TWI529068B - Method for producing substrate formed with copper thin layer, method for manufacturing printed circuit board and printed circuit board manufactured thereby - Google Patents

Description

a production method of a substrate having a thin copper layer, and a method of manufacturing a printed circuit board And a printed circuit board manufactured by the above method

The present invention relates to a method for producing a substrate having a thin copper layer and a method for producing a printed circuit board. More particularly, the present invention relates to a production method of a substrate having a thin copper layer, which is suitable for use in the manufacture of a printed circuit board having a fine pattern circuit, and a method of manufacturing a printed circuit board.

A printed circuit board (PCB) refers to a plurality of electronic components that are fixedly and electrically connected to construct a circuit. Generally, the printed circuit board includes an insulating substrate, a conductive pattern on the insulating substrate, and a plurality of through holes through which the components are fixedly and electrically connected to each other.

Printed circuit boards can be classified into rigid printed circuits (rigid PCBs), flexible printed circuit boards (FPCBs), and rigid-flexible printed circuit boards (R-F PCBs). In a rigid printed circuit board, a copper foil is attached to a core material obtained by reinforcing an epoxy resin using a suitable material (for example, glass fiber). In a flexible printed circuit board, a copper foil is attached to a polyimine. The rigid-flexible printed circuit board is a combination of a rigid printed circuit board and a flexible printed circuit board to provide the advantages of two types of printed circuit boards. The application of these printed circuit boards is determined by their characteristics. With the recent trend towards lightweight, thin and small-sized electronic devices, the demand for printed circuit boards that occupy small spaces has increased plus. Miniaturization of printed circuit boards requires lamination of circuit patterns or reduction of spacing between circuit wirings.

According to a conventional method of forming a circuit pattern in a printed circuit board, a The dry film forms a mask pattern on a copper foil, and the copper foil is etched to form an electrical circuit. This method has limitations in controlling the pitch between wirings of the circuit to 60 μm or less. In an attempt to overcome the limitations encountered in forming fine circuit patterns, new technologies, such as the semi-additive process (SAP), have recently been introduced. This semi-additive method is one of the opposite concepts to the conventional etching method. According to the semi-additive method, a region other than the circuit formation region is shielded by a suitable mask material (for example, a dry film), and then directly plated in a region where the circuit is to be formed to form a conductive pattern.

Even if the semi-additive method is applied, a thin copper foil is required for the formation of a fine pattern. Use. The copper foil is a base layer which serves as one of the electrodes for direct plating. However, this thin copper foil can only be obtained from a few suppliers because it is difficult to produce. Due to the high price of thin copper foil, printed circuit board manufacturers purchase inexpensive thick copper foil and etch them to the desired thickness before use. However, additional etching involves an additional increase in production costs and causes environmental pollution problems.

Many production procedures for copper foil for printed circuit boards have been widely known. For example A copper foil for the production of a copper clad laminate, and a copper clad laminate including the copper foil are disclosed in Korean Patent Publication No. 2012-0084441. However, when a copper foil is laminated on a carrier, diffusion occurs between the carrier aluminum and the copper. This diffusion makes the carrier aluminum layer difficult to peel off, and thus it is difficult for the copper foil to obtain a uniform surface. Further, Korean Patent Registration No. 728764 describes a technique for depositing copper particles by sputtering. This technology contributes to the simplification of the production process, the improvement of production efficiency, and the thinning of the substrate. However, this patent document does not disclose the production of a thin copper foil.

The first object achieved by a specific embodiment of the present invention provides a A method for producing a substrate composed of a thin layer of copper which avoids diffusion on a interface between a carrier and the thin layer of copper, facilitating separation between the carrier and the thin layer of copper.

A second object achieved by an embodiment of the present invention provides a printing A method of manufacturing a circuit board using the production method of the substrate having a thin copper layer.

A third object achieved by an embodiment of the present invention provides a printing A circuit board manufactured by the manufacturing method.

A fourth object achieved by an embodiment of the present invention provides a A substrate composed of a thin layer of copper produced by the production method.

