the surface of the copper foil is removed from the cut copper foil; polishing the copper foil with the oil film removed by using a polishing machine, and simultaneously polishing to enable the thickness of the copper foil to reach the designed threshold range; cleaning the polished copper foil with distilled water, cleaning scraps on the surface of the copper foil, and drying; the dried copper foil is transferred to the next procedure in a dust-free environment, the surface of the copper foil is cleaned, impurities on the surface of the copper foil are removed, and the situation that the impurities bring reduction of the product excellence can be prevented.
3. In the invention, the designed data is copied into the software; comparing the data of the software test with the designed numerical value; the difference between the test result and the numerical value reaches the same threshold value, production can be carried out, otherwise, adjustment is carried out until the numerical value obtained by software and the designed numerical value are in the range of the threshold value, the test result is passed, production is carried out finally, production is carried out after comparison, and after production is prevented, the product cannot reach the expected value, and the precision of the produced product is influenced.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.
Example 1
The invention provides a technical scheme that: the production process of the multilayer flexible circuit board comprises the following steps:
s1, designing: designing a required circuit board according to a current-carrying capacity principle;
s2, rechecking: loading a designed circuit board in design software, and testing whether the design requirement is met or not through software simulation;
s2.1, copying the designed data into software;
s2.2, comparing the data of the software test with the designed numerical value;
s2.3, production can be carried out when the difference between the test result and the numerical value reaches the same threshold value, otherwise, adjustment is carried out until the numerical value obtained by the software and the designed numerical value are within the range of the threshold value, the test result is passed, production is carried out finally, production is carried out after comparison, and the problem that after production, the product cannot reach the expected value and the precision of the produced product is influenced is prevented;
s3, cutting: selecting proper copper foil, setting the double-layer coil materials into corresponding sizes according to design requirements by using a shearing machine, automatically cutting the double-layer coil materials into corresponding quantities according to the designed layer number;
s4, cleaning: cleaning the copper foil cut in the step S3, and then drying;
s4.1, removing the protective oil film on the surface of the copper foil from the cut copper foil;
s4.2, polishing the copper foil with the oil film removed by using a polishing machine, and simultaneously polishing to enable the thickness of the copper foil to reach the designed threshold range;
s4.3, cleaning the polished copper foil with distilled water, cleaning scraps on the surface of the copper foil, and then drying;
s4.4, transferring the dried copper foil to the next procedure in a dust-free environment;
the surface of the copper foil is cleaned, and impurities on the surface of the copper foil are removed, so that the reduction of the product excellence caused by the impurities can be prevented.
S5, laminating: carrying out single-side coating on the dried copper foil, filling the middle of two surfaces without coating with a metal solution with good conductivity to form a compression plate, removing the coating, cleaning with distilled water to remove the coating, and then carrying out drying treatment;
s5.1, plating a film on one side of the copper foil in a dust-free environment, wherein the plated film can be removed by using distilled water;
s5.2, adhering the uncoated surfaces of the two copper foils together, filling the two copper foils with a metal solution with good conductivity to adhere the two copper foils together, and standing and cooling the two copper foils for use;
s5.3, removing excessive metal solution fixing products between the two copper foils to form a metal plate;
s5.4, pressing the metal plate in a hot pressing mode to enable the metal plate to be fixed and formed for the second time to form a compression plate;
s6, annealing treatment: annealing the compression plate;
s6.1, heating the compression plate to 260-300 ℃, and preserving heat;
s6.2, removing the compression plate after heat preservation is carried out for 1h, and then cooling the compression plate in a room-temperature environment;
s6.3, heating the cooled compression plate to 1000 ℃ for the second time under the standard atmospheric pressure, and preserving the heat for 30-45S;
s6.4, taking out the compression plate after heat preservation into distilled water, and cooling the compression plate in a water washing mode;
the annealing treatment can reduce the residual stress of copper, stabilize the size, reduce the deformation and crack tendency, ensure that the flexible printed circuit board can be softer when in use, and can not cause the flexible printed circuit board to be used due to the property of the copper when the shape of the flexible printed circuit board is frequently changed.
