KR20180130905A - Method for manufacturing flexible printed circuit board and flexible printed circuit board manufactured by the method - Google Patents

Abstract

Provided are a method for manufacturing flexible printed circuit board, which laminates base sheets composed of Teflon films with heat resistance and a low dielectric constant to prevent loss of a high frequency signal while minimizing dielectric loss sue to the high frequency signal, and a flexible printed circuit board manufactured by the same. The method according to the present invention comprises the steps of: preparing a base sheet which is a Teflon film having a thin film pattern formed on one surface thereof; preparing an adhesive sheet; laminating a plurality of base sheets and the adhesive sheets; and heating and pressing a laminate having the plurality of base sheets and the adhesive sheet laminated thereon.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a flexible printed circuit board and a flexible printed circuit board manufactured by the method.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible printed circuit board manufacturing method and a flexible printed circuit board manufactured thereby. More particularly, the present invention relates to a flexible printed circuit board manufacturing method having heat resistance and ductility and a flexible printed circuit board manufactured thereby.

Generally, a printed circuit board is a substrate that can be bent flexibly by forming a circuit pattern on a thin insulating film, and is widely used in portable electronic devices and automation devices or display products that require flexibility and flexibility in use.

Generally, a printed circuit board is manufactured by bonding or die casting a copper foil to a polyimide (PI) film. At this time, since the polyimide film has characteristics such as high mechanical strength, heat resistance, insulation, and solvent resistance, it is widely used as a base substrate of a printed circuit board.

On the other hand, as the use of a service for transmitting large amount of information in real time such as video call, movie appreciation, real time relay and the like is increasing, the portable terminal has circuits for transmitting large capacity information using a high frequency band (for example, Respectively.

However, when a high-frequency signal is transmitted using a printed circuit board made of a polyimide film, a signal loss of a high-frequency signal is generated due to inherent dielectric loss of the material.

That is, since the polyimide film has a high dielectric constant, a dielectric loss occurs during transmission and reception of a high frequency signal, and a loss of a high frequency signal occurs thereby causing a problem of interruption in using a service such as video call, movie appreciation, have.

In addition, a printed circuit board fabricated from a film having a low dielectric constant can minimize the loss of high frequency signals, but since the melting temperature is low and the heat resistance is lowered, There is a problem that the surface melts due to the high temperature of about 250 캜 and defects occur.

In addition, since a film having a low dielectric constant and high heat resistance is formed at a high price, the manufacturing cost of the printed circuit board is increased, and the competitive power in the market is lost.

Korean Patent Publication No. 10-2016-0097948 (Name: Flexible Printed Circuit Board and Method for Manufacturing the Same)

Disclosure of Invention Technical Problem [8] The present invention has been proposed in order to solve the problems of the related art described above, and it is an object of the present invention to provide a base sheet comprising a base sheet composed of a Teflon film having a heat resistance and a low dielectric constant to minimize loss of high- A method of manufacturing a flexible printed circuit board and a flexible printed circuit board manufactured thereby.

That is, the present invention provides a flexible printed circuit board fabrication method in which a base sheet is formed by forming a circuit pattern on a Teflon substrate having excellent heat resistance and dielectric properties, and a plurality of base sheets are laminated to form a high heat resistance and a low dielectric constant characteristic. It is an object of the present invention to provide a flexible printed circuit board manufactured thereby.

According to another aspect of the present invention, there is provided a method of manufacturing a flexible printed circuit board, comprising: preparing a base sheet, which is a Teflon film having a thin film pattern formed on one surface thereof; preparing an adhesive sheet; Stacking the sheets; And a step of heating and pressing the stacked body having the plurality of base sheets and the adhesive sheet laminated thereon.

The step of preparing the base sheet includes a step of adhering a guide film to one surface of the Teflon film and a step of forming a thin film pattern on the other surface of the Teflon film. At this time, the guide film may be a polyethylene terephthalate (PET) film.

In the step of sticking the guide film, a silicone-based adhesive film can be interposed between the Teflon film and the guide film.

The step of preparing the base sheet may further include forming a plurality of first guide holes in the base sheet.

The step of preparing the base sheet may further include forming at least one via hole penetrating the Teflon film, the guide film and the thin film pattern.