According to an embodiment of the invention, the first object is by a thin copper Providing a method for producing a substrate composed of a layer, the method comprising: providing a carrier; forming a separation inducing layer on a surface of the carrier; forming a thin layer of copper on the separation inducing layer; and combining a core To the thin layer of copper.

According to an exemplary embodiment of the present invention, the carrier may be composed of aluminum, and The separation inducing layer can be formed by forming a porous layer on the surface of the support and coating a sealant on the surface of the support having the porous layer.

According to a further exemplary embodiment of the invention, the porous layer may use one A solvent is formed on the surface of the support, the solvent comprising at least one compound selected from the group consisting of a basic compound, an iron compound, and a carbonic acid compound.

According to another further exemplary embodiment of the present invention, the porous layer can be Electroless etching is formed on the surface of the carrier.

According to another further exemplary embodiment of the invention, the surface of the carrier is shaped The porous layer can be formed using aluminum.

According to another further exemplary embodiment of the invention, the coating has a plurality of The sealant on the surface of the carrier formed by the aperture layer may comprise at least one material selected from the group consisting of metal-polymer composites, cobalt-chromium, boron nitride, molybdenum disulfide, and polytetrafluoroethylene.

According to an embodiment of the present invention, the second object is by a printed circuit Provided by the method of manufacturing a board comprising: providing a substrate having a thin layer of copper produced by the production method; separating the carrier and the separation inducing layer from the substrate; and forming the separation layer on the copper layer Forming a mask for patterning and forming a copper pattern by plating on the copper thin layer; removing the mask for patterning; and removing the copper thin layer to leave a patterned copper circuit .

According to an embodiment of the present invention, the third object is by a system The manufacture of printed circuit boards manufactured by the method is achieved.

According to an embodiment of the invention, the fourth object is achieved by a substrate The substrate comprises: a carrier made of aluminum; a separation inducing layer formed on the surface of the carrier; a thin layer of copper formed on the separation inducing layer; And a core bonded to the copper thin layer, wherein the separation inducing layer is composed of a porous aluminum layer and a sealing layer formed on the porous aluminum layer.

The production method and the manufacturing method according to the specific embodiment of the present invention have the following Benefits.

First, in the process of attaching the core to the copper foil by hot pressing, the carrier layer and copper The separation between the thin layers induces the presence of a layer to prevent diffusion between the carrier layer and the copper thin layer. Therefore, the carrier can be easily separated from the copper thin layer and the thickness and surface roughness of the separated copper thin layer can be maintained.

Second, the formation of the separation inducing layer comprises forming the porous layer in aluminum On the surface of the carrier, and the porous layer is formed using aluminum, not alumina. Thus, the support can be removed by chemical etching using a single etching solution.

Third, in the substrate produced according to the specific embodiment of the present invention, the copper thin layer can be It is formed and made to have a thickness small enough. Therefore, when a half-additive method is applied, the thin layer of the underlying copper to be etched is thin, which is advantageous for the formation of a fine circuit pattern.

100‧‧‧Printed circuit board

110‧‧‧core

120‧‧‧Adhesive layer

130‧‧‧thin copper layer

200‧‧‧Substrate

210‧‧‧core

220‧‧‧Adhesive layer

230‧‧‧ copper thin layer

240‧‧‧ Carrier

241‧‧‧Porous layer

242‧‧‧ Sealing layer

S1‧‧‧Step one

S2‧‧‧Step 2

S3‧‧‧Step three

S4‧‧‧Step four

S5‧‧‧Step five

S6‧‧‧Step six

S7‧‧‧Step seven

S8‧‧‧Step eight

S9‧‧‧Step nine

S10‧‧‧Step ten

S11‧‧‧Step XI

Figure 1 is a cross-sectional view showing the structure of a general printed circuit board.

Figure 2 is a cross-sectional view showing a substrate structure having a thin layer of copper produced in accordance with an embodiment of the present invention.

Figure 3 is a flow chart showing a method of manufacturing a prior art multilayer printed circuit board.

Figure 4 is a flow chart illustrating a method of fabricating a printed circuit board in accordance with an embodiment of the present invention.

