KR100925761B1 - Fabrication method of printed circuit board - Google Patents

Abstract

Disclosed is a method of manufacturing a printed circuit board. According to an embodiment of the present invention, manufacturing a mold having a fine concave-convex corresponding to the roughness (roughness) to be transferred to the substrate formed on the inner surface; Filling a thermoplastic material into the mold; Compressing and molding the thermoplastic material filled in the mold to prepare a substrate on which the roughness corresponding to the fine unevenness is surface-transferred; And forming a circuit wiring on the surface of the substrate to which the fine roughness is transferred. According to the present invention, there is an advantage in that a substrate having fine roughness formed on the surface of the substrate can be easily produced without an additional process for roughening.

Printed circuit board, roughness, mold, compression molding.

Description

Fabrication method of printed circuit board

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board, and more particularly, to a manufacturing method of a substrate having fine roughness formed on a surface thereof.

A printed circuit board (PCB) is a circuit wiring formed of a conductive material on both sides of a substrate made of an insulating material, and can be freely implemented wiring patterns suitable for the characteristics of electronic devices. It is becoming.

Recently, with the miniaturization and thinning of electronic products, there is an increasing demand for thin circuit boards in which microcircuits are implemented. In addition, reliability for maintaining stable electrical characteristics under thermal and physical shocks is required for printed circuit boards. Therefore, the adhesion between the substrate and the circuit wiring in the manufacture of the printed circuit board is an important part of the product reliability. In particular, the adhesive force between the inner layer substrate and the circuit wiring on which the inner layer circuit is implemented is also an important factor to prevent defects caused by irregular oxidation during thermal shock such as soldering parts or chip molding in the outer layer.

Circuit wiring in a conventional printed circuit board has been implemented through a process such as plating, exposure, development, peeling, etching on a copper clad laminate (CCL) consisting of an insulating material and a copper foil. However, in recent years, due to the light and thin shortening trend of electronic devices, it is required to implement a microcircuit along with the development of a high-performance insulating material in order to improve the signal transmission speed, and overcome the limitations of the conventional wet process to meet the demand of the microcircuit implementation. The research on the wiring forming method using a semi-additive plating (SAP), a laser or an inkjet method is being conducted. The wire forming method using the SAP method, the laser method, or the inkjet method has attracted attention recently because it has the convenience and accuracy in the process of forming a fine circuit more easily or more accurately than the conventional method.

However, since the wiring forming method as described above directly forms the circuit wiring on the substrate through plating or spraying of conductive ink, the circuit adhesion depends on the adhesive strength between the substrate and the plating or the substrate and the ink. However, the adhesive strength between the substrate and the circuit wiring according to the method is still far below the level of the adhesive strength between the insulating layer and the copper foil, which is realized from the copper foil laminate produced by thermocompression bonding.

In order to overcome the above-described problems and to increase the adhesion between the substrate and the circuit wiring, a method of forming fine roughness on the surface of the substrate is used. According to the related art, the roughening method for increasing the adhesive force between the substrate and the circuit wiring includes a wet method using a chemical treatment, a dry method using a plasma, an ion beam treatment, and a method of introducing a fine filler. In the wet method, since the surface treatment by chemicals is easy, it is mainly used, but there are problems of environmental pollution by chemicals and problems of liquid management. In the dry method using a plasma or the like, an environmentally friendly method for improving adhesion by surface reaction by an ionized surface treatment gas without chemicals is used, but an unpredictable roughness is formed to implement a fine circuit. There is a difficulty in controlling the fine roughness. In particular, the dry method is a method in which compatibility with the conductive ink for wiring is problematic when the inkjet method is used for forming the circuit wiring. In addition, the introduction method of the fine filler is a method of forming the roughness by detaching the fine filler on the surface of the substrate, but since the roughness formation depends on the size and shape of the filler, there is a limit to the control of the fine roughness.

In addition, since the above-described conventional roughness forming method all adds an additional additional process, the manufacturing process of the printed circuit board becomes complicated and the manufacturing cost also increases.