S7, punching: drilling the annealed compression plate by using a laser drill mode, and electroplating inert metal inside the hole after drilling the hole;
s8, removing the film: after punching, etching is carried out, and the method specifically comprises the following steps: developing, etching, pattern electroplating, film stripping, microetching, acid washing, antioxidation and drying by adopting a conventional mode;
s9, processing and forming: the specific process is as follows: chemical cleaning, covering film appearance, pressing, baking and silk-screen printing by adopting a conventional mode;
and S10, checking.
S10.1, detecting the manufactured circuit board, determining that the circuit board is good when the tested value and the designed value reach a certain threshold value, and entering the next detection step, wherein the circuit board is unqualified when the tested value and the designed value do not reach the certain threshold value;
and S10.2, bending the manufactured product back and forth for a certain number of times, testing, and checking whether the product after repeated folding can meet the threshold of a design numerical value.
Comparative example 1
This example is substantially the same as the method of example 1 provided, with the main differences being: the operation step of step S6 is not performed;
comparative example 2
This example is substantially the same as the method of example 1 provided, with the main differences being: the operation step of step S4 is not performed.
Comparative example 3
This example is substantially the same as the method of example 1 provided, with the main differences being: the operation step of step S2 is not performed.
Performance testing
The softness of the product, the excellence of the product and the precision of the product of the production process of the multilayer flexible wiring board provided in example 1 and comparative examples 1 to 3 were taken in equal amounts, respectively:
| flexibility of the film | Excellence in | Accuracy of | |
| Example 1 | 99.9％ | 99.9％ | 99.9％ |
| Comparative example 1 | 76.8％ | 99.9％ | 99.9％ |
| Comparative example 2 | 99.9％ | 95.5％ | 99.9％ |
| Comparative example 3 | 99.9％ | 99.9％ | 95.5 |
By analyzing the relevant data in the tables, the design of the invention is as follows:
heating the compression plate to 260-300 ℃, and preserving heat; after heat preservation is carried out for 1h, the compression plate is removed, and then the compression plate is placed in the environment of room temperature for cooling; heating the cooled compression plate to 1000 ℃ for the second time under the standard atmospheric pressure, and preserving the heat for 30-45 seconds; the compression plate after heat preservation is taken out to distilled water, the compression plate is cooled by a water washing mode, the residual stress of copper can be reduced by annealing treatment, the size is stabilized, the deformation and crack tendency is reduced, the compression plate can be softer when in use, and the flexible plate can not be used due to the property of copper when the shape of the compression plate is changed frequently;
removing the protective oil film on the surface of the copper foil from the cut copper foil; polishing the copper foil with the oil film removed by using a polishing machine, and simultaneously polishing to enable the thickness of the copper foil to reach the designed threshold range; cleaning the polished copper foil with distilled water, cleaning scraps on the surface of the copper foil, and drying; the dried copper foil is transferred to the next procedure in a dust-free environment, the surface of the copper foil is cleaned, impurities on the surface of the copper foil are removed, and the reduction of the product quality caused by the impurities can be prevented;
copying the designed data into software; comparing the data of the software test with the designed numerical value; the difference between the test result and the value reaches the same threshold value, production can be carried out, otherwise, adjustment is carried out until the value obtained by the software and the designed value are in the range of the threshold value, the test result is passed, production is carried out finally, production is carried out after comparison, and after production is prevented, the product cannot reach the expected value, and the precision of the produced product is influenced.
The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.
