KR20120017530A - Circuit board using anodizing and manufacturing method of the same - Google Patents

Abstract

PURPOSE: A circuit board using anodizing and a manufacturing method thereof are provided to simplify processes by omitting a formation process of a via hole and directly forming an insulation part on a raw material metal board. CONSTITUTION: A dry film is laminated and a masking pattern is formed. Metal is coated on an exterior of an exposed metal board. A photoresist layer is stripped and a circuit pattern layer is formed. An part of the metal board exposed by the circuit pattern layer is anodized and changed into an insulating layer(261-263) and circuit pattern layers are electrically connected by the rest part of the metal board.

Description

Circuit board using anodizing and manufacturing method thereof {CIRCUIT BOARD USING ANODIZING AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a circuit board and a method of manufacturing the same, and more particularly, by forming an insulator directly on a raw metal substrate without forming a via hole, thereby anodizing the etching or drill process and plating process required for via hole processing can be omitted. It relates to a circuit board and a method of manufacturing the same.

In general, a circuit board is a substrate in which many components of various kinds are mounted on a flat plate made of phenol resin or epoxy resin, and a circuit for electrically connecting each component is densely fixed on the surface of the resin flat plate. Alternatively, a thin plate of copper or the like is laminated on one surface of an epoxy resin insulating plate, and then etched according to the wiring pattern of the circuit to form a necessary circuit, and a hole is formed for attaching and mounting the parts to be electrically connected to each layer. Recently, multilayer printed circuit boards having improved integration have emerged as electronic products are lighter and shorter, higher in density, packaged, and more portable, and fine patterns are also used in the multilayer printed circuit board. Miniaturization, miniaturization and packaging are in progress. Such conventional substrates are classified into printed circuit boards (PCBs) and flexible printed circuit boards (FPCBs) according to a use purpose.

In the printed circuit board, a conductive copper foil layer is formed on and under the insulating layer to form a wire in the conductive copper foil layer, and a via penetrating through the insulating layer is formed in the conductive copper foil layer to allow electrical connection. In addition, the flexible printed circuit board is based on a structure in which a conductive copper foil layer is interposed between the upper and lower insulating layers of a polymer material.

Here, as an example of the circuit board, a method of manufacturing a printed circuit board (PCB) will be described in more detail with reference to FIG. 1. First, as shown in FIG. 1A, the insulating board 103 is disposed on both surfaces thereof. A copper clad laminate (CCL) 101 having a thin copper foil 102 formed thereon is provided. Here, the copper-clad laminate 101 is a disk made of a printed circuit board is generally a thin laminated board with a thin copper coating on the insulating layer, according to the purpose of the glass / epoxy copper laminated board, heat-resistant resin copper laminated board, paper / phenol copper laminated board There are many kinds of high frequency copper clad laminates, flexible copper clad laminates (polyimide films) and composite copper clad laminates, but glass / epoxy copper clad laminates are mainly used for double-sided PCBs and multilayer PCBs.

Thereafter, as shown in FIGS. 1B and 1C, via holes 104 for interlayer connection are formed in the copper-clad laminate 101 by drilling, and then electroless copper plating and electrolysis of the copper foil layers and via holes. Copper plating is performed to form the copper plating layer 105.

Here, electroless copper plating is performed first and then electrolytic copper plating is performed because electrolytic copper plating that requires electricity cannot be performed on the insulating layer. That is, in order to form the electroconductive film required for electrolytic copper plating, electroless copper plating is thinly performed as the pretreatment. Since electroless copper plating is difficult to process and economically disadvantageous, it is preferable to form the conductive portion of the circuit pattern by electrolytic copper plating. After the electroless and electrolytic copper plating is performed as described above, as shown in FIG. 1D, paste is applied to the inner region of the via hole to protect the electroless and electrolytic copper plating layer 105 formed on the inner wall of the via hole 104. Fill (106).

