JP2015005717A - Rigid-flexible printed circuit board and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rigid-flexible printed circuit board which reduces a burden of lamination, simplifies a manufacturing process and realizes a low unit manufacturing cost.SOLUTION: A rigid-flexible printed circuit board has at least two or more base substrates laminated with circuit layers formed on opposite surfaces, and includes: a rigid region in which a rigid insulator layer is laminated on each of the opposite surfaces of the base substrates; and a flexible region in which a coverlay is laminated on each of the opposite surfaces of the base substrates on which the rigid insulator layers are not laminated. A surface roughness is formed on one surface of coverlays laminated to be adjacent to each other among the coverlays.

Description

  The present invention relates to a hard and soft printed circuit board and a method for manufacturing the same, and more particularly to a hard and soft printed circuit board in which a base substrate is laminated in multiple layers and a method for manufacturing the same.

  Generally, a printed circuit board (PCB) is a circuit board that serves to electrically connect or mechanically fix predetermined electronic components, and is formed of an insulating material such as a phenol resin or an epoxy resin. And a copper foil layer attached to the insulating layer to form a predetermined wiring pattern.

  The printed circuit board includes a single-sided printed circuit board (Single PCB) in which a wiring pattern is formed on only one surface of an insulating layer, a double-sided printed circuit board (Double PCB) in which wiring patterns are formed on both sides of the insulating layer, and A large number of insulating layers on which wiring patterns are formed are stacked and classified into a multilayer printed circuit board (Multilayer PCB) in which wiring patterns are formed in multiple layers.

  Recently, with the downsizing, thinning, and high density of electronic products, multilayer printed circuit boards, especially flexible flexible printed circuit boards (RFPCBs) that have both flexibility, are in the market. ing .

  Such a hard and soft printed circuit board is a technology that combines existing multilayer printed circuit board technology and flexible printed circuit board technology, and is currently capable of wiring in a three-dimensional structure, is easy to assemble, Widely used in devices that require the design of highly integrated circuits such as personal computers, digital cameras, camcorders, and mobile communication terminals. Multi-layer printed circuit boards and flexible printed circuit boards have problems such as lack of space, connection reliability and component mounting due to the use of separate connectors, but hard and flexible printed circuit boards improve these problems. Therefore, the function of the component room manager board and the function of the interface can be performed simultaneously.

  The structure of the hard and flexible printed circuit board is composed of a flexible region in which a circuit pattern is formed on a flexible film such as polyester or polyimide having flexibility, and an insulating layer laminated on the flexible film. And a hard region with increased hardness.

  In such a hard and soft printed circuit board, a hard insulating layer is selectively laminated on a double-sided soft copper clad laminate having a copper foil formed on both sides, and the portion where the hard insulating layer is laminated is as follows. It is manufactured by forming a circuit pattern on the flexible film and the rigid insulating layer so that the portion which becomes the hard substrate portion and is not laminated with the hard insulating layer becomes the soft substrate portion.

Korean Patent Laid-Open No. 10-2010-0079336 Korean Unexamined Patent Publication No. 10-2011-0045991

  However, the conventional hard and soft printed circuit board has a circuit pattern formed on both sides of a soft copper foil laminate, then a process of laminating a coverlay coating and an insulating layer, and a single-sided soft copper foil in which a copper foil is formed on one side The printed circuit board was manufactured by repeating the steps of laminating the laminate and forming the circuit pattern, but due to the repetition of the lamination step and the circuit pattern formation step, a laminating load was excessively generated, There is a problem that lead time and manufacturing cost increase.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a flexible printed circuit board having a reduced lamination load, a simplified manufacturing process, and a low manufacturing cost.

  Another object of the present invention is to prevent adhesion between the surfaces of the cover lays provided so as to be laminated and in contact with each other.

  In order to solve the above-described object, a hard and flexible printed circuit board according to an embodiment of the present invention includes at least two base boards each having a circuit layer formed on both sides, and each of the base boards has a hard insulating layer on each side. And a soft region in which a cover lay is laminated on both sides of the base substrate on which the hard insulating layer is not laminated, and a surface on one surface of the cover lay laminated so as to be in contact with each other in the cover lay Roughness is formed.

  The coverlay laminated so as to be in contact with each other in the coverlay includes an inorganic filler.

  The hard and soft printed circuit board according to the present invention further includes a surface roughness layer provided between coverlays stacked in contact with each other in the coverlay.