Accordingly, the present invention provides a method of manufacturing a printed circuit board that can increase the adhesive force between the substrate and the circuit wiring without any additional process for roughness treatment.

The present invention is a simple method of inserting a thermoplastic material into a mold having fine concavities and convexities, and compression molding or injection molding, and it is possible to form fine roughness on the surface of the substrate simultaneously with fabrication of the substrate, thereby simplifying the manufacturing process and reducing the manufacturing cost. Provides a method of making a circuit board.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the invention, the step of manufacturing a mold having a fine concavo-convex corresponding to the roughness (roughness) to be transferred to the substrate formed on the inner surface; Filling a thermoplastic material into the mold; Compressing and molding the thermoplastic material filled in the mold to prepare a substrate on which the roughness corresponding to the fine unevenness is surface-transferred; And forming a circuit wiring on a surface of the substrate to which the fine roughness is transferred.

Here, the thermoplastic material may be filled into the mold in a powder state.

Here, the thermoplastic material is a liquid crystal polymer (LCP), polyetherimide (PEI, polyetherimide), polyethersulfone (PES, polyethersulfone), polyether ether ketone (PEEK, polyetheretherketone) and polytetrafluoroethylene (PTEE). , polytetrafluoroethylene).

Here, the thermoplastic material may be a composite of a thermoplastic polymer and a functional ceramic filler.

Here, the functional ceramic filler may include crystalline silica (crystalline SiO ₂ ), fused silica (fused SiO ₂ ), silicon nitride (SiN, silicon nitride), boron nitride (BN), aluminum nitride (AlN, aluminum). nitride) and alumina (Al ₂ O ₃ ).

Here, the composite may be added to the functional ceramic filler 70% by weight (wt%) or less.

Here, the fine concavo-convex may be formed on the inner surface of the mold so that the roughness can be transferred to the entire surface of the surface of the substrate corresponding to the surface on which the circuit wiring is to be formed.

Here, the fine concavo-convex may be formed on the inner surface of the mold so that the roughness can be transferred only to a portion of the substrate surface corresponding to the position where the circuit wiring is to be formed.

Here, the forming of the circuit wiring may be performed by directly forming the circuit wiring at a predesigned wiring position using an inkjet method.

Here, the thermoplastic material is a composite of a thermoplastic polymer and a functional ceramic filler, but before the step of filling the thermoplastic material, the step of putting the composite of the thermoplastic polymer and the functional ceramic filler in an agitator may be further stirred.

According to another aspect of the invention, the step of manufacturing a mold formed on the inner surface of the fine irregularities corresponding to the roughness (roughness) to be transferred to the substrate; Injecting a thermoplastic material into the mold; Injection molding the thermoplastic material injected into the mold to prepare a substrate on which the roughness corresponding to the fine unevenness is surface-transferred; And forming a circuit wiring on a surface of the substrate to which the fine roughness is transferred.

Here, the thermoplastic material may be injected into the mold in a molten state.

Here, the thermoplastic material is a liquid crystal polymer (LCP), polyetherimide (PEI, polyetherimide), polyethersulfone (PES, polyethersulfone), polyether ether ketone (PEEK, polyetheretherketone) and polytetrafluoroethylene (PTEE). , polytetrafluoroethylene).

Here, the thermoplastic material may be a composite of a thermoplastic polymer and a functional ceramic filler.

Here, the functional ceramic filler may include crystalline silica (crystalline SiO ₂ ), fused silica (fused SiO ₂ ), silicon nitride (SiN, silicon nitride), boron nitride (BN), aluminum nitride (AlN, aluminum). nitride) and alumina (Al ₂ O ₃ ).

Here, the composite may be added to the functional ceramic filler 70% by weight (wt%) or less.

Here, the fine concavo-convex may be formed on the inner surface of the mold so that the roughness can be transferred to the entire surface of the surface of the substrate corresponding to the surface on which the circuit wiring is to be formed.

Here, the fine concavo-convex may be formed on the inner surface of the mold so that the roughness can be transferred only to a portion of the substrate surface corresponding to the position where the circuit wiring is to be formed.

