KR101241070B1 - The printed circuit board manufacturing method - Google Patents

Abstract

PURPOSE: A flexible printed circuit board manufacturing method is provided to prevent the generation of a stepped pulley in an exposing operation by blanking a subsidiary material according to a part which needs to be bent and mounting before the exposure operation. CONSTITUTION: A hole is processed on a substrate for forming a PTH(S10). A conductive film is formed by a chemical copper process on the substrate(S20). A dry film and release paper are coated on both sides of the substrate(S30). A subsidiary material is blanked on the substrate(S40). The blanked subsidiary material is mounted on an exposure film(S50). A circuit is formed by irradiating UV to the exposure film(S60). A dry film and release paper positioned nearby the PTH are developed(70). A copper coating process is performed in an upper part of the conductive film(S80). The dry film and the release paper positioned on both sides of the substrate are delaminated(S90). [Reference numerals] (AA) Start; (BB) End; (S10) First process for processing a PTH; (S20) Second process for a chemical copper process; (S30) Third process for coating a dry film and release paper; (S40) Fourth process for blanking a subsidiary material; (S50) Fifth process for mounting the blanked subsidiary material on an exposure film; (S60) Sixth process for exposure; (S70) Seventh process for developing the dry film and release paper; (S80) Eighth process for planting; (S90) Ninth process for delaminating the dry film and release paper

Description

The printed circuit board manufacturing method

The present invention relates to a flexible printed circuit board manufacturing method, and more particularly, it is possible to overcome the stepped gap by attaching the punched sub-material to the stepped portion generated to overcome the step generated during the exposure operation on both sides of the flexible printed circuit board. The present invention relates to a flexible printed circuit board manufacturing method.

With the rapid growth of current electronic components, component embedding technology has also developed, requiring a highly flexible and flexible flexible multilayer printed circuit board to be easily embedded in complex and narrow spaces.

A typical flexible printed circuit is a circuit board in which a complex circuit is formed on a flexible insulating film. A flexible printed circuit is a substrate using a heat-resistant plastic film such as polyester (polyester) or polyimide (pi). It is easy to use flexible printed circuit boards, but it is easy to use multilayer flexible printed circuit boards to build high functionality. Therefore, in order to secure flexibility in multilayer flexible printed circuit boards, the area requiring flexibility is different from other areas. And the flexibility to minimize the coverlay (Coverlay) or PSR (Photo Solder Resist) to secure the flexibility, but the step is generated due to the step with the other area is a defect occurs during the progress of the pattern.

FIG. 1 is a process diagram showing a flow of a conventional method for manufacturing a flexible printed circuit, and FIG. 2 is a view showing a phenomenon generated by a conventional method for manufacturing a flexible printed circuit board.

In the conventional method of manufacturing a flexible printed circuit, a step with other areas is minimized as the layer and coverlay or PSR (Photo Solder Resist) are minimized unlike other areas in order to secure flexibility in areas requiring flexibility. Due to the generated step, bending occurs in the bending area during the exposure operation, thereby causing a problem in that the proper exposure operation is not performed.

Korea Patent Office Registered Patent Publication No. 10-1009729

The present invention is to solve the conventional problems as described above, the object of the present invention is to provide a flexible printing to prevent the step is generated even during the exposure operation by punching and attaching the sub-materials according to the bending portion before the exposure operation It is to provide a circuit board manufacturing method.

In order to achieve the above object, the present invention is implemented by the following embodiments.

The present invention relates to a first process (S10) of processing a hole with an ultraviolet laser drill or a CNC drill in order to form PTH on a sheet of double-sided flexible copper-clad laminate, and to a hole formed in the sheet of double-sided flexible copper-clad laminate. In order to impart electroconductivity, the second step (S20) of electroless chemical copper, the third step (S30) of coating dry film and release paper on both sides of the sheet of double-sided flexible copper-clad laminate, and the third step (S30) The fourth step (S40) for punching the subsidiary materials to be attached to the portion requiring flexibility before the exposure operation on the finished substrate, the fifth step (S50) for attaching the subsidiary materials punched in the fourth step (S40) to the exposure film In the third step (S60), the dry film coated in the third step (S30) and the exposure film attached to the subsidiary material is placed on one surface of the release paper, the fifth step (S60) for attaching the punched subsidiary material to form a circuit by irradiating UV And the sixth step In step S60, an etching solution is added to the uncured dry film and the release paper to develop the dry film and the release paper located around the PTH, and the substrate from which the dry film is removed in the seventh step (S70). Eighth step (S80) for plating on top of the, and the ninth step (S90) for peeling the dry film and the release paper located on both sides of the substrate passed through the eighth step (S80).

