KR20100081811A - Method of manufacturing a printed circuit board with a gravure printing - Google Patents

Abstract

PURPOSE: A manufacturing method of a printed circuit board is provided to reduce manufacturing costs and time by forming a circuit layer using a gravure printing method through a base substrate which has a via passing through an insulating layer. CONSTITUTION: A base substrate including a via passing through an insulating layer is provided. A conductive bump is printed in the upper part of a lower metal foil(110). An insulating layer is laminated in the upper part of the lower metal foil so that a bump is projected. An upper metal foil(170) is laminated in the upper part of the insulating layer in order to form a via by pressing the protrusion of the bump. The upper end surface and lower end surface are exposed by removing the lower part metal foil and the upper part metal foil. A circuit layer is formed with a gravure printing method. The circuit layer comprises a circuit pattern which electrically connects an upper side to a lower side of an insulating layer(150) with a via.

Description

Manufacturing method of printed circuit board using gravure printing {METHOD OF MANUFACTURING A PRINTED CIRCUIT BOARD WITH A GRAVURE PRINTING}

The present invention relates to a method of manufacturing a printed circuit board.

Printed Circuit Board (PCB) plays a role of mechanically fixing the components at the same time by electrically connecting the components mounted through the wiring pattern formed on the insulating material such as phenolic resin insulation board or epoxy resin insulation board and supplying power. The printed circuit board includes a single-sided PCB in which wiring is formed only on one side of an insulating board, a double-sided PCB in which wiring is formed on both sides, and a multi-layered multi-layered board (MLB).

As a method of forming a wiring pattern on a printed circuit board (PCB), an additive process, a subtractive process, a modified semi additive process (MSAP), and a semi additive process (SAP) are formed. ) Is used.

1 is a diagram illustrating a process of forming a via and a wiring pattern by the SAP method according to the prior art in the process order.

First, as shown in FIG. 1A, an insulating material 1 on which the wiring pattern 15 (see FIG. 1F) is to be formed is stacked on the copper foil 3, and a via hole 5 exposing the copper foil 3 to the insulating material is formed. do. Thereafter, as shown in FIG. 1B, the seed layer 7 is formed. The formation of the seed layer 7 is a pretreatment process for the electroplating process to be performed later. Next, as shown in FIG. 1C, the plating resist layer 9 is formed at portions except the portions where the wiring patterns 15 and the vias 11 (see FIG. 1F) are to be formed. Next, as illustrated in FIG. 1D, the metal layer forming the via 11 and the wiring pattern 15 is formed on the seed layer 7 by performing electroplating. Thereafter, as shown in FIG. 1E, the resist layer 5 is removed, and as shown in FIG. 1F, the seed layer 7 exposed through flash etching, quick etching, or the like is removed. By removing, the wiring pattern 15 is completed.

However, in the conventional method as described above, since the exposure and development processes of the plating resist and the etching and peeling processes are repeated, the process time increases and the manufacturing cost increases.

The present invention was created to solve the problems of the prior art as described above, the manufacturing process of the printed circuit board can reduce the manufacturing cost and lead time by eliminating the exposure, development, etching and peeling process Suggest.

A method of manufacturing a printed circuit board using a gravure printing method according to the present invention includes the steps of: (A) providing a base substrate having vias penetrating through the insulating layer; And (B) forming a circuit layer including a circuit pattern electrically connected to the vias on the top and bottom surfaces of the insulating layer by a gravure printing method.

As a preferred feature of the invention, the step (A), (i) printing the conductive bumps on the lower metal foil; (Ii) stacking an insulating layer on the lower metal foil so that the bumps protrude; (Iii) laminating an upper metal foil on the insulating layer to form a via by pressing the protrusion of the bump; And (iii) exposing the upper and lower end surfaces of the via by removing the lower metal foil and the upper metal foil.

In another preferred aspect of the present invention, the step (B) comprises (i) forming an upper circuit layer including a circuit pattern electrically connected to the via on the upper surface of the insulating layer by a gravure printing method using conductive ink. step; (Ii) drying the upper circuit layer; And (iii) forming a lower circuit layer including a circuit pattern electrically connected to the via on the lower surface of the insulating layer by a gravure printing method using conductive ink.