The step of preparing the adhesive sheet includes forming a plurality of second guide holes passing through the adhesive sheet and the plurality of second guide holes are formed at positions corresponding to the plurality of first guide holes formed in the base sheet .

The step of preparing the adhesive sheet may include forming one or more via holes passing through the adhesive sheet.

The adhesive sheet may be a CPP (Casted polypropylene) film having a multilayer structure in which an adhesive layer is formed on at least one side, or a single-layer adhesive film containing at least one of polyethylene, polypropylene and polyimide.

In the laminating step, a plurality of base sheets and an adhesive sheet may be alternately laminated so that an adhesive sheet can be interposed between the base sheet and the other base sheet.

The step of laminating includes the steps of laminating a base sheet on a jig through a guide pin of a jig in a first guide hole, removing the guide film of the base sheet, and passing the guide pin of the jig through the second guide hole, And laminating the adhesive sheet on top of the adhesive sheet.

The method of manufacturing a flexible printed circuit board according to an embodiment of the present invention may further include a step of preliminarily bonding the stacked body by applying water pressure to the stacked body before the step of heating and pressing the stacked body.

The method of manufacturing a flexible printed circuit board according to an embodiment of the present invention may further include forming a via hole through the base sheet and the adhesive sheet after the bonding step and forming a connection pattern inside the via hole .

In order to achieve the above object, a flexible printed circuit board according to an embodiment of the present invention includes a laminate in which a base sheet and an adhesive sheet are alternately laminated, and a circuit pattern formed in the laminate, and the base sheet includes a Teflon film .

Base sheet Teflon film and a thin film pattern formed on one side of the Teflon film.

The circuit pattern may include a plurality of thin film patterns formed on one surface of the Teflon film and disposed on the inner and upper surfaces of the laminate, and a connection pattern connecting the plurality of thin film patterns. At this time, the connection pattern may be formed on the inner wall surface of the via hole formed through the laminate, or may be filled in the via hole.

The adhesive sheet may be a CPP (Casted polypropylene) film having a multilayer structure in which an adhesive layer is formed on at least one side, or a single-layer adhesive film containing at least one of polyethylene, polypropylene and polyimide.

According to the present invention, a method of manufacturing a flexible printed circuit board and a flexible printed circuit board manufactured thereby can minimize the dielectric loss due to a high frequency signal by stacking a plurality of base sheets having high heat resistance and low dielectric constant, Can be prevented.

The flexible printed circuit board manufacturing method and the flexible printed circuit board manufactured by the method can also be applied to a conventional flexible printed circuit board which forms a base sheet using a polyimide or polypropylene film by laminating base sheets composed of a Teflon film having heat resistance and low dielectric constant There is an effect that a flexible printed circuit board having a dielectric constant lower than that of a printed circuit board and having a minimum dielectric loss can be manufactured.

Also, the method of manufacturing a flexible printed circuit board and the flexible printed circuit board manufactured thereby can form a base sheet with a Teflon sheet so that the flexibility of the flexible printed circuit board due to the heat (about 250 ° C) applied in the reflow process It is possible to prevent deformation and breakage and improve reliability.

In addition, the method of manufacturing a flexible printed circuit board and the flexible printed circuit board manufactured thereby have the effect of manufacturing a flexible printed circuit board having high heat resistance and low dielectric constant characteristics by constituting a base sheet with a Teflon sheet.

The method of manufacturing a flexible printed circuit board and the flexible printed circuit board manufactured thereby prevent the shape of the Teflon film from being deformed or broken during the manufacturing process by adhering the guide film to the Teflon film to form the base sheet, It is possible to prevent deterioration in production yield and reliability of the substrate.

Further, in the flexible printed circuit board manufacturing method and the flexible printed circuit board manufactured thereby, guide holes are formed in the base sheet and the adhesive sheet, the guide pins formed on the jig are arranged to pass through the guide holes formed in the base sheet and the adhesive sheet (I.e., the base sheet and the adhesive sheet) is not performed during the laminating process by stacking the base sheets and the adhesive sheet by lowering the base sheet and the adhesive sheet, thereby simplifying the manufacturing process.

