Ultra-thin copper foil with carrier foil for easy micro-hole processing, copper foil laminate including same, and method for manufacturing same

Abstract

The present invention provides an ultra-thin copper foil with a carrier foil, which is formed by sequentially laminating a carrier foil, a release layer, and an ultra-thin copper foil, and the carrier foil includes a surface treatment layer on the surface facing the release layer.

Description

[Technical Field]

[0001] The present invention relates to an ultra-thin copper foil with a carrier foil and a copper foil laminate using the same. [Background technology]

[0002] An ultra-thin copper foil with a carrier foil is formed by sequentially forming a release layer and an ultra-thin copper foil by electrolytic copper plating on one side of a carrier foil, and generally, the outermost surface of the copper-plated ultra-thin copper foil is finished as a roughened surface.

[0003] A printed wiring board using an ultra-thin copper foil with a carrier foil may be manufactured as follows: First, an ultra-thin copper foil with a carrier foil is placed on the surface of an insulating substrate made of resin or the like, and then heated and pressed to manufacture a copper foil laminate. Next, the manufactured laminate is subjected to through-hole formation and through-hole plating in order to form plated through-holes. After that, the copper foil on the surface of the laminate is etched to form a wiring pattern with the required line width and line pitch. Finally, solder resist is formed and other processes are performed.

[0004] Meanwhile, in recent years, a printed wiring board, particularly a build-up wiring board, has been produced by first adhering the roughened surface of copper foil to an adhesive resin such as epoxy resin, and then using the adhesive resin as a semi-cured (B-stage) insulating resin layer. The resin-coated copper foil is then used as the copper foil for forming surface circuits, and the insulating resin layer is then thermocompressed onto an insulating substrate. Such build-up wiring boards require high integration of various electronic components, and correspondingly, high-density wiring patterns are also required. This necessitates wiring patterns with fine line widths and line-to-line pitches, i.e., fine-pattern printed wiring boards. For example, high-density printed wiring boards with line widths and line-to-line pitches of approximately 20 μm each are required. For the formation of via holes in build-up wiring boards, the laser via method using a CO gas laser is primarily used due to its high productivity. However, when using a CO2 gas laser with conventional ultra-thin copper foil carrier foil, the wavelength of the CO2 gas laser is in the infrared range of around 10,600 nm, and the copper foil surface largely reflects light in this range, making it impossible to directly process via holes. Instead, a conformal mask method is used, in which the copper foil in the area where the via holes are to be formed is first etched and removed, and then via holes are processed in the substrate. However, with the conformal mask method, the etching resist is not applied to the area of ​​the ultra-thin copper foil where the via holes are to be formed, while the etching resist is applied to other areas. This results in a complex process in which the ultra-thin copper foil is first etched and then via holes are processed in the substrate (resin portion) with a CO2 gas laser. Therefore, if via holes could be processed simultaneously in the ultra-thin copper foil and the resin portion using a CO2 gas laser, the via hole processing process could be simplified.

[0005] For this reason, there is a demand for carrier foil ultra-thin copper foil that has low reflectivity to CO2 gas laser when processing through holes or via holes in carrier foil-attached ultra-thin copper foil or copper foil laminates containing the same, and that can simultaneously process via holes in the ultra-thin copper foil and resin.

[0006] Therefore, Korean Patent Publication No. 2013-82320 provides an ultra-thin copper foil with a carrier foil, in which the release layer is made of a metal alloy layer with a specific content including a first metal, a second metal that facilitates plating of the first metal, and a third metal. However, even when via holes are drilled in such an ultra-thin copper foil with a CO2 laser, the copper foil surface still reflects a significant portion of the laser light, limiting efficient via hole drilling. Summary of the Invention [Problem to be solved by the invention]

[0007] In order to solve the above-mentioned problems of the conventional technology, the present invention aims to provide an ultra-thin copper foil with a carrier foil having a new structure that allows easy laser hole processing, and a manufacturing method thereof.

[0008] Another object of the present invention is to provide an ultra-thin copper foil with a carrier foil that has excellent penetration processability with a CO2 laser, and a method for producing the same.

[0009] Another object of the present invention is to provide a copper foil laminate comprising the above-mentioned ultra-thin copper foil with a carrier foil. [Means for solving the problem]

[0010] In order to achieve the above technical objectives, the present invention provides an ultra-thin copper foil with a carrier foil, in which a carrier foil, a release layer, and an ultra-thin copper foil are laminated in this order, and the carrier foil includes a surface treatment layer on the surface facing the release layer.