Here, the forming of the circuit wiring may be performed by directly forming the circuit wiring at a predesigned wiring position using an inkjet method.

According to the manufacturing method of the printed circuit board according to the present invention, there is an effect that can increase the adhesive force between the substrate and the circuit wiring without an additional process for roughness processing.

In addition, the present invention is a simple method of inserting a thermoplastic material into a mold having fine concavities and convexities, and compression molding or injection molding, and it is possible to form fine roughness on the surface of the substrate simultaneously with fabrication of the substrate, thereby simplifying the fabrication process during fabrication of a printed circuit board. Therefore, it is possible to reduce the production cost.

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 modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if 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.

Terms such as first and second 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. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

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.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and are not construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart schematically illustrating a method of manufacturing a substrate having fine roughness formed on a surface thereof when using a compression molding method according to an embodiment of the present invention, and FIGS. 2A to 2D are each a manufacturing step illustrated in FIG. 1. 3 is a view showing an increase in the adhesion area between the substrate and the circuit wiring in the substrate with fine roughness.

Hereinafter, a method of manufacturing the printed circuit board of FIG. 1 will be described with reference to FIGS. 2A to 2D and 3.

First, referring to step S110 of FIG. 1, a metal mold having fine irregularities corresponding to roughness to be transferred to a substrate is formed on an inner surface thereof.

The mold 110 may include, for example, fine concavities and convexities 20, first concave and convexities 20, and second concave and convexities on the inner surface of the upper mold 110a and the inner surface of the lower mold 110b, as shown in FIG. 2A. 20b)) can be manufactured in the form formed. This considers a double-sided printed circuit board in which circuit wiring is formed on both sides of the board. Therefore, when considering a single-sided printed circuit board in which the circuit wiring is formed only on one surface of the substrate, it is apparent that the fine unevenness 20 may be formed only on the inner surface of the mold corresponding to the one surface.

That is, the fine unevenness 20 is sufficient if the circuit wiring is formed on the inner surface of the mold 110 corresponding to the corresponding surface to be patterned on the substrate surface. At this time, the fine concave-convex 20 may be formed on all of the inner surface of the mold 110 so that the roughness can be transferred to the entire surface of the surface of the substrate surface to be formed circuit wiring. Of course, the fine concave-convex 20 may be selectively formed only on a portion of the inner surface of the mold 110 so that the roughness can be transferred only to a portion of the substrate surface corresponding to the position where the circuit wiring is actually formed.

The mold 110 manufactured in the form of the former (the form in which the fine concavo-convex 20 is formed on the entire inner surface of the mold 110) has an advantage that it can be used universally when manufacturing a substrate having fine roughness, The mold 110 manufactured in the latter form (a form in which the fine concavo-convex 20 is formed only on a specific portion of the inner surface of the mold 110) is utilized for the production of a substrate of a specific product, thereby designing a design specification (substrate) of each product. Material, process conditions, the width and thickness of the required circuit wiring, and thus the required roughness, etc.) has the advantage of manufacturing a more suitable and specialized substrate. Therefore, the size of the fine concavo-convex 20 formed on the inner surface of the mold 110 will be determined according to the product characteristics and design specifications as described above. For example, the fine concave-convex 20 may be formed on the inner surface of the mold 110 with a height and a spacing of approximately several μm to several tens of micrometers corresponding to the size of roughness required on the substrate surface. In addition, the inner surface of the mold 110 may be formed while having different sizes and shapes of the fine concavo-convex 20 for each part. That is, the determination regarding the formation position, shape, size, etc. of the fine concavo-convex 20 as described above may be variously changed and changed according to the selection of the designer considering the application.

Referring to step S120 of FIG. 1, a thermoplastic material (see identification number 120a of FIG. 2B) is filled into a mold manufactured in advance as described above. As described above, in the present invention, a thermoplastic material is used as the substrate material.