Also, in the flexible printed circuit board manufacturing method and the flexible printed circuit board manufactured by this method, the guide pins formed on the jig are arranged so as to pass through the guide holes formed in the base sheet and the adhesive sheet, and then lowered to stack a plurality of base sheets and adhesive sheets Thus, the thin film patterns formed on the stacked base sheets can be aligned at precise positions, thereby reducing the production yield and reliability of the flexible printed circuit board.

1 and 2 are views for explaining a method of manufacturing a flexible printed circuit board according to an embodiment of the present invention.
Figs. 3 and 4 are diagrams for explaining the base sheet preparation step of Fig. 1; Fig.
Figs. 5 and 6 are views for explaining the steps of stacking the base sheet and the adhesive sheet of Fig. 1; Fig.
7 is a view for explaining a flexible printed circuit board according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to facilitate a person skilled in the art to easily carry out the technical idea of the present invention. . In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 and 2, a flexible printed circuit board manufacturing method includes preparing a base sheet 100 (S100), preparing an adhesive sheet 200 (S200), a laminating step S300, (S400), a via hole (300) forming step (S500), and a connecting pattern forming step (S600).

The guide film 120, the Teflon film 110 and the thin film pattern 160 are sequentially laminated in the step of preparing the base sheet 100 and the guide film 120 and the Teflon film 110 The base sheet 100 on which the guide holes are formed is prepared. At this time, the guide pin 420 of the jig 400 is inserted into the guide hole to easily perform a stacking step (S300) to be described later.

3 and 4, the step of preparing the base sheet 100 includes a step S110 of bonding the Teflon film 110 and the guide film 120, a step S130 of forming the seed layer 140, A plating layer 150 forming step S150, a thin film pattern forming step S170 and a hole forming step S190.

The Teflon film 110 having the heat resistance and the low dielectric constant is prepared in the step of sticking the Teflon film 110 and the guide film 120 (S110). That is, after the flexible printed circuit board is manufactured, the semiconductor element is mounted through the surface mounting process (i.e., the SMT process).

At this time, since the flexible printed circuit board for high frequency in development is constructed of the base sheet 100 using polypropylene having heat resistance of about 160 ° C to 180 ° C, it is necessary to perform the reflow process during the surface mounting process There is a problem that the base sheet 100 is deformed or damaged by a losing heat (about 250 deg. C).

In order to prevent the reliability of the flexible printed circuit board when the base sheet 100 is deformed or broken, in the flexible printed circuit board manufacturing method according to the embodiment of the present invention, (100).

At this time, since the Teflon film 110 is not deformed even at a temperature of about 300 DEG C, deformation and breakage of the base sheet due to heat applied in the reflow process can be prevented.

Thus, the base sheet 100 is formed by using the Teflon film 110 in the step of sticking the Teflon film 110 and the guide film 120 (S110).

Accordingly, the method of manufacturing a flexible printed circuit board and the flexible printed circuit board manufactured thereby prevent deformation and breakage of the flexible printed circuit board due to the heat (about 250 ° C) applied in the reflow process, There is an effect that can be improved.

Teflon is mainly used as a lubricant, releasing material and insulating material. Since Teflon has the best heat resistance and dielectric properties (that is, low dielectric constant) among the polymer materials, it is used as a base material for a high-frequency printed circuit board requiring low dielectric constant and heat resistance.

However, since Teflon is soft-melting and thermoplastic, the substrate is deformed due to the heat and pressure applied in the manufacturing process, and the defect rate is high. Accordingly, Teflon is mainly used as a single-sided or double-sided substrate of a thick hard type.

In the embodiment of the present invention, a thin Teflon film 110 is used as the base sheet 100 to fabricate a flexible printed circuit board. Since the Teflon film 110 is deformed or broken even at a small pressure applied during the manufacturing process due to its soft-melting property, the yield and reliability of the flexible printed circuit board are lowered.

In order to prevent deformation and breakage of the Teflon film 110 during the manufacturing process, the guide film 120 is adhered to one side of the Teflon film 110 in the step of adhesion S110 of the Teflon film 110 and the guide film 120 do.

At this time, the guide film 120 is a rigid polyethylene terephthalate (PET) film as an example.