  The surface roughness layer is formed in a film form.

  The surface roughness layer includes an inorganic filler.

  According to another aspect of the present invention, there is provided a method for manufacturing a flexible printed circuit board, comprising: preparing at least two base substrates having circuit layers formed on both sides; The method includes the steps of: laminating a cover lay on each soft region, laminating a hard insulating layer on the hard region, laminating the base substrate, and pressurizing the laminated base substrate.

  After pressing the laminated base substrate, an outer circuit layer is formed on the outermost hard insulating layer in the laminated base substrate.

  A surface roughness is formed on one surface of the coverlay that is laminated so as to be in contact with each other in the coverlay.

  In addition, the cover lay that is laminated so as to be in contact with each other in the cover lay includes an inorganic filler.

  Also, in the method for manufacturing a hard and soft printed circuit board according to the present invention, after the step of preparing the base substrate, a step of interposing a surface roughness layer between coverlays stacked so as to contact each other in the coverlay. Further included.

  The surface roughness layer includes an inorganic filler.

  As described above, according to the hard and flexible printed circuit board and the manufacturing method thereof according to the present invention, the manufacturing process is simplified by laminating the base substrate having the circuit layer formed on both sides, thereby simplifying the manufacturing process. The effect is that the time can be shortened and the manufacturing unit price can be reduced.

  In addition, the coverlay laminated on the soft region of the hard and flexible printed circuit board contains an inorganic filler to form a surface roughness on the surface of the coverlay, thereby joining the coverlays laminated so as to contact each other. This can prevent the occurrence of breakage in the soft region when the hard and flexible printed circuit board is bent.

1 is a cross-sectional view showing a hard and soft printed circuit board according to a first embodiment of the present invention. 1 is a cross-sectional view showing a hard and soft printed circuit board according to a first embodiment of the present invention. It is a photograph which shows the surface of the coverlay by the 1st Embodiment of this invention. FIG. 6 is a cross-sectional view showing a hard and soft printed circuit board according to a second embodiment of the present invention. It is sectional drawing which shows the manufacturing method of the hard flexible printed circuit board by the 1st Embodiment of this invention. It is sectional drawing which shows the manufacturing method of the hard flexible printed circuit board by the 1st Embodiment of this invention. It is sectional drawing which shows the manufacturing method of the hard flexible printed circuit board by the 1st Embodiment of this invention. It is sectional drawing which shows the manufacturing method of the hard flexible printed circuit board by the 1st Embodiment of this invention. It is sectional drawing which shows the manufacturing method of the hard flexible printed circuit board by the 1st Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Each embodiment shown below is given as an example so that those skilled in the art can sufficiently communicate the idea of the present invention. Therefore, the present invention is not limited to the embodiments described below, but can be embodied in other forms. In the drawings, the size and thickness of the device can be exaggerated for convenience. Like reference numerals refer to like elements throughout the specification.

  The terminology used herein is for the purpose of describing embodiments and is not intended to limit the invention. In this specification, the singular includes the plural unless specifically stated otherwise. As used herein, “includes” a stated component, step, action, and / or element does not exclude the presence or addition of one or more other components, steps, actions, and / or elements. Want to be understood.

  1 and 2 are cross-sectional views showing a hard and soft printed circuit board according to a first embodiment of the present invention.

  As shown in FIG. 1, the hard and flexible printed circuit board according to the first embodiment of the present invention includes a hard region R and a soft region F, and circuit layers 112, 122, and 132 are formed on both surfaces, respectively. Two or more base substrates 110, 120, and 130 are laminated, and the outer circuit layer 140 is formed outside the laminated base substrates 110, 120, and 130.

  The hard and flexible printed circuit board according to the present invention includes a first base substrate 110, a second base substrate 120, a first circuit layer 112, a second circuit layer 122, and a third circuit layer 132, respectively. 3 base substrates 130 and two outer circuit layers 140 are stacked to form 8 layers.

  The hard region R and the soft region F are regions that are not apparently divided but are arbitrarily designed in manufacturing.

  The region where the first hard insulating layer 113, the second hard insulating layer 123, and the third hard insulating layer 133 are stacked is the hard region R, and the first cover lay 114, the second cover lay 124, and the third The area where the coverlay 134 is laminated is the soft area F.