[0011] In the present invention, the surface treatment layer may have a surface structure in which protrusions having an average diameter of 10 μm or less are arranged. In this case, the surface treatment layer may have a surface structure in which protrusions having an average diameter of 2 μm or less are arranged.

[0012] In the present invention, the protrusions are 8,000 to 10,000 per mm 2 The surface area density may be 0.015 μm or less.

[0013] In the present invention, the protrusions may be formed by etching the surface of the carrier foil.

[0014] In the present invention, the ultrathin copper foil with a carrier foil may have a surface structure formed on the S-side of the ultrathin copper foil after peeling, in which grooves having an average diameter of 10 μm or less are arranged.

[0015] In the present invention, the ultrathin copper foil with a carrier foil may have a surface structure formed on the S-side of the ultrathin copper foil after peeling, in which grooves having an average diameter of 2 μm or less are arranged.

[0016] At this time, the grooves of the surface structure are 8,000 to 10,000 / mm 2 The density may be

[0017] In the present invention, the S-side of the peeled ultra-thin copper foil may contain Ni and P.

[0018] The present invention may further include a laser absorbing layer between the release layer and the ultrathin copper foil, the laser absorbing layer containing Cu and at least one metal selected from the group consisting of Ni, Co, Fe, Pb, and Sn, or an alloy thereof.

[0019] The ultrathin copper foil with a carrier foil of the present invention may further include a diffusion prevention layer between the carrier foil and the release layer. Also, the ultrathin copper foil with a carrier foil of the present invention may further include a heat-resistant layer between the release layer and the ultrathin copper foil.

[0020] In order to achieve the above-mentioned other technical object, the present invention also provides a copper foil laminate obtained by laminating the above-mentioned ultra-thin copper foil with a carrier foil on a resin substrate.

[0021] In order to achieve the above-mentioned still other technical object, the present invention provides a method for manufacturing an ultra-thin copper foil with a carrier foil, comprising the steps of forming a laminated structure of a carrier foil, a release layer, and an ultra-thin copper foil, wherein the laminated layer structure comprises the steps of: providing a carrier foil; etching one side of the carrier foil to form a surface treatment layer; and sequentially forming a release layer and an ultra-thin copper foil on the surface treatment layer.

[0022] In the present invention, the etching solution for the etching treatment may be prepared using one or more organic agents selected from sulfuric acid, hydrogen peroxide, sodium hydroxide, nitrogen-containing organic compounds, and sulfur-containing organic compounds. Examples of the nitrogen-containing organic compounds include 1,2,3-benzotriazole and carboxybenzotriazole, and examples of the sulfur-containing organic compounds include mercaptobenzothiazole and thiocyanuric acid. [Effects of the Invention]

[0023] The present invention makes it possible to provide an ultra-thin copper foil with a carrier foil having a new structure that facilitates laser hole processing, and also makes it possible to provide an ultra-thin copper foil with a carrier foil that has precise and excellent penetration processability with a CO2 laser, and a copper foil laminate including the same. [Brief explanation of the drawings]

[0024] [Figure 1A] 1 is a diagram showing a schematic diagram of a laminated structure of an ultra-thin copper foil with a carrier foil according to an embodiment of the present invention. [Figure 1B] 1 is a diagram showing a schematic diagram of a laminated structure of an ultra-thin copper foil with a carrier foil according to an embodiment of the present invention.

[0025] [Figure 2A] 1 is an electron microscope photograph of the surface of a carrier foil according to an embodiment of the present invention. [Figure 2B] 1 is an electron microscope photograph of the surface of a carrier foil according to an embodiment of the present invention.

[0026] [Figure 3A] 1 is an electron microscope photograph of the surface of a copper foil after peeling off the carrier foil from a carrier foil-attached ultrathin copper foil specimen manufactured according to an embodiment of the present invention. [Figure 3B] 1 is an electron microscope photograph of the surface of a copper foil after peeling off the carrier foil from a carrier foil-attached ultrathin copper foil specimen manufactured according to an embodiment of the present invention.

