Copper foil composite structure and manufacturing method thereof

Abstract

The invention provides a manufacturing method of a copper foil composite structure. The manufacturing method comprises the following steps: providing a carrier; performing a co-plating process through a copper plating solution and a nitrogen-containing compound to form a copper-nitrogen composite layer on the carrier; and forming a copper foil layer on the copper-nitrogen composite layer. The invention further provides a copper foil composite structure.

Description

TECHNICAL FIELD

[0001] The present application relates to a copper foil composite structure and a manufacturing method thereof. BACKGROUND

[0002] Currently, a release layer is often used in the copper foil structure, however, the stability of the release layer will affect the peeling strength of the subsequent process, for example, the inorganic layer in the existing release layer is prone to vertical flow phenomenon during production, resulting in uneven distribution and peeling strength of the release layer, and the organic layer in the release layer will also increase the peeling strength at high temperature, resulting in difficulty in separating the carrier and the copper foil. SUMMARY

[0003] The present application provides a copper foil composite structure and a manufacturing method thereof, which has excellent performance in peeling strength.

[0004] A manufacturing method of a copper foil composite structure of the present application includes providing a carrier, performing a co-plating process on the carrier by a copper plating solution and a nitrogen-containing compound to form a copper-nitrogen composite layer, and forming a copper foil layer on the copper-nitrogen composite layer.

[0005] In an embodiment of the present application, the copper ion concentration in the above-mentioned copper plating solution ranges between 10 g / L and 60 g / L.

[0006] In an embodiment of the present application, the above-mentioned copper plating solution includes copper pyrophosphate or copper sulfate.

[0007] In an embodiment of the present application, the concentration of the above-mentioned nitrogen-containing compound ranges between 1 ppm and 100 ppm.

[0008] In an embodiment of the present application, the above-mentioned nitrogen-containing compound includes 5-mercapto-1-phenyl-tetrazole, triaminotriazole, benzotriazole, 5-amino tetrazole, 5-methyl benzotriazole, 3,5-diamino-1,2,4-triazole, 5-chlorobenzotriazole, benzotriazole carboxylic acid, or a combination thereof.

[0009] In an embodiment of the present application, the current density of the above-mentioned co-plating process ranges between 1.5 ASD and 4.5 ASD, the co-plating temperature ranges between 40°C and 55°C, and / or the co-plating time ranges between 10 seconds and 30 seconds.

[0010] A copper foil composite structure of the present application includes a carrier, a copper foil layer, and a copper-nitrogen composite layer. The copper-nitrogen composite layer is located between the carrier and the copper foil layer.

[0011] In an embodiment of the present application, the thickness of the above-mentioned copper-nitrogen composite layer ranges between 50 nm and 200 nm, and the thickness of the copper foil layer ranges between 1 μm and 5 μm.

[0012] In an embodiment of the present application, the copper-nitrogen composite layer is directly in contact with the carrier and the copper foil layer, respectively.

[0013] In an embodiment of the present application, the copper foil composite structure further comprises a roughening layer, an oxidation-resistant layer, a rust-proof layer and a silicide layer, which are sequentially stacked on the copper foil layer.

[0014] Based on the above, the present application forms a copper-nitrogen composite layer with high stability on the surface of the carrier by a co-deposition process to form part of the copper foil composite structure, so as to effectively prevent the carrier and the copper atoms in the copper foil layer from being bonded to each other in subsequent processes (such as heat treatment, etc.), thereby achieving excellent performance in terms of peel strength.

[0015] In order to make the above features and advantages of the present application more obvious and easy to understand, the following specific examples are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a partial flowchart of a manufacturing method of a copper foil composite structure according to an embodiment of the present application.

[0017] Figure 2 is a partial layering diagram of a copper foil composite structure according to an embodiment of the present application. DETAILED DESCRIPTION

[0018] In the following detailed description, for the purpose of explanation and not limitation, exemplary embodiments disclosing certain details are set forth in order to provide a thorough understanding of the various principles of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from the specific details disclosed herein. Moreover, descriptions of well-known devices, methods, and materials can be omitted so as not to obscure the descriptions of various principles of the present application.