  The first base substrate 110, the second base substrate 120, and the third base substrate 130 are copper foil layers on both sides of the first flexible film 111, the second flexible film 121, and the third flexible film 131, respectively. Is a flexible copper clad laminate (Flexible Copper Clad Laminate).

  The first flexible film 111, the second flexible film 121, and the third flexible film 131 are formed of a resin material having a soft characteristic. For example, a polyimide resin system such as a polyimide resin, a polyether imide resin, or a polyamide imide resin, a polyamide resin system, or a polyester resin system may be used, and a polyimide resin system is particularly preferable. In addition, the copper foil layers formed on both surfaces of the flexible film are patterned by exposure, development, and etching processes to form a first circuit layer 112, a second circuit layer 122, and a third circuit layer 132. .

  The first base substrate 110, the second base substrate 120, and the third base substrate 130 are first on both surfaces of the first flexible film 111, the second flexible film 121, and the third flexible film 131, respectively. The first hard insulating layer 113, the second hard insulating layer 123, and the third hard insulating layer in the hard region R so that the circuit layer 112, the second circuit layer 122, and the third circuit layer 132 are protected. 133 is laminated, and the first cover lay 114, the second cover lay 124, and the third cover lay 134 are laminated in the soft region F. The first cover lay 114, the second cover lay 124, and the third cover lay 134 are made of polyimide.

  On the other hand, the first base substrate 110, the second base substrate 120, and the third base substrate 130 are stacked to form the first cover lay 114, the second cover lay 124, and the third cover lay. The part which mutually contacts between 134 will generate | occur | produce.

  Surfaces that are in contact with each other between the first cover lay 114, the second cover lay 124, and the third cover lay 134 are formed with surface roughness, and the first cover lay 114, the second cover lay 124, Bonding between the third coverlays 134 can be prevented. The first cover lay 114, the second cover lay 124, and the third cover lay 134 in which the surface roughness is formed may contain an inorganic filler, and the inorganic filler is aggregated on the surface. Thus, surface roughness is formed on the surfaces of the first cover lay 114, the second cover lay 124, and the third cover lay 134 that are in contact with each other.

  The inorganic filler is carbon and the inorganic filler is included at a content of 9.87% to form a suitable surface roughness.

  In particular, the inorganic filler is included in only one of the first cover lay 114, the second cover lay 124, and the third cover lay 134 that are in contact with each other in order to reduce the lead time and the cost. It is desirable that The inorganic filler is included only in the second cover lay 124 of the second base substrate 120, so that the upper and lower surfaces of the second cover lay 124 in contact with the first cover lay 114 and the third cover lay 134. Thus, the first cover lay 114, the second cover lay 124, and the third cover lay 134 can be prevented from being joined to each other.

  As shown in FIG. 2, the first coverlay 114 formed on the lower surface of the first flexible film 111 of the first base substrate 110 and the upper portion of the third flexible film 131 of the third base substrate 130. Only the formed third coverlay 134 contains the inorganic filler. That is, the third cover layer 114 formed on the lower surface of the first flexible film 111 in contact with the second cover layer 124 of the second base substrate 120 and the third flexible film 131 formed on the upper surface of the third flexible film 131. Since the inorganic filler is included only in the cover lay 134, the surface roughness is formed, and the first cover lay 114, the second cover lay 124, and the third cover lay 134 are joined to each other. Can be prevented.

  Meanwhile, as shown in FIGS. 3 a and 3 b, it is formed on the surface of the cover lay 124 or the surface of the first cover lay 114 formed on the lower surface of the first flexible film 111 and the upper portion of the third flexible film 131. Carbon is agglomerated with the surface of the third coverlay 134 thus formed to form a surface roughness. In order to effectively prevent the bonding between the first cover lay 114, the second cover lay 124, and the third cover lay 134, the carbon aggregated on the surface preferably has a size of 150 nm to 500 nm. .

  That is, an inorganic filler is applied to the first cover lay 114 formed on the lower surface of the cover lay 124 or the first flexible film 111 and the third cover lay 134 formed on the upper portion of the third flexible film 131. By being included, surface roughness is formed on the surface, so that an air gap can be formed between the first cover lay 114, the second cover lay 124 and the third cover lay 134 which are in contact with each other.