Here, the paste 106 generally uses an insulating ink material, but a conductive paste may also be used depending on the purpose of the printed circuit board. The conductive paste is obtained by mixing a metal such as Cu, Ag, Au, Sn, Pb as a main component alone or in an alloy form with an organic adhesive. Subsequently, as shown in FIGS. 1E and 1F, an ultraviolet ray irradiation is performed on an artwork film having a predetermined circuit pattern to transfer the predetermined circuit pattern to the photosensitive dry film, thereby forming an etching resist pattern for forming an inner circuit pattern. After forming 107, by performing an etching process using a predetermined etching solution, the copper foil layer 105 in the region where the etching resist pattern 107 is not formed is removed to form a predetermined circuit pattern. After the circuit pattern is formed as described above, as shown in FIGS. 1G and 1H, an electrical connection between an inner layer and an outer layer is formed by laminating using Resin Coated Copper (RCC) or a coreless material on both sides of the substrate. Process the via hole 110 to perform the.

As described above, the conventional printed circuit board is formed by etching copper foil laminated disk 101 by copper foil on upper and lower surfaces of insulating layer 103, and electrical connection of copper foil laminated disk 101 is performed by a drill or a laser. Since the via hole 110 is to be formed through mechanical processing, the manufacturing process is complicated as a plurality of lamination processes are involved, and the manufacturing cost increases due to various processes.

In addition, the conventional substrate has a low heat transfer efficiency of the insulating layer 103 interposed between the copper clad laminate disk 101, so that the heat generated by the high heat dissipating element, such as a high power element such as PAM or LED, can be easily transferred to the outside. There is a disadvantage that can not be released.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to simplify the process by eliminating the etching or drilling process for forming the via holes and the plating process for filling the via holes, thereby reducing the heat dissipation effect of the mounted chip. The present invention provides a circuit board using anodizing and a method of manufacturing the same.

According to an embodiment of the present invention, a method for manufacturing a circuit board using anodizing may include: (a) forming a conductive circuit pattern layer on both sides of a metal substrate; (b) anodizing the metal substrate portion exposed by the circuit pattern layer and converting the metal substrate portion into an insulating layer, thereby electrically connecting the circuit pattern layers on both sides by the remaining metal substrate portion.

Here, the material of the metal substrate of step (a) may be any one of aluminum, magnesium, titanium.

In addition, the step (a), (a1) laminating the dry film on both sides on the metal substrate, and forming a masking pattern on the dry film, and then exposing and developing; (a2) plating metal on an outer surface of the metal substrate exposed by the developed photoresist layer; And (a3) removing the photoresist layer to form a circuit pattern layer. In this case, the metal of step (a2) is preferably copper.

On the other hand, the step (a) may be a step of forming a pattern of the circuit pattern layer of the both sides is different, in this case, the step (b), the portion of the metal substrate exposed both sides is the thickness of the metal substrate Anodizing all of the, and the exposed portion only one surface may be anodizing all or part of the thickness of the metal substrate.

In addition, the structure of the circuit board using anodizing according to the present invention, the substrate comprising a conductive portion and the anodized insulating portion; And a circuit pattern layer formed on both sides of the substrate to be electrically connected by the conductive portion.

Herein, the conductive part may be made of any one of aluminum, magnesium, and titanium, and the insulating part may be an anodized material.

In addition, the material of the circuit pattern layer is preferably copper.

In addition, the insulating portion may have a form in which the width decreases toward the center of the substrate.

According to the present invention, by forming the insulating layer directly on the raw material metal substrate without forming the via holes, the etching or drill process and the plating process required for via hole processing can be omitted. As a result, the contamination of the etching bath due to the metal ions resulting from the etching of the metal substrate can be prevented, and the heat dissipation efficiency can be improved as the anodized insulating layer itself uses the metal substrate.

