WO2018016829A1

WO2018016829A1 - Flexible circuit board and manufacturing method therefor

Info

Publication number: WO2018016829A1
Application number: PCT/KR2017/007669
Authority: WO
Inventors: 손동은; 이재문
Original assignee: 스템코 주식회사
Priority date: 2016-07-20
Filing date: 2017-07-17
Publication date: 2018-01-25
Also published as: CN109804717A; KR101915947B1; JP2021040167A; KR20180010064A; JP2019521528A; TW201804878A; TWI670997B

Abstract

A flexible circuit board and a manufacturing method therefor are provided. A flexible circuit board comprises: a base film; a plurality of first conductive patterns formed on one surface of the base film; a first protection layer formed to cover the plurality of first conductive patterns; and a first heat dissipation layer covering the first protection layer, wherein the first heat dissipation layer includes a base material and a heat dissipation material contained in the base material.

Description

Flexible circuit board and its manufacturing method

The present invention relates to a flexible circuit board and a method of manufacturing the same.

Recently, according to the trend of miniaturization in electronic devices, chip on film (COF) packaging technology using a flexible circuit board is being used. Flexible circuit boards and COF package technology using the same are used in flat panel displays (FPDs), such as liquid crystal displays (LCDs), organic light emitting diode (OLED) display devices, and the like. do.

The conductive pattern formed on the flexible circuit board connects the circuit elements and transfers electrical signals transmitted at high speed. On the other hand, with the miniaturization of electronic devices on which flexible circuit boards are mounted, high integration of flexible circuit boards and conductive patterns formed thereon has also been progressed. Due to integration and precision, problems of malfunction of circuit elements due to heat generated on conductive patterns have arisen. have.

In order to effectively dissipate heat generated from the conductive pattern, a method of increasing the thickness of the conductive pattern or attaching a metal tape made of aluminum or copper to the back surface of the base film on which the conductive pattern is formed has been introduced. However, such a method may make it difficult to realize the miniaturization of the flexible circuit board, or may require an additional process and cause problems such as an increase in production cost.

The technical problem to be solved by the present invention is to provide a flexible circuit board having good heat dissipation characteristics, including a heat dissipation layer containing a heat dissipation material on the protective layer covering the conductive pattern.

Another technical problem to be solved by the present invention is to provide a method for manufacturing a flexible circuit board on which a heat dissipation layer containing a heat dissipation material is formed on a protective layer covering the conductive pattern.

Technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to an aspect of the present disclosure, a flexible circuit board may include a base film, a plurality of first conductive patterns formed on one surface of the base film, and a plurality of first conductive patterns formed to cover the plurality of first conductive patterns. A heat dissipation layer covering the first protective layer and the first protective layer, wherein the heat dissipation layer includes a first heat dissipation layer including a base material and a heat dissipation material included in the base material.

In some embodiments of the present disclosure, the height of the top surface of the first protective layer from the base film may be equal to or higher than the height of the top surfaces of the plurality of conductive patterns from the base film.

In some embodiments of the present invention, the top surface of the first heat dissipation layer may be substantially flat.

In some embodiments of the present invention, the ratio of the thickness of the first protective layer and the first heat dissipation layer may be 2: 8 to 8: 2.

In some embodiments of the present invention, the thickness of the first protective layer is 1 μm to 30 μm, the thickness of the first heat dissipating layer is 1 μm to 30 μm, and the thickness of the first protective layer and the first heat dissipating layer. The sum may be 2 μm to 60 μm.

In some embodiments of the present invention, the base material may include the same material as the material constituting the first protective layer.

In some embodiments of the present disclosure, a plurality of second conductive patterns formed on the other surface of the base film opposite to the one surface thereof, a second protective layer formed to cover the plurality of second conductive patterns, and the second protective layer may be covered. It may further include a second heat dissipation layer including a heat dissipation material therein.

In some embodiments of the present disclosure, the first passivation layer is formed along a profile of the plurality of first conductive patterns, and an upper surface of the first passivation layer is formed on the first surface of the first conductive pattern and the first passivation layer. And a second surface between the surfaces, wherein a height of the first surface from the base film may be higher than a height of the second surface from the base film.