  Therefore, conventionally, there is a problem that if the soft region F is bent by joining the first cover lay 114, the second cover lay 124, and the third cover lay 134, the soft region is damaged. In the present invention, the first cover lay 114, the second cover lay 124, and the third cover lay 134 are prevented from being joined, and the first cover lay 114, the second cover lay 124, and the third cover lay 134 are prevented. By forming an air gap between the coverlays 134, it is possible to prevent breakage when the flexible region F is bent.

  An outer circuit layer 140 is formed outside the first base substrate 110, the second base substrate 120, and the third base substrate 130.

  The outer circuit layer 140 is formed on an upper portion of the hard insulating layer 113 of the first base substrate 110 and a lower portion of the hard insulating layer 133 of the third base substrate 130. A copper foil layer is formed on the upper portion of the hard insulating layer 113 of the first base substrate 110 and the lower portion of the hard insulating layer 133 of the third base substrate 130 by casting, laminating, sputtering, or the like. Alternatively, the outer circuit layer 140 may be formed by patterning the copper foil layer. In addition, a via that electrically connects the outer circuit layer 140 and the circuit layer 112 of the first base substrate 110 or the outer circuit layer 140 and the circuit layer 132 of the third base substrate 130 may be formed.

  FIG. 4 is a cross-sectional view illustrating a hard and soft printed circuit board according to a second embodiment of the present invention.

  As shown in FIG. 4, the hard and soft printed circuit board according to the second embodiment of the present invention includes a hard region R and a soft region F, and a first circuit layer 112 and a second circuit layer are formed on both surfaces. 122, the third circuit layer 132, the first coverlay 114, the second coverlay 124, the third coverlay 134, the first hard insulating layer 113, the second hard insulating layer 123, and the third The first base substrate 110, the second base substrate 120, and the third base substrate 130 on which the hard insulating layer 133 is formed are stacked and formed outside the first base substrate 110 and the third base substrate 130. The outer circuit layer 140 is configured.

  The other constituent elements are the same as those of the hard and flexible printed circuit board according to the first embodiment described above, and different parts from those of the hard and flexible printed circuit board according to the first embodiment will be described below.

  The hard and soft printed circuit board according to the second embodiment of the present invention further includes a surface roughness layer 150 interposed between the first cover lay 114, the second cover lay 124, and the third cover lay 134.

  The surface roughness layer 150 includes an inorganic filler, and the surface roughness of the surface roughness layer 150 is formed by aggregating the inorganic filler on the surface.

  In addition, the surface roughness layer 150 is formed in a film form in order to efficiently perform the manufacturing process.

  That is, the surface roughness layer 150 is formed between the cover lay 114 of the first base substrate 110 and the cover lay 124 of the second base substrate 120 and between the cover lay 124 of the second base substrate 120 and the third base. By interposing between the substrate 130 and the cover lay 134, an air gap is formed between the first cover lay 114, the second cover lay 124 and the third cover lay 134 which are stacked so as to be in contact with each other. In addition, it is possible to prevent the soft region F from being damaged when the first cover lay 114, the second cover lay 124, and the third cover lay 134 are joined.

  5a to 5e are cross-sectional views illustrating a method for manufacturing a hard and soft printed circuit board according to the first embodiment of the present invention.

  As shown in FIG. 5a, the flexible printed circuit board according to the first embodiment of the present invention includes at least a first circuit layer 112, a second circuit layer 122, and a third circuit layer 132 formed on both sides. Two or more base substrates 110, 120, and 130 are prepared.

  The base substrates 110, 120, and 130 are divided into a first base substrate 110, a second base substrate 120, and a third base substrate 130.

  First, a flexible copper foil laminate in which a copper foil layer is formed on each side of each of the first flexible film 111, the second flexible film 121, and the third flexible film 131 is prepared, and the first flexible film 111 is prepared. The copper foil layers formed on both surfaces of the second flexible film 121 and the third flexible film 131 are patterned by exposure, development, and etching processes, and the first circuit layer 112, the second circuit layer 122, and the third circuit layer are patterned. The circuit layer 132 is formed.

  Next, as shown in FIG. 5b, the first circuit layer 112 and the second circuit layer formed on both surfaces of the first flexible film 111, the second flexible film 121, and the third flexible film 131, respectively. In order to protect 122 and the third circuit layer 132, the first hard insulating layer 113, the second hard insulating layer 123, and the third hard insulating layer 133 are stacked in the hard region R, and the soft region F is stacked. The first cover lay 114, the second cover lay 124, and the third cover lay 134 are stacked to manufacture the first base substrate 110, the second base substrate 120, and the third base substrate 130.