The subsidiary material punched out in the fourth step S40 of punching the subsidiary material is characterized in that it uses a PI series or a PET series.

As described above, the method of manufacturing a flexible printed circuit board according to the present invention minimizes the layer and coverlay or PSR (Photo Solder Resist), thereby attaching subsidiary materials to the bent portion, and then exposing work, thereby providing flexibility. It is effective to prevent the occurrence of bending due to the step generated between the required portion and the other portion.

In addition, the present invention has a problem that the productivity is reduced and the additional process occurs by reprocessing the defects caused by the step of the bent area after the reprocessing, but the additional step is not necessary because it can overcome the step, productivity improvement and cost reduction The effect to do it can be planned.

1 is a schematic flowchart of a method of manufacturing a conventional flexible printed circuit board;
2 is a view showing a phenomenon caused by a conventional method for manufacturing a flexible printed circuit board.
3 is a flowchart illustrating a method of manufacturing a flexible printed circuit board according to an embodiment of the present invention.
4 is a view illustrating a state in which a subsidiary material is attached to a stepped portion by a method of manufacturing a flexible printed circuit board according to an exemplary embodiment of the present invention.

Hereinafter, a method of manufacturing a flexible printed circuit board according to the present invention will be described in detail with reference to the accompanying drawings. It is to be noted that like elements in the drawings are represented by the same reference numerals as possible. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

3 is a flowchart illustrating a method of manufacturing a flexible printed circuit board according to an embodiment of the present invention, and FIG. 4 is a subsidiary material attached to a stepped portion by a method of manufacturing a flexible printed circuit board according to an embodiment of the present invention. It is a figure which shows the state.

In one embodiment of the present invention, a flexible printed circuit board manufacturing method includes a first process (S10) of processing a hole by using an ultraviolet laser drill or a CNC drill to form PTH on a single-sided flexible copper clad laminate. A second step (S20) of performing electroless chemical copper in order to impart conductivity to a hole formed in the double-sided flexible copper-clad laminate, and a third process of coating a dry film and a release paper on both sides of the single-sided flexible copper-clad laminate ( S30), the fourth step (S40) for punching the subsidiary materials to be attached to the portion requiring flexibility before performing the exposure operation to the substrate finished up to the third step (S30), the auxiliary materials punched out in the fourth step (S40) A sixth process of forming a circuit by irradiating UV with UV light on a surface of a dry film coated in the third process (S50), the third process (S30), and a release paper on which a subsidiary material is mounted; S60), and the sixth In step S60, an etching solution is added to the uncured dry film and the release paper to develop the dry film and the release paper located in the vicinity of the PTH, and the dry film is removed in the seventh step (S70). Eighth step (S80) for plating the upper portion of the substrate, and a ninth step (S90) for peeling the dry film and the release paper located on both sides of the substrate passed through the eighth step (S80).

The first step (S10) is a process for processing PTH on a printed circuit board, a general printed circuit board is formed by laminating copper foil on both sides of the insulating film. In the first step S10, in order to process the PTH, minute pores, or holes, penetrating between both surfaces (surface and back surface) (one surface and the opposite surface) of the substrate E are processed. Many holes are formed in one printed board E. FIG. Further, the hole is used for conducting connection between circuit patterns A on both sides, and / or for attaching a semiconductor component mounted on the circuit pattern A and the like. As for the hole diameter of a hole, the thing of 0.2 mm or more and 0.5 mm or less is increasing, and the thing of about 0.1 mm by the drill method and the thing of about 0.05 mm are appeared by the laser method.