In some embodiments of the present disclosure, the first heat dissipation layer may be formed along a profile of the upper surface of the first protective layer.

In some embodiments of the present disclosure, the semiconductor device may further include a plating layer interposed between the first conductive pattern and the first protective layer.

According to one or more exemplary embodiments, a method of manufacturing a flexible circuit board provides a base film having a plurality of conductive patterns formed on at least one surface thereof, and forms a protective layer to cover the plurality of conductive patterns. And forming a heat dissipation layer including a heat dissipation material mixed therein on the protective layer.

In some embodiments of the present disclosure, forming the heat dissipation layer may include forming a height of the heat dissipation layer from the base film to be higher than a top surface of the conductive pattern.

According to the flexible circuit board according to the embodiments of the present invention, a heat radiation layer including a heat radiation material is formed on the base film, so that heat generated from the conductive pattern can be effectively released.

In addition, the protective layer interposed between the heat dissipation layer and the conductive pattern is formed so as to completely cover the conductive pattern, thereby preventing the electrical reliability deterioration due to the heat dissipation material included in the heat dissipation layer.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a cross-sectional view of a flexible circuit board according to an embodiment of the present invention.

FIG. 2 is an enlarged view enlarging a part of FIG. 1. FIG.

3 is a cross-sectional view of a flexible circuit board according to another embodiment of the present invention.

4 is a cross-sectional view of a flexible circuit board according to another embodiment of the present invention.

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

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. The size and relative size of the components shown in the drawings may be exaggerated for clarity of explanation. Like reference numerals refer to like elements throughout the specification, and "and / or" includes each and every combination of one or more of the mentioned items.

When elements or layers are referred to as "on" or "on" of another element or layer, intervening other elements or layers as well as intervening another layer or element in between. It includes everything. On the other hand, when a device is referred to as "directly on" or "directly on" indicates that no device or layer is intervened in the middle.

The spatially relative terms " below ", " beneath ", " lower ", " above ", " upper " It may be used to easily describe the correlation of a device or components with other devices or components. Spatially relative terms are to be understood as including terms in different directions of the device in use or operation in addition to the directions shown in the figures. For example, when flipping a device shown in the figure, a device described as "below" or "beneath" of another device may be placed "above" of another device. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can also be oriented in other directions, so that spatially relative terms can be interpreted according to orientation.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, "comprises" and / or "comprising" does not exclude the presence or addition of one or more other components in addition to the mentioned components.

Although the first, second, etc. are used to describe various elements or components, these elements or components are of course not limited by these terms. These terms are only used to distinguish one element or component from another element or component. Therefore, the first device or component mentioned below may be a second device or component within the technical idea of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in a sense that can be commonly understood by those skilled in the art. In addition, the terms defined in the commonly used dictionaries are not ideally or excessively interpreted unless they are specifically defined clearly.

1 is a cross-sectional view of a flexible circuit board according to an exemplary embodiment of the present invention, and FIG. 2 is an enlarged view of a portion of FIG. 1.

1 and 2, a flexible circuit board according to an embodiment of the present invention may include a base film 10, a first conductive pattern 20, a first protective layer 30, and a first heat dissipation layer 40. It may include.

The base film 10 may be formed of a flexible material and may be included as the substrate in the flexible circuit board 1 to allow the flexible circuit board 1 to be bent or folded. The base film 10 may be, for example, a polyimide film. Alternatively, the base film 10 may be a PET film, polyethylene naphthalate film, polycarbonate film or insulating metal foil. In the flexible circuit board 1 according to the embodiment of the present invention, the base film 10 will be described as being a polyimide film.

The first conductive pattern 20 may be formed on the base film 10. For example, the first conductive pattern 110 may have at least one strip-shaped conductive line having a predetermined width. The first conductive pattern 20 may transfer electrical signals between the circuit elements mounted on the base film 10 and the electronic devices to which the flexible circuit board 1 is connected.

