KR101069893B1 - Method of manufacturing core substrate and manufacturing method for printed circuit board thereof using the same - Google Patents

Abstract

Disclosed are a core substrate manufacturing method and a printed circuit board manufacturing method using the same. Plating a metal layer on an upper surface of the first copper layer; Plating a second copper layer on an upper surface of the metal layer; And the core substrate manufacturing method comprising the step of etching the lower surface of the first copper layer, the thickness difference between the first copper layer and the second copper layer is reduced, the overall thickness of the core substrate can be reduced.

Core Board, Printed Circuit Board

Description

Method of manufacturing core substrate and manufacturing method for printed circuit board using the same {Method of manufacturing core substrate and manufacturing method for printed circuit board

The present invention relates to a method for manufacturing a core substrate and a method for manufacturing a printed circuit board using the same.

With the miniaturization, high density, and thinning of electronic components, research on thinning and high functionalization of semiconductor package substrates has been actively conducted. In particular, in order to implement a technology for stacking several semiconductor chips on a single substrate (MCP: Multi Chip Package) or for stacking several substrates on which a chip is mounted (PoP: Package on Package), It is necessary to develop a printed circuit board having thermal expansion behavior and excellent bending characteristics after mounting.

In addition, due to the recent increase in operating speed due to the high performance of the chip, the problem of heat generation is getting serious, so countermeasures are required. The most common method for responding to this need is to insert a metal plate such as a copper plate or an aluminum plate having excellent thermal conductivity into a core of a printed circuit board to manufacture a core board. In the case of the metal plate, the thermal expansion and thermal conductivity of the metal plate are excellent, thereby suppressing the thermal expansion behavior of the substrate and at the same time serving as a heat dissipation function.

Such printed circuit boards form vias for interlayer connection, and the core board is drilled in advance to form holes to communicate with the vias. In addition, if the position of the hole of the core substrate and the distance between the vias do not coincide with each other, a short defect may occur. Therefore, the hole should be formed in the core substrate larger than the size of the via due to the registration of the metal plates. Accordingly, the area of the metal plate for transferring heat is reduced, there is a fear that the thermal conductivity is reduced. In addition, the metal plate applied to the general core substrate increases the thickness of the core substrate.

The present invention provides a method for manufacturing a core substrate and a method for manufacturing a printed circuit board using the same, which can be reduced in thickness.

In addition, the present invention is to provide a method for manufacturing a core substrate that can reduce the distance between the core hole and the via, and a method for manufacturing a printed circuit board using the same.

According to an aspect of the invention, the step of plating a metal layer on the upper surface of the first copper layer; Plating a second copper layer on an upper surface of the metal layer; And etching the lower surface of the first copper layer.

In addition, according to another aspect of the invention, the step of plating a metal layer on the upper surface of the first copper layer; Plating a second copper layer on an upper surface of the metal layer; Etching the bottom surface of the first copper layer; Forming an insulating layer on the first copper layer and the second copper layer; And forming a circuit pattern on the insulating layer.

Here, after the plating of the second copper layer, the method may further include forming a core hole in the first copper layer, the metal layer, and the second copper layer.

Here, after etching the lower surface of the first copper layer, the method may further include forming an insulating layer on the first copper layer and the second copper layer.

The forming of the insulating layer may include: laminating a resin on the first copper layer and the second copper layer; And drying the resin by moving it between heated rollers.

Here, after the forming of the insulating layer, the method may further include forming a seed layer on the insulating layer.

Here, the resin may include a liquid teflon, liquid crystalline polymer polyester or polyimide.

Here, the metal layer may include an alloy of iron nickel, copper or aluminum.

According to the embodiment of the present invention, the thickness difference between the first copper layer and the second copper layer is reduced, thereby reducing the thickness variation between the upper and lower layers of the printed circuit board, and the thickness of the first copper layer can be reduced. Since the overall thickness can be reduced, the printed circuit board can be formed into a thin plate.

In addition, heat dissipation may be performed using the metal layer, and the gap between the via and the core hole may be reduced since it is not necessary to consider the occurrence of conventional metal matching. As a result, when the core hole is formed, the area of the first copper layer, the metal layer, and the second copper layer may be removed, and as the area of the core substrate for heat dissipation increases, the heat of the printed circuit board is increased. Release efficiency can be improved.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, when it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, an embodiment of a method of manufacturing a core board and a method of manufacturing a printed circuit board using the same according to the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals will be given and redundant description thereof will be omitted.

1 is a flow chart showing a core substrate manufacturing method according to an embodiment of the present invention, Figures 2 to 6 is a view showing a core substrate manufacturing method according to an embodiment of the present invention.