The adhesive sheet is interposed between the Teflon film 110 and the guide film 120 to adhere the Teflon film 110 and the guide film 120 in the adhesive step S110 of the Teflon film 110 and the guide film 120. That is, since the guide film 120 must be removed in the lamination step S300 to be described later, the Teflon film 110 and the guide film 120 can be easily removed while supporting the Teflon film 110 in the adhesion step S110 And the Teflon film 110 and the guide film 120 are bonded to each other in an adhesive state (i.e., an adhesive sheet). Here, the pressure-sensitive adhesive sheet is, for example, a silicone (Si) -based pressure-sensitive adhesive.

As described above, in the flexible printed circuit board manufacturing method according to the embodiment of the present invention, the guide sheet 120 is adhered to the Teflon film 110 to form the base sheet 100, so that the shape of the Teflon film 110 It is possible to prevent deformation or breakage of the flexible printed circuit board, thereby preventing the production yield and reliability of the flexible printed circuit board from deteriorating.

The seed layer 140 is formed on one side of the Teflon film 110 in the step of forming the seed layer 140 (S130). The seed layer 140 is formed on the other surface of the Teflon film 110 (that is, the surface facing the one surface on which the guide film 120 is adhered) through the deposition process or the sputtering process in the formation step S130 ). In the seed layer 140 forming step S130, a seed layer 140 made of a mixed material of nickel copper (NiCu) and copper (Cu) or nickel copper (NiCu) is formed on the other surface of the Teflon film 110 .

In the plating layer 150 forming step S150, the plating layer 150 is formed on the seed layer 140. At this time, in the step of forming the plating layer 150 (S150), copper (Cu) is electroplated to form a plating layer 150 on the seed layer 140.

Here, the seed layer 140 and the plating layer 150 constitute a circuit pattern and are formed to have a thickness of about 5 mu m.

In the thin film pattern formation step S170, the thin film pattern 160 is formed on the other surface of the Teflon film 110. [ That is, in the thin film pattern formation step S170, the seed layer 140 formed on the other surface of the Teflon film 110 and a part of the plated layer 150 are removed through an etching process to form a thin film pattern 160 are formed.

A plurality of first guide holes 170 penetrating the Teflon film 110 and the guide film 120 are formed in the first guide hole forming step S190. That is, in the step S190 of forming the first guide hole 170, in order to align the base sheets 100 in precise positions while firmly fixing the base sheet 100 to the jig 400 in a stacking step S300 A plurality of first guide holes 170 are formed. Here, in the first guide hole forming step S190, the first guide hole 170 is formed in the base sheet 100 through a punching process, a laser drilling process, or the like.

In step S200 of preparing the adhesive sheet 200, an adhesive sheet 200 having a plurality of second guide holes 220 is prepared. At this time, in step S200 of preparing the adhesive sheet 200, a second guide hole 220 is formed at a position corresponding to the first guide hole 170 when the base sheet 100 and the adhesive sheet 200 are laminated do.

In step S200 of preparing the adhesive sheet 200, a multi-layered adhesive sheet 200 having an adhesive layer on one side or both sides of the film substrate may be prepared.

For example, the adhesive sheet 200 may be a CPP (Casted Polypropylene) film having a low dielectric loss and a low dielectric constant. At this time, the CPP film is formed as a multilayer structure in which an adhesive layer is formed on one side or both sides of a polypropylene (PP) film (hereinafter referred to as a PP film).

Here, the adhesive layer is made of the same material as the CPP film (for example, polyethylene (polyethylene terephthalate)) to increase the adhesive force between the polymer (that is, the Teflon film 110 of the base sheet 100) (E.g., polyethylene, polypropylene (PP), polyimide, etc.) and an additive (e.g., acrylate).

In step S200 of preparing the adhesive sheet 200, the adhesive sheet 200 having a single-layer structure may be prepared.

At this time, in step S200 of preparing the adhesive sheet 200, the adhesive sheet 200 formed of a composite material in which a material such as polyethylene, polypropylene, or polyimide excellent in adhesion to polymer and metal is mixed with an additive is prepared As an example.

In step S200 of preparing the adhesive sheet 200, an adhesive sheet 200 made of Teflon may be prepared.