The first conductive pattern 20 may include, for example, a conductive material such as copper, but the present invention is not limited thereto. Specifically, the first conductive pattern 20 may be made of a material having electrical conductivity, such as gold and aluminum.

The first passivation layer 30 may be formed to cover the first conductive pattern 20. The first protective layer 30 may include an insulating material, and the insulating material may be, for example, a solder resist. Alternatively, the first protective layer 30 may include a coverlay film.

The first passivation layer 30 may completely cover the first conductive pattern 20. That is, the level of the upper surface 35 of the first protective layer 30 may be equal to or higher than the level of the uppermost surface 25 of the first conductive pattern 20. Therefore, the height of the upper surface 35 of the first protective layer 30 from the base film 10 may be equal to or higher than the height of the uppermost surface 25 of the first conductive pattern 20 from the base film 10.

Although not shown in FIG. 1, an additional plating layer may be formed between the first conductive pattern 20 and the first protective layer 30 to cover the surface of the first conductive pattern 20. For example, the plating layer may be formed by plating a material such as copper, tin, nickel, palladium, gold, or an alloy thereof on the first conductive pattern 20.

In the flexible circuit board 1 according to the exemplary embodiment of the present invention, the upper surface 35 of the first protective layer 30 may be substantially flat. Substantially flat herein may include a case where some unevenness is formed on an upper surface of the first protective layer 30. However, in spite of the irregularities, the height difference between the uppermost part and the lowermost part of the upper surface of the first protective layer 30 can be negligible compared to the overall thickness of the first protective layer 30.

In some embodiments of the present invention, after forming the first protective layer 30 on the first conductive pattern 20 to form the first protective layer 30 having a flat top surface, the first protective layer 30 is formed. The process of planarizing the upper surface of the may be added.

The first heat dissipation layer 40 may be formed on the first protective layer 30. The first heat dissipation layer 40 may be formed to cover the top surface of the first passivation layer 30. As shown in FIG. 1, the first heat dissipation layer 40 may be formed to completely cover the surface of the first protective layer 30, but the present invention is not limited thereto. The first heat dissipation layer 40 may be formed so as to cover only an area on the first protective layer 30 overlapping the first conductive pattern 20.

As described above, since the height of the upper surface 35 of the first passivation layer 30 may be the same as or higher than the height of the top surface 25 of the first conductive pattern 20, the first passivation layer 30 may be covered. The height of the lower surface 41 of the first heat dissipation layer 40 may also be equal to or higher than the height of the uppermost surface 25 of the first conductive pattern 20.

In some embodiments of the present invention, the ratio of the thickness of the first protective layer 30 and the first heat dissipation layer 40 may be 2: 8 to 8: 2. Here, the thickness of the first protective layer 30 refers to the height from the top surface of the first conductive pattern 20 to the top surface 35 of the first protective layer 30, the thickness of the first heat dissipation layer 40 The height from the lower surface 41 of the first heat dissipation layer 40 on the upper surface 35 of the first protective layer 30 to the uppermost surface of the first heat dissipation layer 40 is referred to. When the thickness of the first heat dissipation layer 40 is too thin compared to the thickness of the first protective layer 30, the heat dissipation effect of the first conductive pattern 20 by the first heat dissipation layer 40 may be insufficient. have. On the other hand, when the thickness of the first protective layer 30 is too thin compared to the first heat dissipation layer 40, there is a fear that the insulating property is lowered, compared to the thickness of the first protective layer 30, the first heat dissipation layer When the thickness of 40 is formed more than necessary, the manufacturing cost of the flexible circuit board 1 may be excessively increased compared with the increase in the heat radiation effect.

In some embodiments of the present invention, the thickness of the first protective layer 30 may be 1 μm to 30 μm, the thickness of the first heat dissipation layer 40 may be 1 μm to 30 μm, and the first protective layer 30 may be used. ) And the thickness of the first heat dissipation layer 40 may be 2 μm to 60 μm.

The first heat dissipation layer 40 may include a base material and a heat dissipation member 45. The base material may include, for example, a solder resist or coverlay film. In some embodiments of the present invention, the base material of the first heat dissipation layer 40 may include the same material as the first protective layer 30.