First, the metal layer 120 is plated on the upper surface of the first copper layer 110 (S110). For example, the metal layer 120 for improving heat dissipation and warpage on the upper surface of the first copper layer 110, such as a copper foil roll having a thickness of 18 um to 25 um in an electrolytic method, has a thickness of 3 um to 30 um. Form. The thicknesses of the first copper layer 110 or the metal layer 120 and the second copper layer 130 described below are exemplarily described for convenience of description, and are not limited thereto. It can be varied depending on the required characteristics of the substrate. In addition, the metal layer 120 may be formed of an alloy of iron nickel, copper, or aluminum. 2 illustrates a metal plate 120 plated on an upper surface of the first copper layer 110.

Next, the second copper layer 130 is plated on the upper surface of the metal layer 120 (S120). For example, the second copper layer 130 may be electroplated to a thickness of 3 μm to 10 μm on the upper surface of the metal layer 120. 3 illustrates a state in which the second copper layer 130 is plated on the upper surface of the metal layer 120.

Next, a core hole 135 is formed in the first copper layer 110, the metal layer 120, and the second copper layer 130 (S130). In order to form the core hole 135, for example, the photosensitive film 140 may be attached to, exposed to, and developed on the second copper layer 130, and the core hole 135 may be formed through an etching process.

In addition, the bottom surface of the first copper layer 110 is etched (S140). For example, the first copper layer 110 having a thickness of 18 um to 25 um may be half etched to form similar thicknesses of the first copper layer 110 and the second copper layer 130. . 4, the photosensitive film 140 is attached to the top surface of the second copper layer 130 to form a core hole 135, and the first copper layer 110 ′ is half-etched.

Next, an insulating layer 151 is formed on the etched first copper layer 110 ′ and the second copper layer 130 (S150). This can be done by laminating the resin 150 on the first copper layer 110 ′ and the second copper layer 130 (S151), and moving the resin 150 between the heated rollers 160 to dry it ( S153).

For example, the etched first copper layer 110 ′ and the second copper layer 130 are impregnated with a resin 150 such as liquid teflon (PTFE), liquid crystal polymer polyester (LCP), or polyimide (Pi). Alternatively, the resin 150 may be applied to the outside of the first copper layer 110 ′ and the second copper layer 130 and the inner wall of the core hole 135 by a thickness of 5 μm to 20 μm through a silk screen or the like. have. Next, the resin 150 may be subjected to primary drying using hot air drying. Next, the resin 150 may be planarized through the first copper layer 110 ′ and the second copper layer 130 having the resin 150 stacked therebetween, and the second drying may be performed between the heated rollers 160. have. 5 illustrates a state in which the first copper layer 110 ′ and the second copper layer 130 having the resin 150 laminated therebetween pass through the rollers 160.

The resin 150 is cured through drying to form the insulating layer 151, and the seed layer 170 is formed on the insulating layer 151 (S160). The seed layer 170 is subjected to a special treatment (IAR: Ion Assisted Reaction) such as a plasma ion beam source (IAR) on the surface of the insulating layer 151, and the seed layer of hydrophilic modification on the surface of the insulating layer 151. By being able to form 170, adhesion to the circuit pattern 210 formed later can be increased. In addition, the seed layer 170 is formed through electroless plating, and functions as an electrode to form a circuit pattern 210 that is electroplated on the surface of the insulating layer 151 which is not electrically conductive.

6 illustrates a state in which the seed layer 170 is formed on the insulating layer 151.

In the core substrate 100 formed as described above, the thickness difference between the first copper layer 110 ′ and the second copper layer 130 decreases, and the first copper layer 110 in which the first copper layer 110 ′ is initially prepared. ) Half of the thickness can be reduced the overall thickness.

The core substrate 100 manufactured according to the above embodiment is, for example, when the first copper layer 110 is applied to the copper foil roll, the core substrate 100 is formed of a roll-shaped core substrate 100 and cut into sheets of sheets. One core substrate 100 can be applied to the manufacture of the printed circuit board 200 described below.

7 is a flowchart illustrating a method of manufacturing a printed circuit board according to an embodiment of the present invention, and FIGS. 8 to 10 are views illustrating a method of manufacturing a printed circuit board according to an embodiment of the present invention.

The circuit pattern 210 is formed on the insulating layer 151 of the core substrate 100 formed by the above-described embodiment (S210). In order to form the circuit pattern 210, a tenting process of forming a copper foil (not shown) formed on the surface of the core substrate 100 and etching and patterning the same, an inkjet head (not shown) Various methods such as an inkjet process for directly printing conductive ink on the surface of the core substrate 100 may be used. 8 shows a circuit pattern 210 formed on the surface of the core substrate 100. In addition, the seed layer 170 formed on the surface of the insulating layer 151 may increase adhesion to the circuit pattern 210 and may function as an electrode to form the circuit pattern 210. Same as one. In addition, the circuit pattern 210 may be formed and the core hole 135 may be filled with metal, and the identification number 137 illustrated in FIG. 8 may be the same.

