KR20140119517A - Method of manufacturing a printed circuit board - Google Patents

Method of manufacturing a printed circuit board Download PDF

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Publication number
KR20140119517A
KR20140119517A KR1020130035302A KR20130035302A KR20140119517A KR 20140119517 A KR20140119517 A KR 20140119517A KR 1020130035302 A KR1020130035302 A KR 1020130035302A KR 20130035302 A KR20130035302 A KR 20130035302A KR 20140119517 A KR20140119517 A KR 20140119517A
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KR
South Korea
Prior art keywords
heat
release film
hole
printed circuit
circuit board
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KR1020130035302A
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Korean (ko)
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이형도
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대덕전자 주식회사
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Priority to KR1020130035302A priority Critical patent/KR20140119517A/en
Publication of KR20140119517A publication Critical patent/KR20140119517A/en

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0201—Thermal arrangements, e.g. for cooling, heating or preventing overheating
    • H05K1/0203—Cooling of mounted components
    • H05K1/0204—Cooling of mounted components using means for thermal conduction connection in the thickness direction of the substrate
    • H05K1/0206—Cooling of mounted components using means for thermal conduction connection in the thickness direction of the substrate by printed thermal vias
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/0011—Working of insulating substrates or insulating layers
    • H05K3/0044—Mechanical working of the substrate, e.g. drilling or punching
    • H05K3/0047—Drilling of holes
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/46—Manufacturing multilayer circuits
    • H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
    • H05K3/4626—Manufacturing multilayer circuits by laminating two or more circuit boards characterised by the insulating layers or materials
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/46—Manufacturing multilayer circuits
    • H05K3/4697—Manufacturing multilayer circuits having cavities, e.g. for mounting components

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Structure Of Printed Boards (AREA)

Abstract

The present invention relates to a method to process a heat discharge hole of a printed circuit board. Provided is the method which includes the steps of: (a) punching a heat discharge hole on a substrate; (b) attaching a release film on one side of the substrate; (c) inserting a heat discharge block into the heat discharge hole; (d) fixating the heat discharge block by stacking an insulation layer on the side opposite to the release film, heating and pressing the insulation layer; and (e) stacking the insulation layer by separating and removing the release film and forming a heat discharge pad by forming a conductive layer connected to the heat discharge block.

Description

인쇄회로기판 제조방법{METHOD OF MANUFACTURING A PRINTED CIRCUIT BOARD}[0001] METHOD OF MANUFACTURING A PRINTED CIRCUIT BOARD [0002]

본 발명은 인쇄회로기판(PCB; Printed Circuit Board)에 관한 것으로서, 특히 방열특성을 개선한 인쇄회로기판 제조방법에 관한 것이다. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board (PCB), and more particularly, to a method of manufacturing a printed circuit board with improved heat dissipation characteristics.

인쇄회로기판의 집적도가 증가함에 따라 기판에 실장된 부품에서 방출되는 방열량이 폭발적으로 증가하고 있다. 이에 따라, 부품에서 발생하는 열을 효율적으로 방사시켜 냉각시키는 기술이 인쇄회로기판 제조에 있어 주요 이슈로 부상하고 있다.As the degree of integration of a printed circuit board increases, the amount of heat dissipated from parts mounted on the board is explosively increasing. Accordingly, a technique of efficiently radiating and cooling heat generated from a component is emerging as a major issue in the manufacture of printed circuit boards.

도1은 종래기술에 따른 방열 인쇄회로기판을 나타내고 있다. 도1을 참조하면, 열발산(Heat Dissipation)을 효율적으로 촉진하기 위하여 제작된 열방출 홀(thermal hole; 30)을 나타내고 있으며, 열방출 홀(30) 내부는 열전도성이 양호한 금속으로 완전충진(Via Fill)되어 있다. 즉, 열방출 홀(30)의 내벽면에만 도전층을 피복하는 대신에, 홀 내부 전체를 열전도성이 양호한 금속으로 충진하는 기술이 요구되고 있다. 1 shows a heat-dissipating printed circuit board according to the prior art. Referring to FIG. 1, a heat dissipation hole 30 is formed to efficiently promote heat dissipation. The inside of the heat dissipation hole 30 is filled with a metal having a good thermal conductivity Via Fill). That is, instead of covering only the inner wall surface of the heat releasing hole 30 with the conductive layer, there is a demand for a technique of filling the whole hole with a metal having good thermal conductivity.