[0027] [Figure 4A] 1 is an electron microscope photograph taken after laser through-hole processing of an ultra-thin copper foil specimen with a carrier foil manufactured according to an embodiment of the present invention. [Figure 4B] 1 is an electron microscope photograph taken after laser through-hole processing of an ultra-thin copper foil specimen with a carrier foil manufactured according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] The embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so it should be understood that there may be various equivalents and modifications that can be substituted therefor. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0029] In the present specification, the term "lamination" means bonding at least two or more layers together. For example, lamination of a first layer and a second layer includes not only direct contact between the first and second layers, but also bonding the first and second layers together with an additional third layer sandwiched between them. Furthermore, in the laminate structure of the present invention, the presence of a third layer between the first and second layers includes both a state in which the third layer is in direct contact with the first and second layers and a state in which the third layer is not in direct contact with the first or second layer.

[0030] 1A and 1B are diagrams each showing a schematic view of a laminate structure of an ultra-thin copper foil with a carrier foil according to one embodiment of the present invention.

[0031] First, referring to FIG. 1A, the ultra-thin copper foil with a carrier foil has a structure in which a carrier foil 100, a surface treatment layer 110, a diffusion prevention layer 120, a release layer 130, a heat-resistant layer 140, and an ultra-thin copper foil 150 are laminated in order.

[0032] The carrier foil 100 serves as a support (carrier) until the ultra-thin copper foil is bonded to an insulating substrate. The carrier foil can be aluminum foil, stainless steel foil, titanium foil, copper foil, or copper alloy foil. For example, electrolytic copper foil, electrolytic copper alloy foil, rolled copper foil, or rolled copper alloy foil can be used. Preferably, the carrier foil is electrolytic copper foil, and the upper surface 100B of the carrier foil can be either a glossy or matte surface. A roughened layer can be formed on the lower surface 100A of the carrier foil.

[0033] The carrier foil may have a thickness of 1 mm or less. For example, the thickness of the carrier foil may be 7 to 70 μm. For example, the thickness of the carrier foil may be 12 to 18 μm. If the thickness of the carrier foil is less than 7 μm, it will be difficult for the carrier foil to function as a carrier. If the thickness of the carrier foil is more than 1 mm, the carrier foil will function as a carrier without any problems, but when continuous plating is performed to form a release layer, an ultra-thin copper foil, etc., the foil tension in the continuous plating line must be increased, which may require large-scale equipment.

[0034] In the present invention, a surface treatment layer 110 is added between the carrier foil 100 and the diffusion prevention layer 120 or to the interface between the carrier foil 100 and the diffusion prevention layer 120. In the present invention, the surface treatment layer 110 has a structure in which fine protrusions having an average diameter of 10 μm or less, 5 μm or less, 2 μm or less, or 1 μm or less are arranged. In the present invention, the average diameter of the fine protrusions is preferably 0.5 μm or more.

[0035] In the present invention, the area density of the fine protrusions is 8,000 to 10,000 / mm 2 It is preferable that:

[0036] Thus, in the present invention, the surface treatment layer has fine protrusions having a wavelength of CO2 laser or less (e.g., 10,600 nm), and as will be described later, the fine grooves formed after peeling in correspondence with these fine protrusions can scatter the laser light and promote the absorption of the laser light.

[0037] Furthermore, in the present invention, the surface treatment layer 110 can be regarded as a smooth surface with low roughness, and the electrode foil 150 subsequently formed thereon can also have a surface with low roughness. In the present invention, the surface treatment layer 110 preferably has a surface roughness of 0.5 to 1.5 μm.

[0038] Preferably, in the present invention, the surface treatment layer 110 may be formed by etching the surface of the carrier foil 100. For example, the surface treatment layer 110 may be formed by treating the surface of the carrier foil 100 with an etching solution containing sulfuric acid, hydrogen peroxide, sodium hydroxide, and at least one type of BTA (benzotriazole).

[0039] In the present invention, the diffusion barrier layer 120 and the heat-resistant layer 140 may contain one or more elements selected from the group consisting of Ni, Co, Fe, Cr, Mo, W, Al, and P. For example, the diffusion barrier layer and the heat-resistant layer may be a single metal layer, an alloy layer of two or more metals, or a layer of one or more metal oxides.