1 is a cross-sectional view showing a manufacturing process of a circuit board according to the prior art.
2 is a cross-sectional view of a circuit board manufacturing process using anodizing according to an embodiment of the present invention;

Hereinafter, a circuit board using anodizing and a method of manufacturing the same will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid unnecessarily obscuring the subject matter of the present invention.

In addition, the size of each component in the drawings may be exaggerated for the purpose of description, and does not mean the size that is actually applied, terms such as first, second, etc. is intended to distinguish one component from other components Only used as

2 is a cross-sectional view of a circuit board manufacturing process using anodizing according to an embodiment of the present invention. Referring to FIG. 2, first, a metal substrate 210 to be used as a raw material is prepared (FIG. 2A). The metal substrate 210 may be made of any one metal material of aluminum, magnesium, and titanium. Thereafter, the photoresist layer, for example, the photosensitive dry film 220, is laminated on both surfaces of the metal substrate 210 (FIG. 2B). In addition, an artwork film 230 having a masking pattern, for example, a predetermined circuit pattern, is formed on the outer surface of the photosensitive dry film 220 (FIG. 2C). After the ultraviolet irradiation of the artwork film 230 on which the predetermined circuit pattern is formed, the development process is performed to form an etching resist pattern 225 for forming the circuit pattern (FIG. 2D). Then, the metal is plated on the outer surface of the metal substrate 210 exposed by the etching resist pattern 225 (FIG. 2E). In this case, the plating layer 240 is preferably made of a copper material. Thereafter, the etching resist pattern 225 is peeled off (FIG. 2F). Due to such peeling, circuit pattern layers 241 to 247 are formed on both surfaces of the metal substrate 210. The circuit pattern layers 241 to 247 formed on both surfaces of the metal substrate are constituted by circuit pattern layers 242 and 245 including portions not opposed to the circuit pattern layers 241 and 244 and 243 and 247 facing each other. Can be.

Thereafter, anodizing process is performed using the circuit pattern layers 241 to 247 on both sides of the metal substrate 210 as masks (FIG. 2G). Here, anodizing means anodizing of an anode and a cathode as a metal surface treatment method. The electrons must be collected well, so an oxide film is applied. On the other hand, its origin, anode, means the positive electrode of a tube / diode, and the opposite negative electrode is called a cathode. In particular, various products made of aluminum metal are easily deteriorated and corroded when they are used as they are, because physical and chemical properties of the aluminum metal are weak, thereby deteriorating their appearance and function. By supplementing and improving these vulnerabilities, the aluminum metal surface is improved in strength, abrasion resistance, corrosion resistance, electrical insulation by several tens to hundreds of times, depending on the applied method than its original properties, and the surface has a beautiful and heavy metal texture. In particular, it can be processed in a variety of colors to increase the functionality and product value.

This treatment method is called anodizing, alu-mite, aluminum oxide film treatment, and the specific working method is different, but it can be understood as the same meaning for the purpose of forming an oxide film on the aluminum metal surface.

In the anodizing process, since a circuit pattern layer formed on both sides of the metal substrate is used as a mask, a separate pattern mask for anodizing is not required, thereby improving the efficiency of the process. In this case, the exposed portions of both sides of the metal substrate may anodize all of the thickness of the metal substrate, and the exposed portions of only one surface may anodize all or part of the thickness of the metal substrate.

By this anodizing process, a circuit board as shown in FIG. 2H is formed. Specifically, by anodizing, a portion of the metal substrate 210 is converted into the insulating portions 261, 262, and 263, and the remaining non-anodized portions form the conductive portions 251 to 255. The circuit pattern layer 241 is electrically connected to the circuit pattern layer 244 through the conductive portion 251, and the circuit pattern layer 242 is the circuit pattern layer 245 through the conductive portions 252, 255, and 253. And 246, and the circuit pattern layer 243 is electrically connected to the circuit pattern layer 247 through the conductive portion 254.