이에 따라, 종래기술은 열방출 홀 내부를 동도금으로 충진하기 위해 장시간 동도금을 실시하여야 하므로 공정비용이 상승하는 문제가 발생한다. 더욱이, 열방출 홀(thermal hole)을 충진하기 위해 동도금을 장시간 실시할 경우, 표면동박(40)의 두께도 함께 증가하므로 표면동박(40)의 미세패턴(fine pattern) 제작이 용이하지 않게 된다. 또한, 열방출 효율을 올리기 위해 방열 패드의 사이즈가 증가함에 따라 회로설계에 제한이 발생하는 문제점이 있다. Accordingly, the conventional technology requires a long period of copper plating to fill the inside of the heat-releasing hole with copper plating, which raises a problem that the process cost increases. Furthermore, when the copper plating is performed for a long time in order to fill a thermal hole, the thickness of the surface copper foil 40 also increases together, which makes it difficult to produce a fine pattern of the surface copper foil 40. In addition, as the size of the heat-radiating pad increases in order to increase the heat dissipation efficiency, the circuit design is limited.

1. 대한민국 특허공개 제10-2009-0066781호.1. Korean Patent Publication No. 10-2009-0066781. 2. 대한민국 특허공개 제10-2008-0100966호.2. Korean Patent Publication No. 10-2008-0100966. 3. 대한민국 특허공개 제10-2004-0051309호.3. Korean Patent Publication No. 10-2004-0051309.

본 발명의 제1 목적은 방열 인쇄회로기판 제조방법을 제공하는데 있다. A first object of the present invention is to provide a method of manufacturing a heat-dissipating printed circuit board.

본 발명의 제2 목적은 열방출 홀(thermal hole) 내부를 열전도성이 양호한 물질로 완전히 충진할 수 있는 방법을 제공하는데 있다. A second object of the present invention is to provide a method of completely filling the inside of a thermal hole with a material having a good thermal conductivity.

본 발명의 제3 목적은 상기 제1, 2 목적에 부가하여, 방열패드의 사이즈를 줄이고 미세회로 패턴을 제작할 수 있는 방법을 제공하는데 있다. A third object of the present invention is to provide a method of manufacturing a fine circuit pattern by reducing the size of the heat radiation pad, in addition to the first and second objects.

상기 목적을 달성하기 위하여, 본 발명은 홀 내부에 동도금을 실시하는 대신에 열방출 블록을 삽입하는 것을 특징으로 한다. In order to achieve the above object, the present invention is characterized by inserting a heat-releasing block instead of performing copper plating in a hole.

본 발명은 인쇄회로기판의 열방출 홀을 가공하는 방법에 있어서,(a) 기판에 열방출 홀을 천공하여 제작하는 단계; (b) 상기 기판의 일면에 이형필름을 부착하는 단계; (c) 상기 열방출 홀 속에 열방출 블록을 삽입하는 단계; (d) 이형필름 반대면에 절연층을 적층하고 가열가압하여 상기 열방출 블록을 고정하는 단계; 및 (e) 상기 이형필름을 분리제거하고 절연층을 적층하고, 상기 열방출 블록과 연결된 도전층을 형성하여 열방출 패드를 형성하는 단계를 포함하는 방법을 제공한다. The present invention relates to a method of processing a heat dissipation hole of a printed circuit board, comprising the steps of: (a) punching a heat dissipation hole in a substrate; (b) attaching a release film to one surface of the substrate; (c) inserting a heat releasing block into the heat releasing hole; (d) laminating an insulating layer on the opposite surface of the release film and pressing the heat release block by heating and pressing; And (e) separating and removing the release film, laminating an insulating layer, and forming a conductive layer connected to the heat releasing block to form a heat releasing pad.