The heat dissipation member 45 as the heat dissipation material included in the first heat dissipation layer 40 may include a material having good thermal conductivity, and for example, a metallic material such as aluminum or copper or a carbon material such as graphene or carbon nanotubes. It may include or may contain a compound thereof.

In some embodiments of the present invention, the heat dissipation member 45 may include a spherical heat dissipation ball, but the present invention is not limited thereto. The heat dissipation member 45 may have a polyhedron shape such as a hexahedron, and may be mixed with the base material of the first heat dissipation layer 40 so as to transfer heat generated in the first conductive pattern 20 to the air without limitation in shape. It can be applied to the invention.

In the flexible circuit board 1 according to an embodiment of the present invention, the heat generated from the first conductive pattern 20 is discharged to the outside by the heat radiating material 45 included in the first heat radiating layer 40. I can promote it. Therefore, the circuit element and the electronic device mounted on the first conductive pattern 20 by the first heat dissipation layer 40 reduce the influence of heat received from the heat generated in the first conductive pattern 20, and the flexible circuit board 1 Operating reliability) may be increased.

In addition, forming the first heat dissipation layer 40 on the first protective layer 30 in this way may be advantageous in terms of production process and production cost rather than forming a separate metal tape on the back surface of the base film 10. Can be.

Meanwhile, in the flexible circuit board 1 according to the exemplary embodiment, the first heat dissipation layer 40 may be spaced apart from the first conductive pattern 20 due to the first protective layer 30. In addition, since the height of the upper surface 35 of the first protective layer 30 is equal to or higher than the height of the uppermost surface of the first conductive pattern 25, the first heat dissipation between the plurality of first conductive patterns 20. The heat dissipation member 45 included in the layer 40 and the first heat dissipation layer 40 is not located.

When the first heat dissipation layer 40 containing the heat dissipation member 45 is interposed between the first conductive patterns 20 on the base film 10, the heat dissipation member 45 reacts with moisture, and the like. Due to the leakage current formed to flow between the patterns 20, the insulation effect between the plurality of first conductive patterns 20 may be reduced. Therefore, the operation reliability of the flexible circuit board 1 can also be lowered.

However, the first heat dissipation layer 40 of the flexible circuit board 1 according to the exemplary embodiment of the present invention may include the first heat dissipation layer 40 and the first heat dissipation layer 40 between the plurality of first conductive patterns 20. Since the heat dissipation member 45 included in the 40 is not positioned, even when the heat dissipation member 45 in the first heat dissipation layer 40 reacts with moisture, a leakage current is generated between the first conductive patterns 20. Can be prevented and effectively insulated between the first conductive patterns 20.

3 is a cross-sectional view of a flexible circuit board according to another embodiment of the present invention. Hereinafter, the description of the parts in common with the above-described embodiments will be omitted and the differences will be mainly described.

Referring to FIG. 3, the flexible circuit board 2 according to another embodiment of the present invention differs in shape of the flexible circuit board and the first protective layer 130 and the first heat dissipation layer 140 in the above-described embodiment. Can be.

The upper surface 135 of the first protective layer 130 may be formed along the profile of the upper surface of the first conductive pattern 20. That is, the upper surface 135 of the first protective layer 130 includes a first surface 136 on the first conductive pattern 20 and a second surface 137 between the first surface 136, the base The height of the first face 136 from the film 10 is higher than the height of the second face 137.

Meanwhile, although the top surface 135 of the first passivation layer 130 is formed along the profile of the top surface of the first conductive pattern 20, it may still be equal to or higher than the height of the top surface of the first conductive pattern 20. have. That is, the level of the second surface 137 that is lower than the height of the first surface 136 of the upper surface 135 of the first protective layer 130 is still equal to or higher than the level of the uppermost surface of the first conductive pattern 20. The heat dissipation material included in the first heat dissipation layer 140 and the first heat dissipation layer 40 may be prevented from being disposed between the first conductive patterns 20. Therefore, despite the shape of the upper surface 135 of the deformed first passivation layer 130, the insulation effect between the first passivation layer 130 and the first conductive pattern 20 due to the first heat dissipation layer 140 remains the same. Can be maintained.