[0019] Reference is made to the drawings of the present embodiments for a more thorough understanding of the application. The application, may, however, be practiced with various modifications

[0020] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0021] The term "between" used in the specification for defining a numerical range is intended to encompass the equal to the end point values and the range between the end point values, for example, a size range between a first value and a second value means that the size range can cover the first value, the second value and any value between the first value and the second value.

[0022] Figure 1is a partial flowchart diagram of a manufacturing method of a copper foil composite structure according to an embodiment of the present application. Figure 2 is a partial layering diagram of a copper foil composite structure according to an embodiment of the present application.

[0023] Referring to Figure 1 and Figure 2 The manufacturing method of the copper foil composite structure 100 of the present embodiment includes at least the following steps. First, as shown in step S1, a carrier 110 is provided. Next, as shown in step S2, a copper-nitrogen composite layer 120 is formed on the carrier 110 by performing a co-plating process with a copper plating solution and a nitrogen-containing compound. Then, as shown in step S3, a copper foil layer 130 is formed on the copper-nitrogen composite layer 120. Accordingly, the present application forms a copper-nitrogen composite layer 120 with high stability on the surface of the carrier 110 by a co-plating process to form part of the copper foil composite structure 100, so as to effectively prevent the copper atoms in the copper foil layer 130 from being bonded to the carrier 110 in subsequent processes (such as heat treatment, etc.), thereby achieving excellent performance in terms of peel strength.

[0024] In some embodiments, the copper-nitrogen composite layer 120 can provide a release interface, so that the structure after pressing the copper foil layer 130 can be easily separated from the carrier 110, and at the same time, the copper-nitrogen composite layer 120 can have a primer protection function, so that the copper foil composite structure 100 of the present application can omit the use of traditional release layers (inorganic layers and organic layers) and primer layers, thereby avoiding the problems of uneven distribution and peel strength caused by the occurrence of vertical flow, and at the same time, the easy processability of the co-plating process can simplify the process and reduce the manufacturing cost (the current release layer is composed of more expensive metal components).

[0025] In addition, the performance of the product can be further improved by adjusting the parameter conditions of the co-plating process, for example, by the following design.

[0026] In some embodiments, the concentration of copper ions in the copper plating solution ranges from 10 grams per liter (g / L) to 60 grams per liter (g / L) (for example, 10 grams per liter, 20 grams per liter, 30 grams per liter, 40 grams per liter, 50 grams per liter, 60 grams per liter, or any suitable value between 10 grams per liter and 60 grams per liter), but the present application is not limited thereto. Here, the calculation method of the concentration of copper ions is to convert the grams of copper ions in the compound according to the copper content ratio, for example, the copper content ratio of copper sulfate pentahydrate in the copper plating solution is 25.43%, that is, 100 grams of copper sulfate pentahydrate contains 25.43 grams of copper ions.

[0027] In some embodiments, the copper plating solution includes copper pyrophosphate or copper sulfate, but the present application is not limited thereto.

[0028] In some embodiments, the concentration of the nitrogen-containing compound ranges from 1 ppm to 100 ppm (e.g., 1 ppm, 10 ppm, 30 ppm, 50 ppm, 70 ppm, 100 ppm, or any suitable value between 1 ppm and 100 ppm), but the present application is not limited thereto. Here, the concentration of the nitrogen-containing compound is calculated as 1 ppm by adding 1 milligram (mg) of the nitrogen-containing compound to 1 liter (1 L) of the copper plating solution.

[0029] In some embodiments, the nitrogen-containing compound includes 5-mercapto-1-phenyl-tetrazole (5-mercapto-1-phenyl-1H-tetrazole, 5-PTZ), triaminotriazole (3-AT), benzotriazole (BTA), 5-amino tetrazole (5-ATZ), 5-methylbenzotriazole (TTA), 3,5-diamino-1,2,4-triazole, 5-chlorobenzotriazole (5-CLBTA), benzotriazole carboxylic acid (CBTA), or a combination thereof, but the present application is not limited thereto.