The second step (S20) is a chemical copper treatment process, and a conductive coating is formed by performing a chemical copper treatment on the substrate E having a hole processed therein. The chemical copper treatment refers to an electroless copper plating process, also referred to as chemical or catalytic plating. The inner wall of the hole is coated with copper, which is a conductor, to impart conductivity, and the thickness of copper to be plated is 0.3 to 1.0 μm, and Pd is mainly used. In the second step (S20) of the present invention, a direct plating process may be performed instead of the chemical copper treatment.

The third step (S30) is a process of coating a dry film and a release paper. Dry film and release paper are pressed on both sides of the substrate E to be adhered to the substrate E by applying a predetermined heat and pressure.

The fourth step (S40) is a step of punching the subsidiary materials to be attached to the portion requiring flexibility before performing the exposure operation on the substrate after the third step (S30), wherein the subsidiary materials are formed of PI series or PET series.

An adhesive layer and a release paper are formed on both sides of the subsidiary material so that the release paper on one side is removed, and then the subsidiary material is attached to one side of the substrate and laminated. Laminated subsidiary materials will be punched out as the shape of the step is generated. The punching method at this time uses a mold punching and a wooden punching, and during the punching process, the auxiliary material shape does not have to be more precise than the outer shape. It is preferable.

The fifth step (S50) is a step of attaching the subsidiary material punched out in the fourth step (S40) to the exposure film, the subsidiary material is completed in the process of punching the subsidiary material to remove the release paper of the other side on the exposure film In the case of attachment, it is also possible to use a mold (JIG) which is manually attached or manufactured in the form of attachment.

The sixth step (S60) is a step of exposing only one surface of the dry film and the release paper coated substrate (E), the exposure film in the state in which the auxiliary material is mounted on the dry film and the release paper to match the light energy during the exposure time To provide the necessary pattern images.

In the seventh step S70, when the dry film and the release paper exposed in the sixth step are left uncured, the dry film and the release paper are removed using a developer to remove the uncured dry film and the release paper.

The eighth step (S80) is a step of copper plating the PTH, so that the copper plating can be formed on the conductive film. Electroplating is a process of secondary plating the copper of the thickness specified in the pattern and the inner wall of the hole by using the electroprecipitation method. The amount of precipitation is determined by the current density and the precipitation time.

The ninth step (S90) is a step of peeling the dry film and the release paper located on both sides of the flexible copper-clad laminate. By peeling and removing the dry film and the release paper as described above to facilitate the formation of a fine circuit on the surface of the dynamic layer plate.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Should be interpreted as falling within the scope of.

S10: First process for processing holes
S20: second process for electroless chemical copper
S30: third process of coating dry film and release paper
S40: 4th process for punching subsidiary materials
S50: fifth process of attaching the punched subsidiary material to the exposure film
S60: 6th process to expose
S70: 7th process for developing dry film and release paper
S80: 8th process of plating
S90: 9th process of peeling dry film and release paper

Claims (2)

In the first step (S10) of processing a hole with an ultraviolet laser drill or a CNC drill in order to form PTH on a sheet of double-sided flexible copper-clad laminate, conductivity is provided to a hole formed in the sheet of double-sided flexible copper-clad laminate. In order to finish the second step (S20) of electroless chemical copper, the third step (S30), the third step (S30) of coating the dry film and the release paper on both sides of the sheet of double-sided flexible copper clad laminate, 4th step S40 of punching an auxiliary material to be attached to the part which needs bendability before an exposure operation | work, 5th process S50 of attaching the auxiliary material punched in the said 4th process S40 to an exposure film, said said 5th process The sixth step (S60) and the sixth step (S60) and the sixth step (S60) to form a circuit by irradiating UV and put the exposure film attached to the subsidiary material on one surface of the dry film and the release paper coated in the third step (S30) Dry film and release paper The seventh step (S70) of developing the dry film and release paper located in the periphery of the PTH by adding the quenching solution, and the eighth step (S80) of plating on the substrate on which the dry film is removed in the seventh step (S70) And a ninth step (S90) of peeling off the dry film and the release paper located on both sides of the substrate which have passed through the eighth step (S80). The method of claim 1,
The subsidiary material punched out in the fourth step (S40) for punching the subsidiary material is a flexible printed circuit board manufacturing method, characterized in that using the PI series or PET series.

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