When using a thermoplastic material as a substrate material, there are the following advantages. First, when the thermoplastic material is used as the substrate material, it is possible to manufacture the substrate thin and long. This is because a substrate made of a thermoplastic material is much smaller than a substrate made of another material (eg, a substrate made of a ceramic material) even when a thin and long substrate is formed. In addition, when a thermoplastic material is used as the substrate material, there is an advantage in that the substrate can be manufactured by a method of compression molding or injection molding. The compression molding or injection molding method has an advantage of molding (manufacturing) the substrate integrally by inserting a material into a prefabricated mold, thereby greatly contributing to the reduction of the substrate manufacturing cost according to mass production. In addition, compression molding or injection molding is a method having design flexibility in that a product having various designs can be manufactured according to a shape of a mold designed in advance.

Accordingly, when the thermoplastic material is used as the substrate material, various advantages, such as the simplification of the substrate manufacturing process, the reduction of the manufacturing cost, and the design flexibility, can be secured as described above. However, there are some requirements that are required to function the thermoplastic material as the substrate material. For example, the thermoplastic material used as the substrate material needs to have an appropriate level of mechanical strength required to function as a substrate, a support, an appropriate level of thermal conductivity in consideration of heat dissipation characteristics, heat resistance at high temperatures, and the like. will be.

Thermoplastic materials with such heat resistance and mechanical strength include polyetherimide (PEI, polyetherimide), polyethersulfone (PES, polyethersulfone), polyetheretherketone (PEEK, polyetheretherketone), and polytetrafluoroethylene. Thermoplastic polymer materials such as (PTFE, polytetrafluoroethylene) and liquid crystal polymer (LCP) may be used. In particular, the liquid crystal polymer (LCP) has excellent features such as heat resistance, rigidity, dimensional stability, molding processability, etc., and is inexpensive in terms of price, and is highly regarded in the electronic component field among high-functional engineering plastics.

Alternatively, a composite of the above-mentioned thermoplastic polymer and functional ceramic filler may be used as the thermoplastic material. When the functional ceramic filler is added to the thermoplastic polymer, the thermal conductivity is improved, and thus the heat dissipation characteristics can be expected to be improved in the manufactured substrate. These functional ceramic fillers include, for example, the thermal conductive material having an excellent low thermal expansion, the crystalline silica (crystalline SiO _2), molten silica (fused SiO _2), silicon nitride (SiN, silicon nitride), boron Nitride (BN), aluminum nitride (AlN), alumina (Al ₂ O ₃ ), or the like may be used.

Therefore, at this time, the process of stirring in a stirrer for a predetermined time so that the functional ceramic filler in the thermoplastic polymer material can be evenly dispersed and mixed may be preceded before this step (filling the thermoplastic material in the mold). However, the ratio of the functional ceramic filler added to the thermoplastic polymer is preferably 70% by weight (wt%). If the functional ceramic filler is added at a higher ratio, it may adversely affect the thermoplastic properties of the composite.

In this case, the thermoplastic material filled in the mold may be in a powder state. For example, a powdered thermoplastic material can be filled into a mold heated to 330 ° C. However, this is because the substrate fabrication process according to the embodiment of the present invention is performed according to the compression molding method. Therefore, this may vary depending on the molding method used for fabricating the substrate (for example, in FIG. 4, the injection molding method is used to fill the molten thermoplastic material into the mold).

Referring to step S130 of FIG. 1, a thermoplastic material filled in a mold is compression molded to form a substrate (see identification number 120 of FIG. 2C) having a fine roughness (refer to identification numbers 30a and 30b of FIG. 2C) on a surface thereof. To make.

The compression molding method is a method in which a powder material is put in a preheated mold, pressed with a press, and heated at the same time. In particular, the process cost is lower than that of other molding methods, and the molding process uses a compressor. Therefore, since it is made under high temperature and high pressure, the molecular molecules of the powder are tightly bound, thereby making it possible to manufacture a substrate having better mechanical strength and heat resistance. Therefore, according to the compression molding method, it is not necessary to add glass cloth or the like to the substrate material in order to secure the mechanical strength of the substrate to an appropriate level unlike the conventional art. Accordingly, the effect of reducing material costs can be expected. Fine concavities and convexities formed on the inner surface of the mold through the compression molding process are transferred to the surface of the substrate, whereby fine roughness corresponding to the fine concavities and convexities is formed on the substrate surface.