Next, the insulating layer 220 may be laminated on the core substrate 100. The insulating layer part 220 may be stacked on the surface of the core substrate 100 on which the circuit pattern 210 is formed, thereby protecting the circuit pattern 210.

As the core substrate 100 according to the present embodiment is applied, the thickness difference between the first copper layer 110 ′ and the second copper layer 130 is reduced to reduce the thickness variation between the upper and lower layers of the printed circuit board. The first copper layer 110 ′ is formed to be half the thickness of the first copper layer 110 prepared initially, so that the overall thickness of the core substrate 100 may be reduced, thereby forming the printed circuit board 200 in a thin plate. can do.

In addition, heat dissipation may be performed using the metal layer 120, and the gap between the via 251 and the core hole (see FIG. 6: 135) may be reduced since it is not necessary to consider generation of conventional metal matching. As a result, when the core hole 135 is formed, an area of the first copper layer 110, the metal layer 120, and the second copper layer 130 may be removed. Efficient removal of the core substrate can be reduced, thereby improving heat dissipation efficiency of the printed circuit board 200.

For example, when fabricating four or more layers of the printed circuit board 200, the outer insulation layer 230 on which the copper foil 240 is laminated may be laminated on the insulation layer 220. In addition, the via hole 250 may be formed in the outer insulation layer 230 by using a laser. 9, the outer insulation layer 230 is stacked on the core substrate 100, and the via hole 250 is formed. The via hole 250 may be formed of a via 251 that fill-fills and enables electrical connection between layers.

The outer circuit pattern 260 may be formed on the copper foil 240, and the outer circuit pattern 260 may apply the method of forming the circuit pattern 210 described above, and after the outer circuit pattern 260 is formed, the copper foil ( 240 may be etched. In order to protect the outer circuit pattern 260, the second solder resist 270 may be stacked on the outer side of the outer insulating layer 230.

For example, bumps 280 may be formed on the vias 251. The bump 280 serves as a terminal through which the circuit pattern 210 and the outer circuit pattern 260 are connected to an external component such as a semiconductor chip or a motherboard. The bump 280 may be formed using various methods such as an inkjet process for directly printing conductive ink. A printed circuit board 200 formed by such a manufacturing method is shown in FIG.

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 or scope of the invention as defined in the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

Many embodiments other than the above-described embodiments are within the scope of the claims of the present invention.

1 is a flow chart showing a core substrate manufacturing method according to an embodiment of the present invention.

2 to 6 is a view showing a core substrate manufacturing method according to an embodiment of the present invention.

7 is a flowchart illustrating a method of manufacturing a printed circuit board according to an embodiment of the present invention.

8 to 10 are views showing a method of manufacturing a printed circuit board according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: core substrate 110, 110 ': first copper layer

120: metal layer 130: second copper layer

135: core hole 140: photosensitive film

150: resin 151: insulating layer

170: seed layer 200: printed circuit board

210: circuit pattern 220: insulating layer portion

230: outer insulation layer 240: copper foil

250: Via Hole 251: Via

260: outer circuit pattern 270: second solder resist

Claims (14)

Plating a metal layer on an upper surface of the first copper layer; Plating a second copper layer on an upper surface of the metal layer; Forming core holes in the first copper layer, the metal layer, and the second copper layer; Etching the bottom surface of the first copper layer; And forming an insulating layer on the outer side of the first copper layer and the second copper layer and on the inner wall of the core hole. delete delete The method of claim 1, Forming the insulating layer, Stacking a resin on the first copper layer and the second copper layer; And And drying the resin by moving the resin between the heated rollers. 5. The method of claim 4, After forming the insulating layer, And forming a seed layer on the insulating layer. 5. The method of claim 4, The resin is a core substrate manufacturing method comprising a liquid teflon, liquid crystal polymer polyester or polyimide. The method of claim 1, The metal layer is a core substrate manufacturing method comprising an alloy of iron nickel, copper or aluminum. Plating a metal layer on an upper surface of the first copper layer; Plating a second copper layer on an upper surface of the metal layer; Forming core holes in the first copper layer, the metal layer, and the second copper layer; Etching the bottom surface of the first copper layer; Forming an insulating layer on an outer side of the first copper layer and the second copper layer and on an inner wall of the core hole; And The method of manufacturing a printed circuit board comprising the step of forming a circuit pattern on the insulating layer. delete delete The method of claim 8, Forming the insulating layer, Stacking a resin on the first copper layer and the second copper layer; And The method of manufacturing a printed circuit board comprising the step of moving the resin between the heated roller to dry. The method of claim 11, After forming the insulating layer, Forming a seed layer on the insulating layer further comprising the step of manufacturing a printed circuit board. The method of claim 11, The resin is a manufacturing method of a printed circuit board comprising a liquid teflon, liquid crystalline polymer polyester or polyimide. The method of claim 8, The metal layer is a method of manufacturing a printed circuit board comprising an alloy of iron nickel, copper or aluminum.

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