The above and other specific embodiments and advantages of the present invention will become more apparent and appreciated from the <RTIgt;

A specific embodiment of the present invention provides a method for producing a substrate having a thin layer of copper, the method comprising: providing a carrier; forming a separation inducing layer on a surface of the carrier; forming a copper on the separation inducing layer a thin layer; and a core to the copper thin layer.

Specific embodiments of the invention are described herein in more detail with reference to the appended drawings. These specific embodiments are provided so that these disclosures will fully convey the scope of the invention to those skilled in the art. The invention may be embodied in many different forms and should not be construed as being limited to the exemplary embodiments disclosed herein. For clarity, the dimensions of the elements such as width, length and thickness may be exaggerated. It will be understood that when an element is referred to as "on" another element, it can be s 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Furthermore, where a method includes one or more sequential steps, one or more steps can be between the sequential steps. This step may not be limited to this order, if desired, and may be performed in other orders.

Figure 1 is a cross-sectional view showing the structure of a general printed circuit board. Referring to FIG. 1, the printed circuit board 100 includes a core 110, an adhesion layer 120, and a thin copper layer. 130. The core 110 can be fabricated from a rigid or soft material. The core 110 made of a rigid material is used to manufacture a rigid printed circuit board, and the core 110 made of a soft material is used to manufacture a flexible printed circuit board. For example, the rigid material can be a metal, glass or a combination of epoxy and glass fibers, and the soft material can be a polyimide resin. The adhesion layer functions to bond the core and the copper layer, and the copper layer can be patterned to construct an electrical circuit.

There are many ways to construct a circuit in a printed circuit board using a thin layer of copper. According to this issue In a specific embodiment, a thin layer of copper can be formed and have a thickness that is sufficiently small and uniform, thereby facilitating the formation of a fine pattern circuit by semi-additive.

Figure 2 is a diagram showing copper produced in accordance with an embodiment of the present invention. A cross-sectional view of a substrate structure composed of a thin layer. Referring to FIG. 2, the substrate 200 includes a core 210, an adhesion layer 220, a copper thin layer 230, a sealing layer 242, a porous layer 241, and a carrier 240. The core 210 is a substrate of a printed circuit board and may be fabricated from a rigid material or a soft material. For example, the rigid material can be a metal, glass or an epoxy/glass fiber composition, and the soft material can be a polyimide resin. The core 210 can be a structure for a printed circuit board, such as a metal, glass or combination of epoxy and fiberglass, or a polymeric film such as PET or PEN. The core can be adapted for use in an application. Although not shown in the drawings, the substrate 200 may optionally further comprise a layer of thermoplastic resin on the surface of the core 210, where the adhesion layer 220 will be formed. The adhesion layer acts to bond the copper thin layer 230 to the core 210. A variety of polymer resin adhesives can be used as the material of the adhesion layer 220. When a core is composed of polyimine, the adhesion layer 220 can be formed using an adhesive that is highly compatible with one of the polyimides. The copper thin layer 230 constitutes a circuit pattern of a printed circuit board. The circuit pattern can be formed by etching or semi-additive. When a half-additive method is applied, a thin copper layer having a predetermined pattern may be formed on the copper thin layer 230. The carrier 240 is bonded to the copper thin layer 230. The porous layer 241 and one of the sealing layer 242 may be separated and induced It is formed between the copper thin layer 230 and the carrier 240. The separation inducing layer functions to prevent the metal composition of the carrier and the copper of the copper layer from being mutually diffused when the copper thin layer and the core are bonded by hot pressing, which is facilitated in a subsequent processing step. The separation between the carrier and the thin layer of copper while maintaining the consistent thickness and surface roughness of the separated copper layer.

Here, the production of a substrate having a thin layer of copper according to an embodiment of the present invention is produced. The method is described based on individual steps.

First, a carrier is provided. An aluminum sheet can be used as a carrier. a release paper Attached to one side of the carrier by a pressure sensitive adhesive.