본 발명은 종래기술과 달리 동도금을 실시하지 아니하고 홀 내부에 열방출 블록을 삽입하므로 공정비용과 공정시간을 감축할 수 있다, 더욱이, 동도금을 장시간 실시하지 않으므로 표면동박의 두께를 얇게 유지할 수 있으며, 그 결과 회로 피치를 미세화할 수 있다. 또한, 열전도 및 방사가 효율적으로 진행되므로 방열 패드를 크게 만들 필요가 없게 되고, 그 결과 회로설계 자유도가 개선된다. The present invention can reduce the processing cost and the process time by inserting the heat releasing block into the hole without performing the copper plating unlike the prior art. Further, since the copper plating is not performed for a long time, the thickness of the surface copper foil can be kept thin, As a result, the circuit pitch can be miniaturized. In addition, since heat conduction and radiation are efficiently performed, it is not necessary to make the heat radiating pad large, and as a result, the degree of freedom in circuit design is improved.

도1은 종래기술에 따른 열방출 홀 단면을 나타낸 도면.
도2a 내지 도2h는 본 발명에 따른 비아홀 충진방법을 나타낸 도면. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a conventional heat releasing hole. FIG.
2A to 2H are views showing a method of filling a via hole according to the present invention.

첨부도면 도2a 내지 도2k를 참조해서 본 발명에 따른 인쇄회로기판 제조기술의 양호한 실시예를 상세히 설명한다.A preferred embodiment of a printed circuit board manufacturing technique according to the present invention will be described in detail with reference to FIGS. 2A to 2K.

도2a를 참조하면, 제1 절연층(100) 양면에 제3 도전층(300)과 제4 도전층(400)을 형성한다. 제3 도전층(300)과 제4 도전층(400)은 비아홀(150)에 의해 연결되어 있다. 본 발명의 바람직한 실시예로서, 동박적층판(CCL; copper cladded laminate)를 사용할 수 있으며 에폭시수지층을 제1 절연층(100)으로 해서 양면의 동박을 선택적으로 식각하여 회로를 형성할 수 있으며, 레이저 가공을 통해 비아홀(150)을 형성하고 동도금을 실시하여 비아홀을 충진할 수 있다. Referring to FIG. 2A, a third conductive layer 300 and a fourth conductive layer 400 are formed on both sides of the first insulating layer 100. The third conductive layer 300 and the fourth conductive layer 400 are connected to each other by a via hole 150. As a preferred embodiment of the present invention, a copper clad laminate (CCL) can be used, a circuit can be formed by selectively etching the copper foil on both sides using the epoxy resin layer as the first insulating layer 100, The via hole 150 can be formed through the processing and copper plating can be performed to fill the via hole.

도2b를 참조하면, 기판 양면에 제2 절연층(110)과 제3 절연층(120)을 적층한다. 도2c를 참조하면, 각각 제2 절연층(110)과 제3 절연층(120) 위에 제2 도전층(200)과 제5 도전층(500)을 형성한다. 본 발명의 양호한 실시예로서, 레이저 비아홀을 가공하고 동도금을 실시한 후 선택적으로 식각을 실시하여 제2 도전층(200)과 제5 도전층(500)을 형성할 수 있다. Referring to FIG. 2B, a second insulating layer 110 and a third insulating layer 120 are stacked on both sides of a substrate. Referring to FIG. 2C, a second conductive layer 200 and a fifth conductive layer 500 are formed on the second insulating layer 110 and the third insulating layer 120, respectively. As a preferred embodiment of the present invention, the second conductive layer 200 and the fifth conductive layer 500 can be formed by processing the laser via holes, performing copper plating, and selectively etching.