Referring to step S140 of FIG. 1, a printed circuit board is manufactured by forming circuit wiring on a surface of a substrate to which fine roughness is transferred.

The circuit wiring may be formed on the surface of the substrate at a predesigned line width at a predesigned position, and the method for forming the circuit wiring may be, for example, a semi-additive plating method, a laser printing method, an inkjet printing method, or the like. Of course, various methods can be used without particular limitation. However, FIG. 2D specifically illustrates a case in which the method of directly forming the circuit wiring 130 by directly spraying the conductive ink 40 at the position where the inkjet nozzle 200 is to be formed on the surface of the substrate according to the inkjet method is used. It is assumed and shown. Since the inkjet method directly forms the circuit wiring by spraying conductive ink at the position where the wiring is to be formed, there is simplicity in process compared to the classical wiring method in which the circuit wiring is formed through various steps such as plating, masking, and etching. Of course, there is an advantage that can form a more precise and fine circuit wiring.

At this time, the adhesive strength between the substrate and the circuit wiring is greatly improved by the fine roughness formed on the substrate surface. This is because the adhesion area between the substrate and the circuit wiring increases greatly with the fine roughness formed on the surface of the substrate. This can be easily confirmed through FIG. 3. In the case of FIG. 3 (b) having fine roughness formed on the surface of the substrate, the adhesive area between the substrate and the circuit wiring is more than doubled compared to FIG. 3 (a) in which roughness is not formed on the substrate surface. . In addition to the increase in the adhesion area, when the fine roughness is formed on the surface of the substrate, the adhesion of the circuit wiring (that is, the adhesion between the conductive material as the circuit wiring and the surface of the roughened substrate) due to the anchor effect caused by the fine roughness. Can be increased significantly.

As described above, according to an exemplary embodiment of the present invention, a method of compressing and molding a thermoplastic material using a mold manufactured in advance in a form in which fine unevenness is formed on an inner surface thereof, and simultaneously transfers fine roughness to the surface of the substrate during the manufacturing process of the substrate. It can be formed, and does not need to go through an additional process for roughening the surface of the substrate as in conventional wet and dry methods. Therefore, according to the present invention, it is possible to form fine roughness on the surface of the substrate simultaneously with fabrication of the substrate even without using an additional roughening process, thereby simplifying the entire manufacturing process of the printed circuit board and reducing the production cost thereof. There is an advantage. In addition, by varying the shape, size, area of the mold, and the size, shape, and formation position of the fine concavities and convexities, the surface of the substrate may be changed according to various design specifications (particularly, circuit line width and spacing required for each product). It is easy to manufacture a substrate having a fine roughness having various sizes, intervals, position ranges, and shapes.

As described above, the printed circuit board manufactured in such a manner that the fine roughness is transferred to the surface of the substrate is greatly improved in adhesion between the substrate and the circuit wiring, and thus, higher stability and operational reliability may be expected in electronic devices and electronic products including the same. It becomes possible.

Hereinafter, a method of manufacturing a substrate having fine roughness formed on a surface thereof according to another embodiment of the present invention will be described with reference to FIG. 4. However, in describing the exemplary embodiment of FIG. 4, description of contents that may overlap with those of FIGS. 1 to 3 described above will be omitted.

4 is a flowchart schematically illustrating a method of manufacturing a substrate having fine roughness formed on a surface thereof when using an injection molding method according to another exemplary embodiment of the present invention.

4 is a flowchart showing steps S410 to S440 as a method of manufacturing a substrate having fine roughness according to another embodiment of the present invention, but step S410 (manufacturing step of a mold having fine unevenness) is performed in FIG. 1. S110 and step S440 (circuit wiring forming step) correspond to essentially the same manufacturing steps as step S140 of FIG. In addition, the contents of steps S420 and S430 of FIG. 4 also correspond substantially to those of steps S120 and S130 of FIG. 1 (that is, using a thermoplastic material as the substrate material).