[0040] For example, plating to form a single metal layer may be nickel plating, cobalt plating, iron plating, aluminum plating, etc. Plating to form a binary alloy layer may be nickel-cobalt plating, nickel-iron plating, nickel-chromium plating, nickel-molybdenum plating, nickel-tungsten plating, nickel-copper plating, nickel-phosphorus plating, cobalt-iron plating, cobalt-chromium plating, cobalt-molybdenum plating, cobalt-tungsten plating, cobalt-copper plating, cobalt-phosphorus plating, etc. The plating that forms a ternary alloy layer is nickel-cobalt-iron plating, nickel-cobalt-chromium plating, nickel-cobalt-molybdenum plating, nickel-cobalt-tungsten plating, nickel-cobalt-copper plating, nickel-cobalt-phosphorus plating, nickel-iron-chromium plating, nickel-iron-molybdenum plating, nickel-iron-tungsten plating, nickel-iron-copper plating, nickel-iron-phosphorus plating, nickel-chromium-molybdenum plating, nickel-chromium-tungsten plating, nickel-chromium-copper plating, nickel-chromium-phosphorus plating, nickel-molybdenum-tungsten plating, nickel-molybdenum-copper plating, nickel-molybdenum Cobalt-iron-phosphorus plating, nickel-tungsten-copper plating, nickel-tungsten-phosphorus plating, nickel-copper-phosphorus plating, cobalt-iron-chromium plating, cobalt-iron-molybdenum plating, cobalt-iron-tungsten plating, cobalt-iron-copper plating, cobalt-iron-phosphorus plating, cobalt-chromium-molybdenum plating, cobalt-chromium-tungsten plating, cobalt-chromium-copper plating, cobalt-chromium-phosphorus plating, cobalt-molybdenum-phosphorus plating, cobalt-tungsten-copper plating, cobalt-tungsten-phosphorus plating, cobalt-copper-phosphorus plating, and the like may be used.

[0041] Preferably, the diffusion prevention layer 120 and the heat-resistant layer 140 may contain Ni and P.

[0042] The diffusion barrier layer 120 prevents copper from diffusing into the release layer when the carrier foil-attached ultra-thin copper foil is pressed against an insulating substrate at high temperatures. The diffusion of copper into the release layer can create a metallic bond between the carrier foil and the ultra-thin copper foil, and the strong bonding force can make it difficult to peel the carrier foil. The diffusion barrier layer 120 can prevent this reaction.

[0043] In the copper foil with carrier foil, the release layer 130 is a layer for improving the peelability when peeling the ultra-thin copper foil from the carrier foil, and is introduced to peel the carrier foil cleanly and easily. The release layer is removed together with the carrier foil.

[0044] In the present invention, the release layer 130 may include a metal or metal alloy having release properties. The release metal may include molybdenum or tungsten. The release layer 130 may also include a plating catalyst. For example, the release layer 130 may include at least one metal selected from the group consisting of Fe, Co, and Ni.

[0045] The release layer may be an organic release layer having releasability, for example, the release layer may contain at least one organic material selected from the group consisting of BTA series.

[0046] The ultra-thin copper foil 150 may have a thickness of 12 μm or less, and preferably has a thickness of 1.5 to 5 μm.

[0047] In the present invention, the ultrathin copper foil preferably has a surface roughness (Rz) of 0.5 to 1.5 μm.

[0048] Ultra-thin copper foils may have a roughened surface and a non-roughened surface depending on the application. The roughened surface may be formed by a nodulation process, and the non-roughened surface may be formed by adding a brightener and a suppressor during the formation of the copper foil.

[0049] In the present invention, the surface of the ultrathin copper foil may be further surface-treated, for example, by heat and chemical resistance treatment, chromate treatment, silane coupling treatment, or a combination thereof, and the type of surface treatment to be performed may be appropriately selected depending on the subsequent process.

[0050] The heat and chemical resistance treatment can be performed by forming a thin film of any one of metals such as nickel, tin, zinc, chromium, molybdenum, and cobalt, or an alloy thereof, on the metal foil by sputtering, electroplating, or electroless plating. From the viewpoint of cost, electroplating is preferred.

[0051] For the chromate treatment, an aqueous solution containing hexavalent to trivalent chromium ions can be used. The chromate treatment can be a simple immersion treatment, but is preferably carried out by cathodic treatment. For example, cathodic treatment can be carried out in a solution of 0.1 to 70 g / L of sodium dichromate, pH 1 to 13, bath temperature 15 to 60°C, and current density 0.1 to 5 A / dm 2 It is preferable to carry out the electrolysis for 0.1 to 100 seconds. It is also preferable to carry out the chromate treatment on top of the rust prevention treatment, which can further improve the moisture resistance and heat resistance.