[0030] In some embodiments, the current density of the co-plating process ranges from 1.5 ASD to 4.5 ASD (e.g., 1.5 ASD, 2.5 ASD, 3.5 ASD, 4.5 ASD, or any suitable value between 1.5 ASD and 4.5 ASD), but the present application is not limited thereto.

[0031] In some embodiments, the co-plating temperature ranges from 40°C to 55°C (e.g., 40°C, 42°C, 44°C, 46°C, 48°C, 50°C, or any suitable value between 40°C and 50°C), but the present application is not limited thereto.

[0032] In some embodiments, the co-plating time ranges from 10 seconds to 30 seconds (e.g., 10 seconds, 20 seconds, 25 seconds, 30 seconds, or any suitable value between 10 seconds and 30 seconds), but the present application is not limited thereto.

[0033] In some embodiments, a high-temperature lamination process is used in the manufacturing process of the copper foil composite structure 100, and the copper-nitrogen composite layer 120 of the present application can still maintain good stability in this process, that is, temperature (room temperature (e.g., 25°C) or high temperature (e.g., temperature greater than 350°C)) does not have a significant adverse effect on the copper-nitrogen composite layer 120 of the present application, but the present application is not limited thereto.

[0034] In some embodiments, the product often has fine line and high frequency transmission signal requirements, so the copper foil layer 130 must have a lower roughness (for example, Rz less than 0.8 microns) and / or thinning (for example, between 1 microns to 5 microns) design, which due to the limitations of mechanical properties often leads to easy creasing and tearing during transportation. The use of the stacked design of the carrier 110, the copper-nitrogen composite layer 120, and the thinned copper foil layer 130 of the present application can reduce the probability of the occurrence of the foregoing problems, but the present application is not limited thereto.

[0035] In some embodiments, the co-plating process and the pressing process can make the opposite two surfaces of the copper-nitrogen composite layer 120 directly contact the carrier 110 and the copper foil layer 130, respectively, to further reduce the probability of the occurrence of the foregoing problems, but the present application is not limited thereto.

[0036] In some embodiments, the carrier 110 is a copper foil or aluminum foil with a thickness of 18 microns or more as the carrier 110 to further reduce creasing and tearing during transportation in production and can provide sufficient mechanical strength in subsequent pressing processes (such as bonding the thinned copper foil layer 130 with the prepreg), wherein the carrier 110 can be removed by a suitable means after the pressing process, without limitation of the present application.

[0037] In some embodiments, the thickness of the copper-nitrogen composite layer 120 is between 50 nanometers and 200 nanometers (for example, 50 nanometers, 100 nanometers, 150 nanometers, 200 nanometers, or any suitable value between 50 nanometers and 200 nanometers) to provide better protection while reducing the probability of adversely affecting the thickness of the electroplated copper foil layer 130, but the present application is not limited thereto.

[0038] In some embodiments, an acid washing process is performed before step S1, wherein the acid washing process is, for example, cleaning the carrier 110 with sulfuric acid (such as 10% concentration) to remove surface oxides, but the present application is not limited thereto.

[0039] In some embodiments, after step S3, the copper foil composite structure can further include a roughening layer, an oxidation-resistant layer, a rust-prevention layer, and / or a silicide layer (not shown) stacked in sequence on the copper foil layer.

[0040] In some embodiments, the roughening layer is electroplated with a copper plating solution with a copper concentration of between 5 g / L and 15 g / L, a sulfuric acid concentration of between 60 g / L and 90 g / L, and a pulse current as the energy supply, and a thickness range of between 0.5 microns and 1.5 microns, but the present application is not limited thereto.

[0041] In some embodiments, the anti-oxidation layer is formed by a plating solution containing nickel ions and zinc ions, wherein the zinc ion concentration is between 0 g / L and 8 g / L, the nickel ion concentration is between 0.5 g / L and 2 g / L, and the thickness is between 5 nm and 10 nm, but the present application is not limited thereto.