In addition, the circuit patterns layers 241 and 244, the circuit pattern layers 242, 245 and 246, and the circuit pattern layers 243 and 247 are electrically insulated from each other due to the insulating parts 261 to 263 converted by anodizing. do. On the other hand, with respect to the degree of anodizing, the exposed portions of the metal substrate 210 anodize all the thicknesses of the metal substrate 210 to form the insulation portions 261 and 263, and the exposed portions of the metal substrate 210 are metal substrates. An insulating portion 262 may be formed by anodizing a portion of the thickness 210. In this case, even if the couple exposed only one side of the thickness of the metal substrate 210 is all anodized, the circuit pattern layers 242, 245, and 246 may be electrically connected to each other through the conductive parts 252 and 253, but the metal substrate 210 may be electrically connected. The electrical conductivity may be improved by anodizing only a portion of the thickness to form the conductive portion 255.

As such, the manufacturing process may omit complicated processes such as etching, drilling, and laser processes for drilling via holes in order to electrically connect the circuit pattern layers 241 to 247 formed on both surfaces of the metal substrate 210. Contamination of the etching bath by the metal ions emitted from the generated metal substrate can be prevented. In addition, the circuit pattern layer is formed before the anodizing process, and can be used as the anodizing mask itself, thereby improving process efficiency and cost. In addition, when the chip is mounted on the circuit board, since the insulating portion is converted from the metal substrate, the heat dissipation effect may be superior to that of the separately formed insulating portion without anodizing. The same effect can be obtained by applying such a circuit board to various fields such as a printed circuit board (PCB), LED, BGA, and lead frame.

In the foregoing detailed description of the present invention, specific examples have been described. However, various modifications are possible within the scope of the present invention. The technical spirit of the present invention should not be limited to the above-described embodiments of the present invention, but should be determined by the claims and equivalents thereof.

210: metal substrate 220: photosensitive dry film
225: etching resist pattern 230: artwork film
240: plating layers 261, 262, 263: insulation
241, 242, 243, 244, 245, 246 and 247: circuit pattern layer
251, 252, 254, 254, 255: Challenge

Claims (10)

(a) forming conductive circuit pattern layers on both sides of the metal substrate;
(b) anodizing and converting the metal substrate portion exposed by the circuit pattern layer into an insulating layer, thereby electrically connecting the circuit pattern layers on both sides by the remaining metal substrate portion. Circuit board manufacturing method.
The method of claim 1,
The material of the metal substrate of step (a) is a circuit board manufacturing method using anodizing any one of aluminum, magnesium, titanium.
The method of claim 1,
In step (a),
(a1) laminating a dry film on both sides of the metal substrate, forming a masking pattern on the dry film, and then exposing and developing the film;
(a2) plating metal on an outer surface of the metal substrate exposed by the developed photoresist layer; And
(a3) A method of manufacturing a circuit board using anodizing, comprising: peeling the photoresist layer to form a circuit pattern layer.
The method of claim 3,
The metal of step (a2) is a circuit board manufacturing method using anodizing copper.
The method of claim 1,
In the step (a), the circuit board manufacturing method using anodizing is formed so that the patterns of the circuit pattern layers on both sides are different.
6. The method of claim 5,
In step (b),
The exposed portion of the metal substrate on both sides is anodizing the entire thickness of the metal substrate, the exposed portion only one surface is a step of anodizing all or part of the thickness of the metal substrate.
A substrate including a conductive portion and an anodized insulating portion;
A circuit board using anodizing comprising a circuit pattern layer formed on both sides of the substrate to be electrically connected by the conductive portion.
The method of claim 7, wherein
The conductive part may be made of any one of aluminum, magnesium, and titanium, and the insulating part is an anodized circuit board using any one material.
The method of claim 7, wherein
The material of the circuit pattern layer is a circuit board using anodizing copper.
The method of claim 7, wherein
The insulating portion is a circuit board using anodizing that decreases in width toward the center of the substrate.

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