도2d를 참조하면, 열방출 홀(250)을 가공한다. 본 발명에 따른 열방출 홀(250)은 CNC 기계 드릴 또는 펀치 방식으로 형성할 수 있다. 도2e를 참조하면, 기판의 일면에 이형필름(260; release film)을 부착한다. 본 발명의 이형필름(260)의 양호한 실시예로서 접착테이프, 프리프레그, 또는 접착필름 등의 절연재를 사용할 수 있다. Referring to FIG. 2D, the heat emission hole 250 is processed. The heat dissipation hole 250 according to the present invention can be formed by a CNC mechanical drill or a punch method. Referring to FIG. 2E, a release film 260 is attached to one side of the substrate. As a preferred embodiment of the release film 260 of the present invention, an insulating material such as an adhesive tape, a prepreg, or an adhesive film can be used.

도2f를 참조하면, 열방출 홀(250) 속에 열방출 블록(270)을 삽입한다. 본 발명에 따른 열방출 블록(270)은 열전도성의 도체로서 금속덩어리, 금속코인 등이 사용될 수 있다. Referring to FIG. 2F, the heat-releasing block 270 is inserted into the heat-releasing hole 250. The heat dissipation block 270 according to the present invention may be a metal lump, metal coin, or the like as a thermally conductive conductor.

도2g를 참조하면, 이형필름(260) 반대면에 제4 절연층(280)을 적층한다. 도2h를 참조하면, 이형필름(260)을 벗겨내어 제거한다. Referring to FIG. 2G, a fourth insulating layer 280 is stacked on the opposite surface of the release film 260. Referring to FIG. 2H, the release film 260 is peeled off and removed.

도2i를 참조하면, 이형필름(260)을 제거한 후 제5 절연층(290)을 적층한다. 도2j를 참조하면, 제1 도전층(111)과 제6 도전층(600)을 형성한다. 본 발명의 양호한 실시예로서, 제4 절연층(280)과 제5 절연층(290)에 비아홀을 가공하고 동도금을 실시함으로써 제1 도전층(111)과 제6 도전층(600)을 형성할 수 있다. 열 방출 패드(610, 620)가 형성되고, 기판 내부의 열방출 블록(270)이 열방출 패드(610, 620)와 접속되어 열전달이 이루어진다. 마지막으로, 도2k를 참조하면 솔더레지스트(710)을 프린트하여 도포한다. Referring to FIG. 2I, after the release film 260 is removed, the fifth insulating layer 290 is laminated. Referring to FIG. 2J, a first conductive layer 111 and a sixth conductive layer 600 are formed. The first conductive layer 111 and the sixth conductive layer 600 are formed by processing a via hole in the fourth insulating layer 280 and the fifth insulating layer 290 and performing copper plating as a preferred embodiment of the present invention . The heat releasing pads 610 and 620 are formed and the heat releasing block 270 inside the substrate is connected to the heat releasing pads 610 and 620 to perform heat transfer. Finally, referring to FIG. 2K, the solder resist 710 is printed and applied.

전술한 내용은 후술할 발명의 특허 청구 범위를 더욱 잘 이해할 수 있도록 본 발명의 특징과 기술적 장점을 다소 폭넓게 개선하였다. 본 발명의 특허 청구 범위를 구성하는 부가적인 특징과 장점들이 이하에서 상술 될 것이다. 개시된 본 발명의 개념과 특정 실시예는 본 발명과 유사 목적을 수행하기 위한 다른 구조의 설계나 수정의 기본으로서 즉시 사용될 수 있음이 당해 기술 분야의 숙련된 사람들에 의해 인식되어야 한다. The foregoing has somewhat improved the features and technical advantages of the present invention in order to better understand the claims of the invention described below. Additional features and advantages that constitute the claims of the present invention will be described in detail below. It is to be appreciated by those skilled in the art that the disclosed concepts and specific embodiments of the invention can be used immediately as a basis for designing or modifying other structures to accomplish the invention and similar purposes.