Subsequently, a porous layer is formed on at least one side of the carrier. The porous layer It is formed by treating an aluminum sheet with a solvent containing a basic compound, an iron compound or a carbonic acid compound as a main component and at least one functional additive. For example, the basic compound may be sodium hydroxide (NaOH) or potassium hydroxide (KOH), and the iron compound may be iron cyanide or ferric citrate, and the carbonic acid compound may be potassium carbonate or sodium carbonate, and the The functional additive can be a chelating agent. That is, the step of forming the porous layer is carried out by treating the surface of aluminum with a chemical, and does not require electrical use, unlike the anodizing procedure using electricity. This chemical treatment, along with microetching, is a concept for the formation of micropores on aluminum surfaces. The electroless drug treatment can be a procedure for etching the aluminum surface to form the porous layer. Specifically, this procedure can be carried out by soaking the aluminum support to the chemical at about 40 ° C to about 60 ° C for about 3 minutes to about 10 minutes. In general, anodization uses electricity to form a non-conductive layer. In contrast, the porous layer is formed by the chemical treatment, and has a structure in which only micropores are formed in the base material. Due to this structure, the properties of the base material as a conductor remain unchanged, and thus the current carrying characteristics of the porous layer are not affected by the chemical treatment. Since the main composition of the porous layer is not aluminum but aluminum, the carrier can be separated and removed from a thin layer of copper by a chemical procedure using only an etching solution for aluminum removal. A small amount of other components such as aluminum hydroxide may remain in the porous layer. However, due to the small thickness of these compositions, the aluminum is etched In the process, it can be separated and removed by an etching solution.

Subsequently, a sealing layer is formed over the porous layer. This step is optional. The sealing layer functions as a lubricant to separate the carrier from a thin layer of copper, wherein the thin layer of copper will be formed over the sealing layer. The sealing layer fills the micropores of the porous layer, and the effect is to smooth the surface of the copper thin layer, and prevent a kind of aluminum and copper of the carrier during the process of bonding a core to the copper thin layer by hot pressing. An alloy layer caused by the diffusion of thin layers of copper between each other. The sealing layer can be formed using an inorganic or organic material or a polymer resin. Materials suitable for the sealing layer include, for example, boron nitride (BN), molybdenum disulfide (MoS ₂ ), Teflon, and polytetrafluoroethylene (PTFE). Alternatively, a metal-polymer composition such as a chromium-polymer composition, or a metal material such as cobalt-chromium may also be used to form the sealing layer. Although FIG. 2 shows that the porous layer and the sealing layer are laminated in a different order from each other, the constituent material of the sealing layer may be filled in the micropores of the porous layer. The porous layer forms a separation inducing layer with the sealing layer. The porous layer is a porous aluminum layer and the sealing layer is coated on the porous layer. That is, the separation inducing layer has a structure in which the sealing layer is formed on the porous aluminum layer.

The separation inducing layer is formed of the porous layer and the sealing layer on the carrier and the Between the thin layers of copper. The absence of the separation inducing layer will result in diffusion between the carrier and the interface of the copper layer during the hot pressing of the copper thin layer and a core at a high temperature of 350 ° C or higher. This diffusion makes it difficult to separate the carrier from the thin layer of copper. On the other hand, the presence of the separation inducing layer between the support and the copper thin layer prevents the aluminum of the support from forming a diffusion layer with the copper thin layer of copper at a high temperature, and the aluminum support can be chemically etched. In the process of separating the copper thin layer, it is only necessary to use an aluminum etching solution without using an alumina etching solution, which simplifies the production process and reduces the production cost.

Subsequently, a thin layer of copper is formed over the sealing layer. The copper thin layer can be used without Electroplated copper is formed. The thin layer of copper formed by electroless copper is formed based on a chemical reaction mechanism that does not use electricity. The copper thin layer can be plated to have a uniform thickness from submicron to tens of microns. Therefore, depending on the thickness of the copper thin layer, a circuit pattern can be formed by etching or semi-additive. The electroless copper can be obtained from Displacement copper plating and electroless reduction copper plating are suitably selected, wherein the replacement copper plating is based on different ionization tendency, and the electroless reduction copper plating is based on a reducing agent function according to a desired application.