[0042] In some embodiments, the anti-rust layer is a dip chromium acid layer, wherein the potassium dichromate concentration is between 0.8 g / L and 1.5 g / L, and the thickness is between 5 nm and 10 nm, but the present application is not limited thereto.

[0043] In some embodiments, the silicide layer is a sprayed or dip silane, wherein the selected silane is an amino silane (3-aminopropyltrimethoxysilane) with a concentration between 1 g / L and 1.5 g / L, and the thickness is between 5 nm and 10 nm, but the present application is not limited thereto.

[0044] It should be noted that the above numerical ranges, specific types, and related details are not used to limit the present application, and the related conditions can be adjusted according to the actual design requirements. As long as the copper-nitrogen composite layer 120 is formed on the carrier 110 by the copper plating solution and the nitrogen-containing compound co-plating process, it belongs to the protection scope of the present application. In addition, the actual operation means of the co-plating process and the pickling process can be any suitable content known to those skilled in the art, and will not be described here.

[0045] The following examples and comparative examples are listed to illustrate the effect of the present application, but the scope of the right of the present application is not limited to the scope of the examples.

[0046] The copper foil composite structure prepared in each example and comparative example is evaluated according to the following method.

[0047] Peeling strength: at room temperature, the roughening layer is attached to the glass plate with the roughening layer facing down, the test width is 1.27 cm, and the peeling strength between the carrier and the copper foil layer is tested by a tensile testing machine; peeling strength at 200°C: the copper foil layer and the prepreg are hot-pressed at 200°C, the test width is 2.50 cm, and the peeling strength between the carrier and the copper foil layer is tested by a tensile testing machine; peeling strength at 390°C: after the ultra-thin copper foil is baked at 390°C for 5 minutes, the roughening layer is attached to the glass plate with the roughening layer facing down, the test width is 1.27 cm, and the peeling strength between the carrier and the copper foil layer is tested by a tensile testing machine.

[0048] Examples 1-3 and Comparative Example 1 are manufactured in the following manner.

[0049] <Example 1>

[0050] The copper foil composite structure in Example 1 is sequentially stacked with a carrier (thickness of 18 micrometers, material of copper foil), a copper-nitrogen composite layer (thickness of 108 nanometers), a copper foil layer (thickness of 3 micrometers), a roughening layer (copper tumor particles), an oxidation-resistant layer (thickness of 6 nanometers, material of nickel-zinc alloy), a rust-proof layer (thickness of 5 nanometers, material of chromium-containing protective layer), and a silicide layer (thickness of 5 nanometers, material of amino-containing siloxane). The conditions for the co-plating process for forming the copper-nitrogen composite layer are: copper ion concentration in the copper plating solution of 20 g / L, the copper plating solution is a copper sulfate plating solution, nitrogen compound concentration of 25 ppm, the nitrogen compound is 5-ATZ, current density of 2 ASD, co-plating temperature of 45°C, and co-plating time of 15 seconds.

[0051] <Example 2>

[0052] The copper foil composite structure in Example 2 is sequentially stacked with a carrier (thickness of 18 micrometers (um), material of copper foil), a copper-nitrogen composite layer (thickness of 144 nanometers (nm)), a copper foil layer (thickness of 3 um), a roughening layer (copper tumor particles), an oxidation-resistant layer (thickness of 5 nm, material of zinc metal layer), a rust-proof layer (thickness of 5 nm, material of chromium layer), and a silicide layer (thickness of 5 nm, material of amino-containing siloxane). The conditions for the co-plating process for forming the copper-nitrogen composite layer are: copper ion concentration in the copper plating solution of 10 g / L, the copper plating solution is a copper pyrophosphate plating solution, nitrogen compound concentration of 15 ppm, the nitrogen compound is 3-AT, current density of 2 ASD, co-plating temperature of 45°C, and co-plating time of 20 seconds.