In the lamination step (S300), a plurality of base sheets (100) and the adhesive sheet (200) are laminated. At this time, in the stacking step S300, the base sheet 100 and the adhesive sheet 200 are alternately stacked, and the adhesive sheet 200 is interposed between the base sheets 100. [

In the stacking step S300, the plurality of base sheets 100 and the adhesive sheets 200 are laminated using the jig 400. [ That is, in the stacking step S300, the thin film patterns 160 of the base sheet 100 should be laminated so as to be aligned at the correct positions, so that the reliability of the flexible printed circuit board can be provided.

Accordingly, in the stacking step S300, the plurality of base sheets 100 and the adhesive sheets 200 are laminated using the jig 400 including the guide pins 420. [

An example of the stacking step S300 in which two base sheets 100 (i.e., the first base sheet 100a and the second base sheet 100b) and the adhesive sheet 200 are laminated is described with reference to Figs. 5 and 6 Here is a description.

The laminating step S300 includes a laminating step S310 of the first base sheet 100a, a removing step S330 of removing the guide film 120a of the first base sheet 100a, a laminating step S350 of the adhesive sheet 200, 2 stacking step S370 of the base sheet 100b and a step S390 of removing the guide film 120b of the second base sheet 100b.

In the laminating step S310 of the first base sheet 100a, the first base sheet 100a is laminated on the jig 400. That is, in the laminating step S310 of the first base sheet 100a, the guide pins 420 of the jig 400 are arranged to penetrate the first guide holes 170a of the first base sheet 100a, And the first base sheet 100a is stacked on the jig 400. As shown in Fig.

In order to facilitate removal of the guide film 120a in the laminating step S310 of the first base sheet 100a, the thin film pattern 160a formed on the first base sheet 100a is positioned in the downward direction, The sheet 100a is laminated. That is, in the laminating step S310 of the first base sheet 100a, the first base sheet 100a is laminated so that the thin film pattern 160a is positioned in the downward direction, and the guide film 120a is disposed on the upper side.

The guide film 120 is removed from the first base sheet 100a stacked on the jig 400 in the step of removing the guide film 120a of the first base sheet 100a. That is, in the step S330 of removing the guide film 120 of the first base sheet 100a, the guide film 120a and the adhesive film 130a of the first base sheet 100a disposed on the upper portion are removed.

In the step of stacking the adhesive sheet 200 (S350), the adhesive sheet 200 is laminated on the jig 400. That is, in the step of stacking the adhesive sheet 200 (S350), the guide pins 420 of the jig 400 are arranged to penetrate the second guide holes 220 of the adhesive sheet 200, respectively, The sheet 200 is stacked on the jig 400. Fig. At this time, the adhesive sheet 200 is laminated on the first base sheet 100a stacked on the jig 400 in the adhesive sheet 200 stacking step S350.

In the laminating step S370 of the second base sheet 100b, the second base sheet 100b is laminated on the jig 400. [ That is, in the step of stacking the second base sheet 100b, the guide pins 420 of the jig 400 are arranged to penetrate the first guide holes 170b of the second base sheet 100b, So that the second base sheet 100b is laminated on the jig 400.

 At this time, the second base sheet 100b is laminated on the adhesive sheet 200 stacked on the jig 400 in the step of stacking the second base sheet 100b. In the second base sheet 100b stacking step S370, the second base sheet 100b is laminated such that one surface of the second base sheet 100b on which the thin film pattern 160b is formed is disposed on the adhesive sheet 200. [

The guide film 120b is removed from the second base sheet 100b stacked on the jig 400 in the step S390 of removing the guide film 120b of the second base sheet 100b. That is, in the step of removing the guide film 120b of the second base sheet 100b, the guide film 120b and the adhesive film 130b of the second base sheet 100b disposed on the upper portion are removed.

As described above, in the flexible printed circuit board manufacturing method, the guide pins 420 formed on the jig 400 in the stacking step S300 are inserted into the guide holes formed in the base sheet 100 and the adhesive sheet 200 The base sheet 100 and the adhesive sheet 200 are stacked so that the base sheet 100 and the adhesive sheet 200 are stacked so that the base sheet 100 and the second guide holes 220, The adhesive sheet 200) is not performed, so that the manufacturing process can be simplified.

In the method of manufacturing a flexible printed circuit board, a guide pin 420 formed in the jig 400 in the stacking step S300 is inserted into the guide hole formed in the base sheet 100 and the adhesive sheet 200 The base sheet 100 and the adhesive sheet 200 are stacked so as to penetrate through the first base sheet 100 and the second base sheet 100, Can be aligned at the correct positions, thereby preventing the production yield and reliability of the flexible printed circuit board from deteriorating.