As the first passivation layer 130 is formed along the profile of the top surface of the first conductive pattern 20, the shape of the first heat dissipation layer 140 covering the first passivation layer 130 is also defined by the first passivation layer 130. It can be formed along the profile of). Accordingly, the upper surface of the first heat dissipation layer 140 may include a first surface 141 on the first conductive pattern 20 and a second surface 142 between the first surface, and the first surface 141. The height of may be higher than the height of the second surface 142.

Meanwhile, as in the case of the above-described embodiment, the height of the bottom surface of the first heat dissipation layer 140 may be equal to or higher than the height of the top surface of the first conductive pattern 20.

In the flexible circuit board 2 according to the present exemplary embodiment, since the first protective layer 130 is formed along the profile of the surface of the first conductive pattern 20, the upper surface 135 of the curved first protective layer 130 is formed. ), The surface area of the top surface 135 of the first protective layer 130 may increase. In addition, the contact area between the first passivation layer 130 and the first heat dissipation layer 140 may also increase due to the increased surface area of the upper surface 135 of the first passivation layer 130. Therefore, the heat transfer efficiency of the first conductive pattern 20 transferred to the first heat dissipation layer 140 through the first protective layer 130 may increase.

Meanwhile, when the first passivation layer 130 is formed along the profile of the first conductive pattern 20, after forming the first passivation layer 130, planarizing the top surface of the first passivation layer 130. This may not be done.

Referring to FIG. 4, the flexible circuit board 3 according to another exemplary embodiment may include a second conductive pattern 120 and a second conductive pattern 120 formed on a surface opposite to the first conductive pattern 20 of the base film 10. The via layer 51 may further include a via 51 penetrating the protective layer 230, the second heat dissipating layer 240, and the base film 10.

The second conductive pattern 120 may be formed on an opposite surface of one surface on which the first conductive pattern 20 of the base film 10 is formed. Like the first conductive pattern 20, the second conductive pattern 120 may include at least one or more conductive wires having a predetermined width.

The second conductive pattern 120 may be electrically connected to the first conductive pattern 20 through the via 51 penetrating the substrate. The via 51 may fill the via hole 50 formed through the base film 10. Like the first and second conductive patterns 120, the via 51 may include a conductive material such as copper or gold, or an alloy thereof. Although not shown in FIG. 4, one or more additional metal layers may be included between the inner wall of the via hole 50 and the via 51.

4 illustrates that the first conductive pattern 20 and the second conductive pattern 120 are formed at positions corresponding to the base film 10, but the present invention is not limited thereto. It will be apparent to those skilled in the art that the arrangement of the first and second conductive patterns 20 may vary according to the design of the flexible circuit board 1 and the arrangement of the circuit elements mounted thereon. .

The second protective layer 230 may be formed to cover the second conductive pattern 120. Like the first passivation layer 30, the second passivation layer 230 may be formed to completely cover the second conductive pattern 120. Therefore, the height of the upper surface of the second protective layer 230 from the other surface of the base film 10 may be equal to or higher than the height of the uppermost surface of the second conductive pattern 120.

The second heat dissipation layer 240 may be formed on the second protective layer 230. The second heat dissipation layer 240 may include a base material which is an insulating material and a heat dissipation material contained in the base material. The first heat dissipation layer 40 and the second heat dissipation layer 240 may include the same material. That is, the base material and the heat dissipation layer constituting the first heat dissipation layer 40 and the second heat dissipation layer 240 may include the same material.

As shown in FIG. 4, the second heat dissipation layer 240 may be formed to completely cover the second protective layer 230. In contrast, the second heat dissipation layer 240 may include the second conductive pattern 120. It may be formed to cover only the upper surface of the second protective layer 230 on the formed region.