[0053] <Example 3>

[0054] The copper foil composite structure in Example 3 is sequentially stacked with a carrier (thickness of 18 um, material of copper foil), a copper-nitrogen composite layer (thickness of 180 nm), a copper foil layer (thickness of 3 um), a roughening layer (copper tumor particles), an oxidation-resistant layer (thickness of 5 nm, material of nickel-zinc metal layer), a rust-proof layer (thickness of 5 nm, material of chromium layer), and a silicide layer (thickness of 5 nm, material of amino-containing siloxane). The conditions for the co-plating process for forming the copper-nitrogen composite layer are: copper ion concentration in the copper plating solution of 40 g / L, the copper plating solution is a copper pyrophosphate plating solution, nitrogen compound concentration of 10 ppm, the nitrogen compound is CBTA, current density of 2.5 ASD, co-plating temperature of 45°C, and co-plating time of 25 seconds.

[0055] <Comparative Example 1>

[0056] Comparative Example 1 is similar to Example 1, except that the copper-nitrogen composite layer is replaced by a conventional release layer and primer layer (commercially available model NPUE).

[0057] From the results of Table 1, it can be concluded that the peel strength of Examples 1-3 having the copper-nitrogen composite layer of the present application is less than that of Comparative Example 1, for example, Example 1 can be reduced by about 2 times at room temperature, and even by about 3 times at high temperature, thus the copper foil composite structure of the present application indeed has a superior performance in peel strength.

[0058] Table 1

[0059]

[0060] In summary, the present application forms a copper-nitrogen composite layer with high stability on the surface of the carrier by co-plating process to form part of the copper foil composite structure, in this way, it can effectively prevent the carrier and copper atoms in the copper foil layer from being bonded to each other in subsequent processes (such as heat treatment, etc.), thereby having a superior performance in peel strength. Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of manufacturing a copper foil composite structure, characterized by, The method comprises: providing a carrier; performing a co-plating process with a copper plating solution and a nitrogen-containing compound to form a copper-nitrogen composite layer on the carrier; and forming a copper foil layer on the copper-nitrogen composite layer. The copper ion concentration in the copper plating solution ranges from 10 g / L to 60 g / L.

2. The method of manufacturing a copper foil composite structure according to claim 1, characterized by, The copper plating solution comprises copper pyrophosphate or copper sulfate.

3. The method of manufacturing a copper foil composite structure according to claim 1, characterized by, The concentration of the nitrogen-containing compound ranges from 1 ppm to 100 ppm.

4. The method of manufacturing a copper foil composite structure according to claim 1, characterized by, The nitrogen-containing compound comprises 5-mercapto-1-phenyl-tetrazole, triaminotriazole, benzotriazole, 5-amino tetrazole, 5-methyl benzotriazole, 3,5-diamino-1,2,4-triazole, 5-chlorobenzotriazole, benzotriazole carboxylic acid, or a combination thereof.

5. The method of manufacturing a copper foil composite structure according to claim 1, characterized by, The current density of the co-plating process ranges from 1.5 ASD to 4.5 ASD, the co-plating temperature ranges from 40°C to 55°C, and / or the co-plating time ranges from 10 seconds to 30 seconds.

6. The method of manufacturing a copper foil composite structure according to claim 1, characterized by, The method comprises:

7. A copper foil composite structure, characterized by, a carrier; a copper foil layer; and a copper-nitrogen composite layer between the carrier and the copper foil layer. The thickness of the copper-nitrogen composite layer ranges from 50 nm to 200 nm, and the thickness of the copper foil layer ranges from 1 μm to 5 μm. The two surfaces of the copper-nitrogen composite layer are in direct contact with the carrier and the copper foil layer, respectively.

8. The copper foil composite structure according to claim 7, wherein The method further comprises a roughening layer, an oxidation-resistant layer, a rust-resistant layer, and a silicide layer, which are sequentially stacked on the copper foil layer.

9. The copper foil composite structure of claim 7, wherein ​ 10. The copper foil composite structure of claim 7, wherein ​

Images