In addition, the method of manufacturing a printed circuit board using the gravure printing method according to the present invention, (A) providing a base substrate having a first via penetrating the first insulating layer; (B) forming a first circuit layer on the upper and lower surfaces of the first insulating layer by a gravure printing method including a circuit pattern electrically connected to the first via; (C) stacking a second insulating layer on the first circuit layer; (D) forming a second via through the second insulating layer in the second insulating layer; And (E) forming a second circuit layer electrically connected to the second via on the second insulating layer by a gravure printing method.

As another preferred feature of the present invention, the step (D) may comprise the steps of: (i) processing the via holes in the second insulating layer; (Ii) forming a seed layer on the surface of the second insulating layer including the inner wall of the via hole; (Iii) performing via peel plating on the seed layer with a lead; And (iii) removing the plating layer formed on the second insulating layer by the peel plating to form second vias.

In addition, the method of manufacturing a printed circuit board using the gravure printing method according to the present invention, (A) a base substrate having an insulating layer and a via formed through the insulating layer and the end surface is exposed to the surface of the insulating layer; Providing; And (B) forming a circuit layer including a circuit pattern electrically connected to the via on the top surface of the insulating layer by a gravure printing method.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to the manufacturing method of the printed circuit board using the gravure printing method according to the present invention, the exposure, development, etching and peeling process is omitted, which reduces the manufacturing cost and the lead time. This enables mass production of printed circuit boards.

Hereinafter, a preferred embodiment of a method of manufacturing a printed circuit board using a gravure printing method according to the present invention will be described in detail with reference to the accompanying drawings. Throughout the accompanying drawings, the same or corresponding components are referred to by the same reference numerals, and redundant descriptions are omitted. In this specification, terms such as top and bottom are used to distinguish one component from another component, and a component is not limited by the terms.

2 to 13 are diagrams showing a method of manufacturing a printed circuit board using a gravure printing method according to a preferred embodiment of the present invention in the process sequence.

First, a step of providing a base substrate 100 having a first via 130 penetrating the first insulating layer 150.

As shown in FIG. 2, the conductive bumps 130 are printed on the lower metal foil 110, and the first insulating layer 150 is stacked on the lower metal foil 110 so that the bumps 130 protrude. The bump 130 is printed by a screen print method. Screen printing is a method of printing the bump 130 through a conductive paste transfer process through a mask in which an opening is formed. The positions of the openings of the mask are aligned, and the conductive paste is applied to the upper surface of the mask. When the conductive paste is pushed using a squeegee or the like, the conductive paste is extruded through the opening and transferred to the land. In this case, the bumps 130 may be printed on a portion where the lands of the circuit layer are formed to be printed in a desired shape and height. It is preferable that the insulating layer used here is a resin layer of a B-stage state. The B-stage means an intermediate curing step of the resin, and is deformable by heating and pressing a predetermined size or more.

3 and 4, the upper metal foil 170 is stacked on the first insulating layer 150 to form the first via 130 by pressing the protrusion of the bump 130. The lower metal foil 110 and the upper metal foil 170 may be, for example, a thin metal plate made of a conductive metal such as gold, silver, copper, or nickel.

Subsequently, as shown in FIG. 5, the lower metal foil 110 and the upper metal foil 170 are removed to expose the top and bottom surfaces of the via. The lower metal foil 110 and the upper metal foil 170 are full-etched to expose the top and bottom surfaces of the first via 130. As a result, the lower metal foil 110 and the upper metal foil 170 stacked on the upper and lower portions of the first insulating layer 150 are removed.

Next, the first circuit layers 510 and 530 including the circuit patterns electrically connected to the first vias 130 are formed on the upper and lower surfaces of the first insulating layer 150 by gravure printing.

As illustrated in FIG. 6, a gravure printing method using a conductive ink on a first upper circuit layer 510 including a circuit pattern electrically connected to a first via 130 on an upper surface of the first insulating layer 150. To form.

The gravure printing apparatus used in the present embodiment is for printing a circuit layer on the first insulating layer 150, and includes a conductive ink supply unit 310, a cylinder roller 370, and a riding roller 350. , A press roller 390, and a doctor knife 380.