[0052] The silane coupling agent used in the silane coupling treatment may be one or more substances or mixtures selected from the group consisting of epoxy-functional silanes such as 3-glycidoxypropyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, amino-functional silanes, olefin-functional silanes, acryl-functional silanes, methacryl-functional silanes, and mercapto-functional silanes. For example, the silane coupling agent may be dissolved in a solvent such as water at a concentration of 0.1 to 15 g / L and applied to a metal foil at room temperature to 70°C or electrodeposited thereon. After the silane coupling treatment, a stable bond can be formed by heating, ultraviolet irradiation, or the like. Heating may be performed at a temperature of 100 to 200°C for 2 to 60 seconds.

[0053] Another embodiment of the present invention will now be described with reference to FIG. 1B.

[0054] The ultra-thin copper foil with carrier foil shown in FIG. 1B differs from that shown in FIG. 1A in that it further includes a laser absorbing layer 160 between the release layer 130 and the heat-resistant layer 140 .

[0055] The laser absorbing layer 160 is a low-gloss, dark-colored plating layer. For example, the laser absorbing layer 160 may contain Cu and at least one metal selected from the group consisting of Ni, Co, Fe, Pb, and Sn or an alloy thereof, such as one, two, or three metals or alloys thereof.

[0056] In the present invention, the thickness of the laser absorbing layer 160 is preferably 0.01 to 1 μm. More preferably, the thickness of the laser absorbing layer 160 may be 0.05 to 0.5 μm. If the thickness is 0.05 μm, the absorbing layer has almost no effect on the color change, but if the thickness is 1 μm or more, the color may be too dark and the laser may penetrate during laser processing, which may result in defects.

[0057] The ultra-thin copper foil with carrier foil shown in FIG. 1B can exhibit higher laser absorption by adding the laser absorbing layer 160. [Example]

[0058] The present invention will be described in more detail below with reference to examples, which are merely presented as preferred examples of the present invention and are not to be construed as limiting the present invention in any way.

[0059] Example 1

[0060] The laminated structure was formed in the following order.

[0061] [A. Carrier foil]

[0062] An electrolytic copper foil having a surface roughness (Rz) of 1.2 μm on the shiny side and a thickness of 18 μm was immersed in 100 g / L of sulfuric acid for 5 seconds, and after pickling treatment, was washed with pure water.

[0063] [B. Surface treatment layer]

[0064] The surface of the carrier foil was pretreated and activated with the following pretreatment solution.

[0065] a. One or more organic agents selected from sulfuric acid: 200 to 300 g / L, hydrogen peroxide: 50 to 150 g / L, nitrogen-containing organic compounds, and sulfur-containing organic compounds are used.

[0066] b.Temperature: 40℃

[0067] c. pH: 0.01 to 0.5

[0068] d. Soaking time: 5 seconds

[0069] [C. Diffusion prevention layer]

[0070] A diffusion barrier layer was formed by Ni-P plating under the following plating conditions.

[0071] a.Ni concentration: 10~20g / L, P concentration 5~15g / L

[0072] b.pH: 4.0, temperature: 30℃, current density: 1.5A / dm 2 , Plating time: 2 seconds

[0073] The amount of adhesion of the formed diffusion prevention layer is 301 μg / dm 2 It was.

[0074] [D. Release Layer]

[0075] A peeling layer was formed by plating Mo-Ni-Fe under the following plating conditions.

[0076] a. Mo concentration: 10-30 g / L, Ni concentration: 3-10 g / L, Fe concentration: 1-7 g / L, sodium citrate: 100-200 g / L, pH: 10.2 (ammonia water 30 ml / L added)

[0077] b. Temperature: 30℃, current density: 10A / dm 2 , Plating time: 7 seconds

[0078] The adhesion weight of the formed peeling layer was 1.01 mg / dm 2 The composition of the release layer was 62.31 wt % Mo, 30.8 wt % Ni, and 6.89 wt % Fe.

[0079] [E.Heat-resistant layer]

[0080] The heat-resistant layer was formed by Ni-P plating under the following plating conditions.

[0081] a.Ni concentration: 10~20g / L, P concentration 5~15g / L, pH: 4.0

[0082] b. Temperature: 30℃, current density: 1.5A / dm 2 , Plating time: 2 seconds

[0083] The amount of adhesion of the formed diffusion prevention layer is 301 μg / dm 2 It was.