In the bonding step (S400), a plurality of base sheets (100) and adhesive sheets (200) stacked on the jig (400) are adhered to each other to form a laminate.

In the bonding step S400, the plurality of base sheets 100 and the adhesive sheets 200 are preliminarily bonded by compressing them, and then the plurality of base sheets 100 and the adhesive sheets 200 are bonded together to form a laminate. .

The preliminary bonding is performed by compressing a plurality of base sheets 100 and the adhesive sheet 200 laminated on the jig 400 through a water injection molding (WIM) process in which a high water pressure is applied and compressed do.

The present bonding is an example of bonding a plurality of base sheets 100 and the adhesive sheet 200 preliminarily bonded through a hot press process applying a predetermined pressure and heat. At this time, a plurality of base sheets 100 and the adhesive sheet 200 are adhered to each other by applying a lower pressure than the pre-adhering step (i.e., the water injection molding step) in this adhesion (i.e., hot pressing step).

When the adhesive sheet 200 is formed of a Teflon material, the adhesive is pressed together with a high temperature of about 300 DEG C or higher.

In the bonding step (S400), bonding of the plurality of base sheets (100) and the adhesive sheet (200) is completed to form a laminate, and the laminate is separated from the jig (400).

In the via hole formation step S500, at least one via hole 300 penetrating the stacked body is formed. That is, in the step of forming the via hole 300 (S500), the via hole 300 is formed in the laminated body separated from the jig 400 by punching, radar drill, or the like.

1 and 2, a plurality of base sheets 100 and an adhesive sheet 200 are laminated and adhered to form a via hole 300. However, the present invention is not limited thereto, and each of the base sheets 100, And the via hole 300 may be formed in the adhesive sheet 200, followed by lamination and bonding

The connecting pattern 320 may be formed in the via hole 300 in order to electrically connect the thin film patterns 160 formed in the plurality of base sheets 100 to each other . At this time, in the connection pattern 320 formation step S600, the connection pattern 320 is formed by filling the via hole 300 with a conductive material. Here, in the connecting pattern 320 forming step S600, the connecting pattern 320 may be formed by plating a conductive material on the inner wall surface of the via hole 300 and the thin film pattern 160 exposed to the outside of the laminate .

On the other hand, the flexible printed circuit board manufacturing method may further include forming a protective layer on the upper surface of the laminated body formed by stacking the plurality of base sheets 100 and the adhesive sheets 200.

In the step of forming the protective layer, a coating solution is coated on the surface of the base substrate and the thin film pattern 160 laminated on the uppermost part of the laminate and then cured to form a thin film pattern 160 and a protective layer . At this time, the protective layer may be composed of a composite material including a resin such as polyimide, polypropylene, and polyimide.

In addition, the flexible printed circuit board manufacturing method may further include forming the electrode portion. At this time, in the step of forming the electrode part, the electrode part may be formed by removing a part of the protective layer and then plating a conductive material such as copper on the corresponding area. Here, the electrode portion may be formed on at least one of the plurality of thin film patterns 160 disposed on the upper surface of the laminate.

Referring to FIG. 7, a printed circuit board manufactured by the method of manufacturing a flexible printed circuit board according to an embodiment of the present invention includes a plurality of base sheets 100 and an adhesive sheet 200 alternately stacked, , And a circuit pattern formed on the inside and the top surface of the laminate.

The laminate is formed by alternately laminating a plurality of base sheets 100 and an adhesive sheet 200 so that the Teflon film 110 and the adhesive sheet 200 are repeatedly laminated. At this time, the adhesive sheet 200 is interposed between the Teflon films 110 in the laminate.

In this case, although the adhesive sheet 200 is shown as a single layer in FIG. 7, the adhesive sheet 200 may have a multi-layer structure.

The circuit pattern is composed of a thin film pattern 160 exposed on the upper surface of the laminate, a thin film pattern 160 interposed in the laminate, and a connection pattern 320 electrically connecting them.