Here, the conductive ink supply unit 310 is for supplying the conductive ink 330 for circuit layer printing, and has a predetermined internal space for accommodating the conductive ink 330. In this case, the conductive ink 330 used may be a conductive ink containing a conductive metal powder such as gold, silver, copper, nickel, or lead paste, but is not limited thereto.

The cylinder roller 370 is for printing the circuit layer on the substrate using the conductive ink 330, and the intaglio groove 375 having a shape corresponding to the circuit layer is formed on the outer surface thereof. Part of the cylinder roller 370 is rotated while being partially locked to the conductive ink 330 supplied to the conductive ink supply unit 310 so that the conductive ink 330 is injected into the intaglio groove 375.

The riding roller 350 assists the injection of the conductive ink 330 into the intaglio groove 375 of the cylinder roller 370, and rotates the conductive ink 330 in the intaglio groove while rotating in the opposite direction to the cylinder roller 370. 375).

The press roller 390 applies pressure to the substrate passing between the cylinder roller 370 and the press roller 390 so that the conductive ink 330 injected into the intaglio groove 375 of the cylinder roller 370 is transferred to the substrate. As intended, it is configured to rotate in a direction opposite to the cylinder roller 370. In this case, the coating thickness and resolution of the circuit layer transferred to the base substrate 100 are determined according to the processing state of each roller, the composition of the conductive ink 330, the pressing force of the press roller 390, and the like. It is desirable to be properly controlled because it greatly affects the capacity and electrical properties. In particular, the stronger the pressing force of the press roller 390 is, the better the transition of the conductive ink 330 is, so that a good circuit layer can be formed. Therefore, the pressing force is preferably at least about 2.5 to 4 kg / cm ² or more. However, if the pressing force is too large, wrinkles may occur in the substrate, and it is preferable to properly adjust in consideration of this.

Finally, the doctor knife 380 serves as a steel plate blade to scrape off the excess conductive ink 330 on the outer surface of the cylinder roller 370 to prevent the transfer to the substrate, the cylinder roller 370 Is installed in contact with the outer surface. For example, the doctor knife 380 preferably has a thickness of about 0.15 to 1 mm, and is preferably made of carbon or stainless steel. In addition, the doctor knife 380 is preferably installed to be replaced.

As illustrated in FIG. 7, the first upper circuit layer 510 may be formed on the first insulating layer 150 by using the above-described gravure device. When the first upper circuit layer 510 is formed, the first upper circuit layer 510 is dried.

Next, as shown in FIG. 7, the first lower circuit layer 530 including a circuit pattern electrically connected to the first via 130 is formed on the bottom surface of the first insulating layer 150. It is formed by the gravure printing method using. Since the process of forming the first lower circuit layer 530 is the same or very similar to the process of forming the first upper circuit layer 510, a detailed description thereof will be omitted.

The double-sided substrate using the gravure printing method can be manufactured by the above-mentioned process. Although the substrate having the first via 130 made of the conductive paste has been described as the base substrate 100 for manufacturing the double-sided substrate, the present invention is not limited thereto. That is, a substrate having vias filled with a conductive metal may be used as the base substrate 100, and a double-sided substrate may be manufactured in the same manner. This method is described in detail in the build-up process described later.

Next, as shown in FIG. 9, a second insulating layer 700 is stacked on the first circuit layers 510 and 530.

Next, forming a second via 900 penetrating the second insulating layer 700 in the second insulating layer 700.

As shown in FIG. 10, a via hole 710 is processed in the second insulating layer 700. The via hole 710 may be processed in the second insulating layer 700 by a CNC (Computer Numerical Control) drill or a laser drill using, for example, a YAG laser or a CO ₂ laser. In this embodiment, the via hole 710 is processed using a CO ₂ laser.

Thereafter, as shown in FIG. 11, via fill plating is performed to fill the inside of the via hole 710 with a conductive metal. To this end, first, a seed layer may be formed on the surface of the second insulating layer 700 including an inner wall of the via hole 710, and the seed layer may be subjected to via peel plating using a lead line. The formation of the seed layer can be carried out in a known manner such as electroless plating or sputtering. The conductive metal may be, for example, gold, silver, copper, nickel or the like.