Subsequently, a core is bonded to the thin layer of copper. For this combination, an adhesive layer or An undercoat layer may be formed between the core and the thin layer of copper. The adhesive layer or primer layer can be formed using a material that is highly compatible with the polymeric material of the core. Polymeric materials suitable for the core include, for example, polyethylene terephthalate (PET), polyimide, and soft epoxy. Alternatively, the adhesion layer or undercoat layer may be an organotitanium or organodecane compound. A mixture containing a resin as a main component can also be used. In addition to the inherent incorporation of the core material, the adhesion layer or primer layer acts as a rust resistant layer capable of avoiding oxidation of the thin layer of copper. For better adhesion of the primer layer, an adhesive tape can be attached at the same time as the primer.

A substrate produced in accordance with a specific embodiment of the present invention can be used as a printed circuit board The materials, and more specifically, are used in the manufacture of multilayer printed circuit boards. The method of manufacturing a multilayer printed circuit board according to the prior art and according to an embodiment of the present invention will be successively described.

Figure 3 is a view showing the manufacturing method of the prior art multilayer printed circuit board flow chart. Referring to Fig. 3, a flexible copper clad laminate (FCCL) is cut into a predetermined size (S1). In the soft copper clad laminate, the copper film is bonded to a polyimine core. Subsequently, the cut flexible copper clad laminate film is etched to form an internal circuit (S2) thereon, and then a protective layer is bonded thereto (S3). Subsequently, another soft copper clad laminate is laminated on the protective layer through a bonding sheet (S4). Subsequently, copper plating is performed on the laminated soft copper-clad laminate to form a copper plating layer (S5), and then the copper plating layer is drilled to form a plurality of through holes (S6). Subsequently, the residue remaining on the inner wall of the through hole after processing, for example, debris (S7), is removed by a desmear process. Subsequently, electroless copper plating and copper plating are sequentially performed to form a copper plating layer (S8 and S9). Subsequently, etching is performed on the copper plating layer to form an external circuit (S10), and then a printing process is performed on the external circuit to form a PSR printed layer (S11).

According to the conventional manufacturing method, the use of the soft copper clad laminate includes complicated The expensive copper film causes an increase in cost, and the complicated lamination procedure and increased use of auxiliary materials increase the thickness of the multilayer printed circuit board. In contrast, the use of a substrate according to the present invention in a simplified, economical manner in the manufacture of a multilayer printed circuit board is efficient. The method of manufacturing a multilayer printed circuit board according to the present invention will be described in detail.

Figure 4 is a diagram illustrating a printed circuit board in accordance with an embodiment of the present invention. A flow chart of the manufacturing method. Referring to Fig. 4, first, a substrate produced by the method described with reference to Fig. 2 is used as a soft copper clad laminate and is cut to a predetermined size (S1). Subsequently, the cut substrate is selectively drilled to form a plurality of through holes (S2). Subsequently, the inner wall of the through hole is treated with a conductive polymer or electroless copper. The conductive polymer treated or electroless copper is a pretreatment process for plating (S3). Subsequently, a dry film is laminated on the substrate, exposed to form a positive image, and developed (S4). Subsequently, the pretreated substrate is subjected to copper plating to form a thin copper layer (S5). Subsequently, after the circuit is formed by copper plating, the remaining dry film is peeled off (S6). Subsequently, the copper thin layer remaining on the underlying layer of the portion where the dry film has been peeled off is etched (S7). Subsequently, a cover layer is laid to a portion other than the exposed circuit (S8).

According to a printed circuit board made using a substrate produced according to a specific embodiment of the present invention In the method of fabrication, only portions for circuit formation are exposed and filled with plating material to form an electrical circuit. In contrast, according to the conventional manufacturing method, the entire area of one panel is plated with copper, and portions other than the circuit formation are etched. Therefore, the manufacturing method according to the embodiment of the present invention is very economical and suitable for the formation of fine circuits. In particular, with the recent trend in technology, there is an increasing demand for fine circuits, which has been difficult to achieve by conventional etching procedures. In this case, it is important to develop a semi-additive method of filling a circuit portion with a plating material.