However, another embodiment of the present invention uses an injection molding method, unlike in FIG. 1 (using a compression molding method), for manufacturing a substrate having fine roughness formed on a surface thereof. For this reason, after injecting a thermoplastic material into the mold through step S420 of FIG. 4, a substrate having fine roughness formed on the surface is manufactured by injection molding the thermoplastic material injected into the mold through step S430 of FIG. 4. .

In the case of using the injection molding method when manufacturing a substrate having fine roughness as in the present embodiment, first, a thermoplastic material is heated to a molten state, and then a thermoplastic material in a molten state is injected into a previously manufactured mold and cured. The substrate obtained by transferring the desired fine roughness to the surface can be produced.

The above-mentioned injection molding method can also be easily mass-produced to reduce the manufacturing cost, and there is an advantage in that a substrate of various designs and roughnesses can be manufactured according to the shape of the mold.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be readily understood that modifications and variations are possible.

1 is a flowchart schematically showing a method of manufacturing a substrate having fine roughness formed on a surface when using a compression molding method according to an embodiment of the present invention.

2a to 2d respectively correspond to the fabrication steps shown in FIG.

3 is a view for showing the increase in the adhesion area between the substrate and the circuit wiring in the substrate formed with fine roughness.

4 is a flowchart schematically showing a method of manufacturing a substrate having fine roughness formed on a surface thereof when using an injection molding method according to another exemplary embodiment of the present invention.

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

110: mold 120a: thermoplastic material

120: substrate 130: circuit wiring

20: fine unevenness 30: fine roughness

Claims (12)

Manufacturing a mold having fine unevenness formed on an inner surface corresponding to roughness to be transferred to a substrate; Filling a thermoplastic material into the mold; Filling the thermoplastic material filled in the mold to prepare a substrate on which surface roughness corresponding to the unevenness is transferred; And       Forming circuit wiring on a surface of the substrate to which the fine roughness is transferred;        The thermoplastic material is a composite of a thermoplastic polymer and a functional ceramic filler,        And the fine unevenness is formed on an inner surface of the mold so that illuminance can be transferred to an entire surface of a surface of the substrate corresponding to a surface on which the circuit wiring is to be formed. The method of claim 1, And the thermoplastic material is filled into the mold in a powder state.       The method of claim 1,       Producing the substrate      Printed circuit board manufacturing method characterized in that the compression molding of the thermoplastic material in the mold. The method of claim 1, Producing the substrate Printed circuit board manufacturing method, characterized in that for injection molding the thermoplastic material in the mold. The method of claim 1, Printed circuit board manufacturing method, characterized in that the thermoplastic material is injected into the mold in a molten state. The method of claim 1, The thermoplastic material is liquid crystal polymer (LCP), polyetherimide (PEI, polyetherimide), polyethersulfone (PES, polyethersulfone), polyetheretherketone (PEEK, polyetheretherketone) and polytetrafluoroethylene (PTEE, polytetrafluoroethylene) A printed circuit board manufacturing method, characterized in that any one of). The method of claim 1, The functional ceramic filler may include crystalline silica (crystalline SiO ₂ ), fused silica (fused SiO ₂ ), silicon nitride (SiN, silicon nitride), boron nitride (BN), aluminum nitride (AlN) And alumina (Al ₂ O ₃ ). delete delete The method of claim 1, The inner surface of the mold is the manufacturing method of the printed circuit board, characterized in that the fine concavo-convex is formed so that the roughness can be transferred only to the portion of the substrate surface corresponding to the position where the circuit wiring is to be formed. The method of claim 1, Forming the circuit wiring, A method of manufacturing a printed circuit board, wherein the circuit wiring is directly formed at a predesigned wiring position using an inkjet method. The method of claim 1, The thermoplastic material is a composite of a thermoplastic polymer and a functional ceramic filler, but before the step of filling the thermoplastic material, The method of manufacturing a printed circuit board further comprising the step of stirring the composite of the thermoplastic polymer and the functional ceramic filler in a stirrer.

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