Next, as shown in FIG. 12, the second via 900 is formed by removing the plating layer 800 formed on the second insulating layer 700 by peel plating. The full etching may be performed to remove the plating layer 800 formed on the second insulating layer 700, and the second insulating may be performed without damaging the second via 900 filled in the via hole 710 by adjusting the etching amount. It is possible to remove only the plating layer 800 formed on the layer 700.

Next, as shown in FIG. 13, a second circuit layer electrically connected to the second via 900 is formed on the second insulating layer 700 by a gravure printing method. Since the process of forming the second circuit layer is the same and very similar to the process of forming the first circuit layers 510 and 530, detailed description thereof will be omitted.

In this embodiment, a process of manufacturing a four-layer printed circuit board by a gravure printing method has been described. However, one of ordinary skill in the art will readily understand that the present invention is not limited thereto and that it is possible to manufacture a multilayer printed circuit board having five or more layers using a gravure printing method.

According to the method of manufacturing a printed circuit board using the gravure printing method as described above, the exposure, development, etching and peeling processes are omitted, thereby reducing the manufacturing cost and reducing the lead time. Mass production of printed circuit boards is possible.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Therefore, such modifications or variations will have to belong to the claims of the present invention.

1 is a diagram illustrating a process of forming a via and a wiring pattern by the SAP method according to the prior art in the process order.

2 to 13 are views illustrating a method of manufacturing a printed circuit board having landless vias according to a preferred embodiment of the present invention in the order of process.

<Description of Major Symbols in Drawing>

100 Base board 110 Bottom metal foil

130 bumps 150 first insulating layer

170 Upper metal foil 310 Conductive ink supply part

330 Conductive Ink 350 Riding Roller

370 Cylinder Roller 375 Engraving

390 press roller 380 doctor knife

510 First lower circuit layer 530 First lower circuit layer

700 Second Insulation Layer 710 Via Hole

800 Plating Layer 900 Second Via

Claims (6)

(A) providing a base substrate having vias through the insulating layer; And (B) forming a circuit layer including a circuit pattern electrically connected to the via on the top and bottom surfaces of the insulating layer by gravure printing; Method of manufacturing a printed circuit board using a gravure printing method comprising a. The method of claim 1, Step (A) is (Iii) printing a conductive bump on the lower metal foil; (Ii) stacking an insulating layer on the lower metal foil so that the bumps protrude; (Iii) laminating an upper metal foil on the insulating layer to form a via by pressing the protrusion of the bump; And (Iii) removing the lower metal foil and the upper metal foil to expose the top and bottom surfaces of the via; Method of manufacturing a printed circuit board using a gravure printing method comprising a. The method of claim 1, Step (B) is, (Iii) forming an upper circuit layer including a circuit pattern electrically connected to the via on the upper surface of the insulating layer by a gravure printing method using conductive ink; (Ii) drying the upper circuit layer; And (Iii) forming a lower circuit layer including a circuit pattern electrically connected to the via on the bottom surface of the insulating layer by a gravure printing method using conductive ink; Method of manufacturing a printed circuit board using a gravure printing method comprising a. (A) providing a base substrate having a first via penetrating the first insulating layer; (B) forming a first circuit layer on the upper and lower surfaces of the first insulating layer by a gravure printing method including a circuit pattern electrically connected to the first via; (C) stacking a second insulating layer on the first circuit layer; (D) forming a second via through the second insulating layer in the second insulating layer; And (E) forming a second circuit layer electrically connected to the second via on the second insulating layer by gravure printing; Method of manufacturing a printed circuit board using a gravure printing method comprising a. The method of claim 4, wherein Step (D), (Vi) processing via holes in the second insulating layer; (Ii) forming a seed layer on the surface of the second insulating layer including the inner wall of the via hole; (Iii) performing via peel plating on the seed layer with a lead; And (Iii) forming a second via by removing the plating layer formed on the second insulating layer by the peel plating; Method of manufacturing a printed circuit board using a gravure printing method comprising a. (A) providing a base substrate having an insulating layer and a via formed through the insulating layer and having an end surface exposed to the surface of the insulating layer; And (B) forming a circuit layer including a circuit pattern electrically connected to the via on the top surface of the insulating layer by gravure printing; Method of manufacturing a printed circuit board using a gravure printing method comprising a.

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