Here, a manufacturing method according to an embodiment of the present invention, which is described with reference to FIG. 4, The use of a polyimine core is described in more detail. First, using the actual implementation according to the present invention The copper clad laminate of the substrate produced by the example was cut to a predetermined size. Subsequently, the cut copper clad laminate is selectively processed to form a hole. Circuits formed on both sides of the substrate are in electrical communication with each other through the holes. The holes are typically formed by machining, using CNC drilling or laser drilling. Alternatively, the pores can be formed by chemical processing using a polyimide etchant. The aluminum carrier used in the specific embodiment of the present invention can be used as an entry board. In the procedure of using a drill, it is advantageous to improve the positional accuracy of the hole and to dissipate heat. This hole machining can also be omitted. After the drilling process, the aluminum carrier is separated from the thin layer of copper. A physical or chemical process can be used to separate the aluminum support and the thin layer of copper. Aluminum and copper are dissimilar metals and are therefore easy to separate. Accordingly, a physical method can generally be used to separate the aluminum support and the thin layer of copper. In the case of a material having a polyimine as a core, it is bonded to the copper thin layer at a high temperature of about 350 ° C or higher, and diffusion occurs between the carrier aluminum and the copper thin layer, so that It is difficult to peel evenly between them. In this case, a method is needed to use a suitable chemical such as sodium hydroxide to remove only aluminum. According to the present invention, since the porous layer is formed on the surface of the aluminum support, the thickness of the intrinsic alumina or aluminum hydroxide can be ignored. Accordingly, it is advantageous to remove the aluminum carrier using only one aluminum etching solution. Subsequently, the resulting structure is treated with a conductive polymer or electroless copper. This processing or plating is a procedure for forming a conductive layer on the inner walls of the holes to allow current to flow through the holes. Since the aluminum carrier has been removed from the copper foil laminate, the inner wall of the hole-processed portion of the copper foil laminate is composed of a non-conductive polyimide, so that the conductive layer is formed. In addition to the treatment using a conductive polymer or electroless copper plating, other procedures such as a black hole using a carbon particle and a shadow program can be applied. After the conductive polymer treatment or electroless copper plating, chemical copper plating or direct copper plating may be further performed on the conductive layer. A dry film is then attached to the electrically conductive substrate, exposed to form a positive image, and developed. Subsequently, the exposed portion for circuit formation is plated with copper to form an electrical circuit, and then the remaining dry film is peeled off. Subsequently, the thin copper foil remaining on a portion of the base layer is etched. Subsequently, a cover layer is laid out to the portion other than the circuit to complete the manufacture of the printed circuit board.

The invention will be explained in more detail with reference to the following examples.

Example

(1) Degreasing of aluminum carrier surface (cleaning and formation of porous layer)

An aluminum support was degreased using a diluted degreaser (Al clean 193, YMT) and allowed to stand at 30-50 ° C for 2-5 minutes to remove contaminants such as: organic matter from its surface. Thereby, the surface of the aluminum carrier is partially etched to form a porous layer.

(2) Formation of chromium-polymer layer (sealing layer)

A thin chromium (Cr)-polymer film is formed on the degreased aluminum (on the porous layer). The formation of the chromium-polymer film facilitates separation between a thin layer of copper and the underlying aluminum layer. The chromium-polymer film is immersed in a chromium at 50-70 ° C ( 1 wt%) of the acidic aqueous solution was post-treated for 10-15 minutes. The acidic aqueous solution is CrF ₃ . A mixture of 3H ₂ O and polyethylene glycol (PEG).

(3) Copper plating

The electroless copper is applied to the chromium-polymer layer at 30-50 ° C for 5-15 minutes. The thickness of the copper layer is adjusted by increasing or decreasing the plating time.

(4) Resin coating (formation of adhesion layer)

The copper-plated aluminum carrier is used to manufacture a copper clad laminate. To achieve this, a resin is applied to the surface of the copper thin layer to have a thickness of about 7 to 9 μm. Polyethylene (PE) or epoxy resin is used as a resin depending on the substrate to be laminated in the subsequent step. The resin coated structure was dried in an oven at 80-100 ° C for at least 5 minutes to remove the solvent present in the resin.