As the upper surface of the second protective layer 230 is formed to be equal to or higher than the level of the upper surface of the second conductive pattern 120, the second heat dissipation layer 240 is not interposed between the second conductive patterns 120. This is the same as the description associated with the first heat dissipation layer 40. Therefore, the shape of the second heat dissipation layer 240 helps to release heat generated in the second conductive pattern 120 into the air, and at the same time, a leakage current is generated between the second conductive pattern 120 and the heat dissipating material, thereby providing a flexible circuit. It is possible to prevent reducing the operating reliability of the substrate 3.

5 and 1, a method of manufacturing a flexible circuit board according to an embodiment of the present disclosure provides a base film having a plurality of conductive patterns formed on at least one surface thereof (S10), and forming the plurality of conductive patterns. A first protective layer is formed to cover (S20), and a heat radiation layer having a heat dissipating material formed therein is formed on the first protective layer (S30).

The first conductive pattern 20 may be formed by, for example, a semi additive process of forming a resist on the base film 10 and performing plating in an electrolytic or non-electrolytic manner. A conductive layer may be formed on the layer 10 and may be formed by an etching process of etching the conductive layer.

Forming the first protective layer 30 to cover the plurality of first conductive patterns 20 may include forming a solder resist or coverlay film on the first conductive pattern 20 by printing or laminating. Can be. The first protective layer 30 needs to be sufficiently formed so that the level of the upper surface of the first protective layer 30 can be higher than the level of the uppermost surface of the first conductive pattern 20.

Here, in order to maintain the level of the upper surface of the first protective layer 30 substantially flat, a process of forming the first protective layer 30 and then flattening the upper surface may be added. Flattening the upper surface of the first protective layer 30 may include, for example, pressing the upper surface of the first protective layer 30 with a press.

Forming the first heat dissipation layer 40 to cover the first passivation layer 30 may include printing or laminating a solder resist or coverlay film including the heat dissipation material 45 on the first passivation layer 30. It may include forming into.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments but may be manufactured in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims

Base film;

A plurality of first conductive patterns formed on one surface of the base film;

A first protective layer formed to cover the plurality of first conductive patterns; And

A heat dissipation layer covering the first protective layer, wherein the heat dissipation layer includes a first heat dissipation layer including a base material and a heat dissipation material included in the base material.
The method of claim 1,

And a height of a top surface of the first protective layer from the base film is equal to or higher than a height of a top surface of the plurality of first conductive patterns from the base film.
The method of claim 1,

And a top surface of the first heat dissipation layer is substantially flat.
The method of claim 1,

The ratio of the thickness of a said 1st protective layer and a said 1st heat radiation layer is a flexible circuit board of 2: 8-8: 2.
The method of claim 1,

The thickness of the first protective layer is 1 ㎛ to 30 ㎛,

The thickness of the first heat dissipation layer is 1 ㎛ to 30 ㎛,

The sum of the thicknesses of the first protective layer and the first heat dissipation layer is 2 μm to 60 μm.
The method of claim 1,

And the base material includes the same material as the material constituting the first protective layer.
The method of claim 1,

A plurality of second conductive patterns formed on the other surface opposite to the one surface of the base film;

A second protective layer formed to cover the plurality of second conductive patterns; And

And a second heat dissipation layer covering the second protective layer and including a heat dissipation material therein.
The method of claim 1,

The first protective layer is formed along the profile of the plurality of first conductive patterns,

An upper surface of the first protective layer includes a first surface on the first conductive pattern and a second surface between the first surface,

The height of the first surface from the base film is higher than the height of the second surface from the base film.
The method of claim 8,

The first heat dissipation layer is formed along the profile of the upper surface of the first protective layer.
The method of claim 1,

The flexible circuit board further comprises a plating layer interposed between the first conductive pattern and the first protective layer.
Providing a base film having a plurality of conductive patterns formed on at least one surface thereof,

A protective layer is formed to cover the plurality of conductive patterns,

On the protective layer, including forming a heat dissipation layer including a heat dissipating material mixed therein,

The height of the said protective layer from the said base film is a manufacturing method of the flexible circuit board higher than the height of the uppermost surface of the said some conductive pattern from the said base film.
The method of claim 11,

Forming the heat dissipation layer includes forming a height of the heat dissipation layer higher than the uppermost surface of the conductive pattern from the base film.