또한, 본 발명에서 개시된 발명 개념과 실시예가 본 발명의 동일 목적을 수행하기 위하여 다른 구조로 수정하거나 설계하기 위한 기초로서 당해 기술 분야의 숙련된 사람들에 의해 사용될 수 있을 것이다. 또한, 당해 기술 분야의 숙련된 사람에 의한 그와 같은 수정 또는 변경된 등가 구조는 특허 청구 범위에서 기술한 발명의 사상이나 범위를 벗어나지 않는 한도 내에서 다양한 진화, 치환 및 변경이 가능하다. In addition, the inventive concepts and embodiments disclosed herein may be used by those skilled in the art as a basis for modifying or designing other structures to accomplish the same purpose of the present invention. It will be apparent to those skilled in the art that various modifications, substitutions and alterations can be made hereto without departing from the spirit or scope of the invention as defined in the appended claims.

본 발명은 종래기술과 달리 동도금을 실시하지 아니하고 홀 내부에 열방출 블록을 삽입하므로 공정비용과 공정시간을 감축할 수 있다, 더욱이, 동도금을 장시간 실시하지 않으므로 표면동박의 두께를 얇게 유지할 수 있으며, 그 결과 회로 피치를 미세화할 수 있다. 또한, 열전도 및 방사가 효율적으로 진행되므로 방열 패드를 크게 만들 필요가 없게 되고, 그 결과 회로설계 자유도가 개선된다. The present invention can reduce the processing cost and the process time by inserting the heat releasing block into the hole without performing the copper plating unlike the prior art. Further, since the copper plating is not performed for a long time, the thickness of the surface copper foil can be kept thin, As a result, the circuit pitch can be miniaturized. In addition, since heat conduction and radiation are efficiently performed, it is not necessary to make the heat radiating pad large, and as a result, the degree of freedom in circuit design is improved.

250 : 열방출 홀
260 : 이형필름
270 : 열방출 블록250: Heat dissipation hole
260: release film
270: Heat dissipation block

Claims (1)

인쇄회로기판의 열방출 홀을 가공하는 방법에 있어서,
(a) 기판에 열방출 홀을 천공하여 제작하는 단계;
(b) 상기 기판의 일면에 이형필름을 부착하는 단계;
(c) 상기 열방출 홀 속에 열방출 블록을 삽입하는 단계;
(d) 이형필름 반대면에 절연층을 적층하고 가열가압하여 상기 열방출 블록을 고정하는 단계; 및
(e) 상기 이형필름을 분리제거하고 절연층을 적층하고, 상기 열방출 블록과 연결된 도전층을 형성하여 열방출 패드를 형성하는 단계
를 포함하는 방법. A method of processing a heat dissipation hole of a printed circuit board,
(a) fabricating a substrate by drilling a heat dissipation hole;
(b) attaching a release film to one surface of the substrate;
(c) inserting a heat releasing block into the heat releasing hole;
(d) laminating an insulating layer on the opposite surface of the release film and pressing the heat release block by heating and pressing; And
(e) separating and removing the release film, laminating an insulating layer, and forming a conductive layer connected to the heat releasing block to form a heat releasing pad
≪ / RTI >
KR1020130035302A 2013-04-01 2013-04-01 Method of manufacturing a printed circuit board KR20140119517A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109561572A (en) * 2018-11-30 2019-04-02 景旺电子科技(龙川)有限公司 A kind of more boss types partly insertion copper billet printed board and preparation method thereof
CN112888181A (en) * 2020-11-06 2021-06-01 惠州市盈帆实业有限公司 Production method of copper-embedded mixed-compression circuit board based on PVC material
CN114190011A (en) * 2021-11-11 2022-03-15 江苏普诺威电子股份有限公司 High-heat-dissipation PCB and manufacturing process thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109561572A (en) * 2018-11-30 2019-04-02 景旺电子科技(龙川)有限公司 A kind of more boss types partly insertion copper billet printed board and preparation method thereof
CN112888181A (en) * 2020-11-06 2021-06-01 惠州市盈帆实业有限公司 Production method of copper-embedded mixed-compression circuit board based on PVC material
CN114190011A (en) * 2021-11-11 2022-03-15 江苏普诺威电子股份有限公司 High-heat-dissipation PCB and manufacturing process thereof
CN114190011B (en) * 2021-11-11 2024-02-23 江苏普诺威电子股份有限公司 High-heat-dissipation PCB and manufacturing process thereof

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