[0084] [F. Copper foil]

[0085] Copper foil with a thickness of 2 μm was formed under the following plating conditions:

[0086] a.CuSO4-5H2O:300g / L, H2SO4:150g / L

[0087] b. Temperature: 35℃, current density: 20A / dm 2 , Plating time: 30 seconds

[0088] [G. Additional Processing]

[0089] The surface of the electrode copper foil was further subjected to heat and chemical resistance treatment, chromate treatment, and silane coupling treatment.

[0090] <Example 2>

[0091] An ultra-thin copper foil with a carrier foil was manufactured in the same manner as in Example 1, except that a laser absorbing layer was added between the release layer and the heat-resistant layer. The laser absorbing layer was formed by plating under the following conditions.

[0092] a. Copper concentration: 1-5 g / L, nickel concentration: 1-5 g / L, cobalt concentration: 1-10 g / L, ammonium sulfate: 10-50 g / L, sodium citrate: 30-70 g / L

[0093] b.pH: 4.5, temperature: 30℃, current density: 20A / dm 2 , Plating time: 4 seconds

[0094] Example 3

[0095] An ultrathin copper foil with a carrier foil was produced in the same manner as in Example 2, except that an organic release layer was formed as the release layer. The organic release layer was formed by plating under the following conditions.

[0096] a. Carboxybenzotriazole concentration: 1-5 g / L, copper concentration: 5-15 g / L, H2SO4 concentration: 150 g / L

[0097] b. Temperature: 40℃, immersion time: 30 seconds

[0098] <Comparative Example 1>

[0099] An ultrathin copper foil with a carrier foil was produced in the same manner as in Example 1, except that the surface treatment layer was omitted.

[0100] <Comparative Example 2>

[0101] An ultrathin copper foil with a carrier foil was produced in the same manner as in Example 2, except that the surface treatment layer was omitted.

[0102] <Experimental Example>

[0103] The surface roughness (Rz) of the carrier foil-attached ultrathin copper foil specimens manufactured in Examples 1 to 3 and Comparative Example 1 and Comparative Example was measured. In addition, the manufactured specimens were peeled off, and the gloss and color of the peeled surface (S-side) were measured. The measurement conditions for surface roughness, gloss, and color were as follows:

[0104] a.Surface roughness

[0105] Measuring equipment: SURFCOM 1400D (TSK, Tokyo Seimitsu)

[0106] Measurement standard: Measured according to IPC-TM-650 standard

[0107] b. Glossiness

[0108] Measurement equipment: Gloss Metal VG7000, NIPPON DENSHOKU

[0109] Measurement standard: Gs (60°), JIS Z871-1997

[0110] c.Color

[0111] Measurement equipment: CM-2500d, KONIKA MINOLTA

[0112] Measurement standards: SCE, L* measurement

[0113] The laser processability of the carrier foil-attached ultrathin copper foil specimens manufactured in Examples 1 to 3 and Comparative Example 1 and Comparative Example was evaluated. The laser processing conditions were as follows.

[0114] d. Laser processability evaluation

[0115] After peeling off the manufactured ultrathin copper foil with the carrier foil, the obtained ultrathin copper foil specimen was subjected to one-shot processing using a carbon dioxide gas laser via hole processing machine, using a beam for processing a 30 μm hole size, and measuring the size of the via hole formed in the copper foil at laser powers of 7 W and 5 W. The laser processing equipment used was a Hitachi LC-4K series laser drilling machine.

[0116] Table 1 below summarizes the evaluation results for surface roughness, gloss, color, and laser processability.

[0117] [Table 1]

[0118] From Table 1, it can be seen that in Example 1, in which a surface treatment layer was formed on the surface of the carrier foil, the S-side gloss of the peeled electrode foil was lower and the hole size by the CO2 laser was larger than in Comparative Example 1, in which no surface treatment layer was formed. On the other hand, in Examples 2 and 3, in which both a surface treatment layer and a laser absorbing layer were formed, the difference in gloss and color was more noticeable compared to Example 1, and the laser hole size was larger.

[0119] 2A and 2B are electron microscope photographs of the carrier foil surface before and after the formation of the surface treatment layer during the manufacturing process of Example 1, respectively.

[0120] This photograph shows that the surface treatment has resulted in the development of a protruding structure on the surface.