That is, in the circuit pattern, the thin film pattern 160 formed on the topmost base sheet 100 is exposed on the upper surface of the laminate as the base sheets 100 are laminated, and the thin film pattern 160 are interposed inside the laminate. At this time, the thin film patterns 160 are electrically connected (that is, energized) through the connection pattern 320 formed in the via hole 300.

7, the connection pattern 320 is filled in the via hole 300. However, the connection pattern 320 may be plated on the inner wall surface of the via hole 300. FIG.

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 many variations and modifications may be made without departing from the scope of the present invention. It will be understood that the invention may be practiced.

100: Base sheet 110: Teflon film
120: Guide film 130: Adhesive film
140: Seed layer 150: Plated layer
160: thin film pattern 170: first guide hole
200: adhesive sheet 220: second guide hole
300: via hole 320: connection pattern
400: jig 420: guide pin

Claims (19)

Preparing a base sheet which is a Teflon film having a thin film pattern formed on one surface thereof;
Preparing an adhesive sheet;
Stacking a plurality of base sheets and an adhesive sheet; And
And adhering the laminate having the plurality of base sheets and the adhesive sheet laminated by heating under pressure. The method according to claim 1,
The step of preparing the base sheet may include:
Adhering a guide film to one surface of the Teflon film; And
And forming a thin film pattern on the other surface of the Teflon film. 3. The method of claim 2,
Wherein the guide film is a polyethylene terephthalate (PET) film. 3. The method of claim 2,
Wherein the step of adhering the guide film comprises interposing a silicone-based adhesive film between the Teflon film and the guide film. 3. The method of claim 2,
Wherein the step of preparing the base sheet further comprises the step of forming a plurality of first guide holes in the base sheet. 3. The method of claim 2,
Wherein the step of preparing the base sheet further comprises the step of forming at least one via hole passing through the Teflon film, the guide film and the thin film pattern. The method according to claim 1,
Wherein the step of preparing the adhesive sheet includes forming a plurality of second guide holes passing through the adhesive sheet,
Wherein the plurality of second guide holes are formed at positions corresponding to the plurality of first guide holes formed in the base sheet. The method according to claim 6,
Wherein the step of preparing the adhesive sheet comprises forming at least one via hole penetrating the adhesive sheet. The method according to claim 1,
The adhesive sheet may be a multi-layered CPP (Casted Polypropylene) film having an adhesive layer formed on at least one surface thereof,
Wherein the flexible film is an adhesive film of a single-layer structure including at least one of polyethylene, polypropylene, polyimide, and Teflon. The method according to claim 1,
Wherein the plurality of base sheets and the adhesive sheets are alternately laminated in the laminating step so that an adhesive sheet is interposed between the base sheet and the other base sheet. The method according to claim 1,
Wherein the step of stacking comprises:
Stacking a base sheet on the jig through a guide pin of the jig in the first guide hole;
Removing the guide film of the base sheet; And
And passing the guide pin of the jig through the second guide hole to stack the adhesive sheet on the top of the base sheet. The method according to claim 1,
Further comprising a step of preliminarily bonding the stacked body by applying a water pressure to the stacked body prior to the step of heating and pressing the stacked body. The method according to claim 1,
Forming a via hole through the base sheet and the adhesive sheet after the bonding step; And
And forming a connection pattern in the inside of the via hole. A laminate in which a base sheet and an adhesive sheet are alternately laminated; And
And a circuit pattern formed on the laminate,
Wherein the base sheet comprises a Teflon film. 15. The method of claim 14,
The base sheet;
Teflon film; And
And a thin film pattern formed on one surface of the Teflon film. 15. The method of claim 14,
In the circuit pattern,
A plurality of thin film patterns formed on one side of the Teflon film and disposed on the inside and the top side of the laminate; And
And a connection pattern connecting the plurality of thin film patterns. 17. The method of claim 16,
Wherein the connection pattern is formed on an inner wall surface of a via hole formed through the laminate. 17. The method of claim 16,
Wherein the connection pattern is filled in a via hole formed through the laminate. 15. The method of claim 14,
The adhesive sheet may be a multi-layered CPP (Casted Polypropylene) film having an adhesive layer formed on at least one surface thereof,
A flexible printed circuit board which is an adhesive film of a single-layer structure containing at least one of polyethylene, polypropylene and polyimide.

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