  The second base substrate 120 is stacked between the first base substrate 110 and the third base substrate 130 in a subsequent process, and each of the first cover lay 114, the second cover lay 124, and the third base lay The coverlays 134 come into contact with each other.

  Therefore, in order to prevent the first cover lay 114, the second cover lay 124, and the third cover lay 134 from being joined, the cover lay 124 of the second base substrate 120 is made of an inorganic filler. The surface roughness of the cover lay 124 of the second base substrate 120 can be formed by allowing the inorganic filler to be aggregated on the surface. Therefore, it is possible to prevent the first cover lay 114, the second cover lay 124, and the third cover lay 134 from being joined.

  Next, as shown in FIG. 5c, the first base substrate 110, the second base substrate 120, and the third base substrate 130 can be stacked.

  Next, as shown in FIG. 5d, the stacked first base substrate 110, second base substrate 120, and third base substrate 130 are pressurized.

  Next, as shown in FIG. 5 e, an outer circuit layer 140 is formed on the first base substrate 110 and the third base substrate 130.

  Forming a copper foil layer on the upper portion of the first hard insulating layer 113 of the first base substrate 110 and the lower portion of the third hard insulating layer 133 of the third base substrate 130 by casting, laminating, sputtering, etc .; The outer circuit layer 140 is formed by patterning the copper foil layer.

  Also, a beer for electrically connecting the outer circuit layer 140 and the first circuit layer 112 of the first base substrate 110 or the outer circuit layer 140 and the third circuit layer 132 of the third base substrate 130 is formed. .

  That is, the hard and flexible printed circuit board according to the first embodiment of the present invention includes the first base board 110, the second base board 120, and the third base board in which the circuit layers 112, 122, and 132 are formed on both sides. After laminating 130, pressurizing only once to manufacture a hard and soft printed circuit board can reduce the laminating load due to conventional repeated lamination. Further, since the manufacturing process can be simplified, the lead time can be shortened and the manufacturing unit cost can be reduced.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

110 First base substrate
120 Second base substrate 130 Third base substrate
111, 121, 131 Flexible film 112, 122, 132 Circuit layer
113, 123, 133 Hard insulating layer 114, 124, 134 Coverlay
140 outer circuit layer 150 surface roughness layer

Claims (11)

At least two base substrates having circuit layers formed on both sides are laminated,
A hard region in which a hard insulating layer is laminated on each side of the base substrate;
A soft region in which coverlays are laminated on both sides of a base substrate on which the hard insulating layer is not laminated,
A hard and soft printed circuit board in which surface roughness is formed on one surface of a cover lay laminated to be in contact with each other in the cover lay.   The hard and soft printed circuit board according to claim 1, wherein an inorganic filler is contained in the coverlay laminated so as to be in contact with each other in the coverlay.   The hard and soft printed circuit board according to claim 1, further comprising a surface roughness layer provided between coverlays stacked so as to be in contact with each other in the coverlay.   The hard and soft printed circuit board according to claim 3, wherein the surface roughness layer is formed in a film form.   The hard and soft printed circuit board according to claim 3, wherein the surface roughness layer includes an inorganic filler. Providing at least two base substrates having circuit layers formed on both sides; and
Laminating a cover lay on the soft region of the base substrate and laminating a hard insulating layer on the hard region;
Laminating the base substrate;
Pressurizing the laminated base substrate. A method for manufacturing a hard and soft printed circuit board. After pressurizing the laminated base substrate,
The method of manufacturing a hard and soft printed circuit board according to claim 6, comprising forming an outer circuit layer on an outermost hard insulating layer in the laminated base substrate.   The method of manufacturing a hard and soft printed circuit board according to claim 6, wherein a surface roughness is formed on one surface of the cover lay laminated so as to be in contact with each other in the cover lay.   The manufacturing method of the hard and flexible printed circuit board of Claim 6 which contains an inorganic filler in the coverlay laminated | stacked so that it may mutually contact in the said coverlay. After the step of preparing the base substrate,
The method of manufacturing a hard and soft printed circuit board according to claim 6, further comprising a step of interposing a surface roughness layer between coverlays laminated so as to be in contact with each other in the coverlay.   The method for manufacturing a hard and soft printed circuit board according to claim 10, wherein the surface roughness layer includes an inorganic filler.

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