Claims (8)
1. The production process of the multilayer flexible circuit board is characterized by comprising the following steps:
s1, designing: designing a required circuit board according to a current-carrying capacity principle;
s2, rechecking: loading a designed circuit board in design software, and testing whether the design requirement is met or not through software simulation;
s3, cutting: selecting proper copper foil, setting the double-layer coil material into a corresponding size according to design requirements by using a shearing machine, automatically cutting, and cutting into corresponding quantity according to the designed layer number;
s4, cleaning: cleaning the copper foil cut in the step S3, and then drying;
s5, laminating: coating a single surface of the dried copper foil, filling the middle of two surfaces without coating with a metal solution with good conductivity to form a compression plate, and removing the coating;
s6, annealing treatment: annealing the compression plate;
s7, punching: drilling the annealed compression plate by using a laser drill mode, and electroplating inert metal inside the hole after drilling the hole;
s8, removing the film: after punching, etching is carried out, and the method specifically comprises the following steps: developing, etching, pattern electroplating, film stripping, micro-etching, acid washing, oxidation resistance and drying;
s9, processing and forming: the specific process is as follows: chemical cleaning, covering the film appearance, pressing, baking and silk-screen printing;
and S10, checking.
2. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the specific operation steps of the step S2 are as follows:
s2.1, copying the designed data into software;
s2.2, comparing the data of the software test with the designed numerical value;
and S2.3, producing when the difference between the test result and the numerical value reaches the same threshold value, otherwise, adjusting until the numerical value obtained by the software and the designed numerical value are in the range of the threshold value, wherein the test result is passed, and finally producing.
3. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the specific operation steps of the step S4 are as follows:
s4.1, removing the protective oil film on the surface of the copper foil from the cut copper foil;
s4.2, polishing the copper foil with the oil film removed by using a polishing machine, and simultaneously polishing to enable the thickness of the copper foil to reach the designed threshold range;
s4.3, cleaning the polished copper foil with distilled water, cleaning scraps on the surface of the copper foil, and then drying;
and S4.4, transferring the dried copper foil to the next working procedure in a dust-free environment.
4. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the specific operation steps of the step S5 are as follows;
s5.1, plating a film on one side of the copper foil in a dust-free environment, wherein the plated film can be removed by using distilled water;
s5.2, adhering the two non-coated surfaces of the copper foils together, filling the non-coated surfaces with a metal solution with good conductivity to adhere the two copper foils together, and standing and cooling the copper foils for use;
s5.3, removing excessive metal solution fixing products between the two copper foils to form a metal plate;
and S5.4, pressing the metal plate in a hot pressing mode to enable the metal plate to be fixed and formed for the second time to form the compression plate.
5. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the specific operation steps of the step S6 are as follows:
s6.1, heating the compression plate to 260-300 ℃, and preserving heat;
s6.2, removing the compression plate after heat preservation for 1h, and then placing the compression plate in a room-temperature environment for cooling;
s6.3, secondarily heating the cooled compression plate to 1000 ℃ under the standard atmospheric pressure, and preserving heat for 30-45S;
and S6.4, taking the compression plate after heat preservation out into distilled water, and cooling the compression plate by using a water washing mode.
6. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: in the step S5, the coating is removed by washing with distilled water, and then drying is performed.
7. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the steps S8 and S9 may be performed in a conventional manner.
8. The process for producing a multilayer flexible wiring board according to claim 1, characterized in that: the specific steps of the detection in the step S10 are as follows:
s10.1, detecting the manufactured circuit board, determining that the manufactured circuit board is a good product when the tested value and the designed value reach a certain threshold value, and entering the next detection step, wherein the manufactured circuit board is an unqualified product when the tested value and the designed value do not reach the certain threshold value;
and S10.2, bending the manufactured product back and forth for a certain number of times, testing, and checking whether the product after repeated folding can meet the threshold value of a design numerical value.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117202515A (en) * | 2023-11-07 | 2023-12-08 | 深圳市中电联科技有限公司 | Automatic punching control method and system for flexible circuit board |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117202515A (en) * | 2023-11-07 | 2023-12-08 | 深圳市中电联科技有限公司 | Automatic punching control method and system for flexible circuit board |
| CN117202515B (en) * | 2023-11-07 | 2024-01-19 | 深圳市中电联科技有限公司 | Automatic punching control method and system for flexible circuit board |
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