[0121] 3A and 3B are electron microscope photographs of the S-side of the ultra-thin copper foils peeled from the specimens of Comparative Example 1 and Example 2, respectively.

[0122] This photograph shows that Comparative Example 1, which does not have a surface treatment layer, shows the same condition as the carrier foil surface, while Example 2 shows an intaglio structure with an array of multiple recessed grooves with an average diameter of 2 μm or less. It can be seen that this structure substantially corresponds to the surface relief structure in Figure 2B.

[0123] 4A and 4B are electron microscope photographs of through holes after laser processing of specimens manufactured according to Example 2 and Comparative Example 1, respectively. As can be seen from the figures, holes with larger opening diameters were formed in the specimens of the examples compared to the comparative examples at the same laser power. These results indicate that the ultra-thin copper foil with a carrier foil having a laminated structure of the present invention enables the formation of via holes or through holes with wider diameters in a shorter time than conventional methods.

[0124] Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will recognize that various modifications can be made to the above-described embodiments without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the appended claims and equivalents thereof. [Industrial Applicability]

[0125] The present invention is applicable to a copper foil with a carrier foil and a copper foil laminate using the same.

Claims

1. An ultra-thin copper foil with a carrier foil in which a carrier foil, a release layer and an ultra-thin copper foil are laminated in this order, the carrier foil includes a surface treatment layer on the surface facing the release layer; the surface treatment layer has a surface structure in which protrusions with an average diameter of 10 μm or less are arranged, The ultra-thin copper foil with a carrier foil is characterized in that the protrusions have an area density of 8,000 to 10,000 protrusions / mm 2 .

2. The ultra-thin copper foil with a carrier foil according to claim 1, wherein the surface treatment layer has a surface structure in which protrusions having an average diameter of 2 μm or less are arranged.

3. The ultra-thin copper foil with a carrier foil according to claim 1 or 2, wherein the protrusions are formed by etching the surface of the carrier foil.

4. The ultra-thin copper foil with a carrier foil according to claim 1, characterized in that after peeling, a surface structure in which holes with an average diameter of 10 μm or less are arranged on the S-side of the ultra-thin copper foil is formed.

5. The ultra-thin copper foil with a carrier foil according to claim 1, characterized in that after peeling, a surface structure in which holes with an average diameter of 2 μm or less are arranged on the S-side of the ultra-thin copper foil is formed.

6. The number of holes is 8,000 to 10,000 per mm ２ The ultra-thin copper foil with a carrier foil according to claim 4 or 5, characterized in that it has a density of

7. The ultra-thin copper foil with a carrier foil according to claim 4 or 5, wherein the S-side of the peeled ultra-thin copper foil contains Ni and P.

8. Between the release layer and the ultra-thin copper foil, 2. The carrier foil-attached ultra-thin copper foil according to claim 1, further comprising a laser absorbing layer containing Cu and at least one metal selected from the group consisting of Ni, Co, Fe, Pb, and Sn, or an alloy thereof.

9. The ultra-thin copper foil with a carrier foil according to any one of claims 1, 2, 4, 5 and 8, further comprising a diffusion prevention layer between the carrier foil and the release layer.

10. The ultra-thin copper foil with a carrier foil according to any one of claims 1, 2, 4, 5 and 8, further comprising a heat-resistant layer between the release layer and the ultra-thin copper foil.

11. A copper foil laminate obtained by laminating the ultra-thin copper foil with a carrier foil according to any one of claims 1, 2, 4, 5 and 8 on a resin substrate.

12. A method for manufacturing an ultra-thin copper foil with a carrier foil, comprising forming a laminate structure of a carrier foil, a release layer and an ultra-thin copper foil, The laminated structure is providing a carrier foil; Etching one surface of the carrier foil to form a surface treatment layer; and a release layer and an ultra-thin copper foil are sequentially formed on the surface treatment layer; the surface treatment layer has a surface structure in which protrusions with an average diameter of 10 μm or less are arranged, The method for producing an ultra-thin copper foil with a carrier foil is characterized in that the protrusions have an area density of 8,000 to 10,000 pieces / mm 2 .

13. 13. The method for producing an ultrathin copper foil with a carrier foil according to claim 12, wherein the etching solution for the etching treatment contains one or more selected from the group consisting of sulfuric acid, hydrogen peroxide, nitrogen-containing organic compounds, and sulfur-containing organic compounds.

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