(5) cascading (core bonding)

The resin coated structure is laminated to an underlying substrate such as PET, PEN, PI or Pre-preg depending on the desired application. When the substrate is a soft material, a roll-to-roll process is used, and when the substrate is rigid, the system is made Use a hot pressing procedure.

(6) Removal of aluminum carrier

This unnecessary aluminum carrier is removed from the laminate structure. The peel strength of the aluminum support is not higher than 100 gf/cm due to the presence of the release layer formed in (2).

Evaluation example

The peel strength of the carrier and the copper layer was measured by a 90 peel test.

The peeling strength of about 300 gf/cm of the comparative product was exhibited without one of the separation inducing layers, and about 100 gf/cm between the thin layer of copper and the carrier was found in the product formed after the separation inducing layer was treated at about 30 ° C for 3 minutes. Or less peel strength. These results show the presence of the copper foil inducing layer which promotes the peeling of the copper thin layer from the carrier after the transfer of the copper thin layer.

The difference in peel strength between the copper thin layer and the support depends on the surface roughness of the support. When the carrier is etched by using an etching solution of a basic compound for about 0.1 μm, a surface roughness (Ra) of about 1.5 to 2.0 is obtained. When the carrier is finely etched by about 0.1 μm using an etching solution containing a corrosion inhibitor as a functional additive, a surface roughness (Ra) of about 0.4 to 0.5 is obtained.

The surface roughness of the aluminum carrier decreases as the thickness decreases. Accordingly, the electroless copper reduces the peel strength between the carrier and the copper thin layer from about 300 gf/cm to about 200 gf/cm, making it easier to peel off from each other.

Although the technical idea of the present invention has been disclosed with reference to the specific embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the essential features of the invention. Therefore, the specific embodiments are merely illustrative and should not be construed as limiting the technical idea of the invention. The technical scope of the present invention is defined by the scope of the appended claims, and all technical ideas falling within the scope of the claims are intended to fall within the scope of the invention.

S1‧‧‧Step one

S2‧‧‧Step 2

S3‧‧‧Step three

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S5‧‧‧Step five

S6‧‧‧Step six

S7‧‧‧Step seven

S8‧‧‧Step eight

Claims (8)

A method for producing a substrate having a thin layer of copper, the method comprising: providing a carrier; forming a separation inducing layer on a surface of the carrier; forming a thin layer of copper on the separation inducing layer; and combining a core To the copper thin layer, wherein the carrier is composed of aluminum, and the separation inducing layer is formed by forming a porous layer on the surface of the carrier and coating a surface of the carrier having the porous layer with a sealant. . The method of claim 1, wherein the porous layer is formed on the surface of the support using a solvent comprising at least one compound selected from the group consisting of a basic compound, an iron compound, and a carbonic acid compound. The method of claim 1, wherein the porous layer is formed on the surface of the support by electroless etching. The method of claim 1, wherein the porous layer is formed on a surface of a support comprising aluminum. The method of claim 1, wherein the sealant applied to the surface of the carrier having the porous layer comprises at least one material selected from the group consisting of cobalt-chromium, metal-polymer composites, boron nitride, and A group consisting of molybdenum sulfide and polytetrafluoroethylene. A method of manufacturing a printed circuit board, comprising: providing a substrate having a thin layer of copper produced by the method of claim 1; separating the carrier and the separation inducing layer from the substrate ; Forming a mask for patterning on the copper thin layer and forming a copper pattern by plating on the copper thin layer; removing the mask for pattern formation; and removing the copper thin layer to leave The next patterned copper circuit. A printed circuit board manufactured by the method of claim 6 of the patent application. A substrate comprising: a carrier made of aluminum; a separation inducing layer formed on the surface of the carrier; a thin layer of copper formed on the separation inducing layer; and a core a core bonded to the copper thin layer, wherein the separation inducing layer is composed of a porous aluminum layer and a sealing layer formed on the porous aluminum layer.