Preparation method of bi-component stripping layer carrier copper foil and bi-component stripping layer carrier copper foil

Abstract

The invention relates to the technical field of electrolytic copper foil processing, printed circuit board processing and electrolytic copper foil, in particular to a preparation method of a bi-component stripping layer carrier copper foil and the bi-component stripping layer carrier copper foil. The preparation method provided by the invention comprises the following steps: preparing a carrier copper layer; preparing a first inorganic stripping layer on the smooth surface of the carrier copper layer through an electrochemical / physical vapor deposition method; preparing a second inorganic stripping layer on the surface of the first inorganic stripping layer through a low-temperature chemical vapor deposition method; preparing an ultra-thin copper layer on the surface of the second inorganic stripping layer through a pulse electrochemical deposition method; carrying out roughening treatment on the ultra-thin copper layer; and constructing a non-copper functional layer on the surface of the roughened ultra-thin copper layer, and carrying out silane coupling agent coating treatment to obtain the double-component stripping layer carrier copper foil. The two-component inorganic matter is used as the stripping layer of the carrier copper foil, the heat resistance of the stripping layer of the carrier copper foil is improved, and meanwhile the stability of the separating force between the ultra-thin copper layer and the carrier copper layer is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic copper foil processing, printed circuit board processing and electrolytic copper foil, and particularly relates to a preparation method of a double-component release layer carrier copper foil and the double-component release layer carrier copper foil. BACKGROUND

[0002] Light and thin and miniaturization are the clear development trend of consumer electronics represented by advanced smart phones. Under the application demand of device size reduction and functionalization demand improvement, increasing the wiring density to arrange as many lines as possible in the smallest area is the universally recognized solution. Ultra-high density wiring needs to compress the line width and line spacing as much as possible under the premise of meeting performance requirements and reliability. The extremely thin peelable attached carrier copper foil is the key material to realize ultra-fine line width and line spacing L / S≤25 / 25μm.

[0003] The release layer is the key to ensure that the extremely thin peelable attached carrier copper foil can be stably separated between the extremely thin functional copper layer and the carrier layer. The composition and uniformity of the release layer directly affect the separability and separation force stability of the extremely thin peelable attached carrier copper foil. The traditional carrier copper foil mostly uses organic matter as the release layer, which can realize stable and controllable separation between the extremely thin copper layer and the carrier layer within a certain temperature range. It should be pointed out that: generally, the heat resistance temperature of organic matter is lower than that of inorganic matter, and it is easy to decompose at relatively high temperature. According to the actual use experience, when the pressing temperature is higher than 230℃, the carrier copper foil with organic component as the release layer cannot stably maintain the separation force. After multiple pressing, the extremely thin copper layer and the carrier layer may be adhered, resulting in ineffective separation. Therefore, improving the heat resistance of the release layer of the carrier copper foil is of great significance to expand the application field of the carrier copper foil and ensure the multiple pressing processability of the carrier copper foil. SUMMARY

[0004] In view of the above-mentioned shortcomings of the prior art, the present application aims to develop a carrier copper foil release layer with inorganic matter as the main component to significantly improve its heat resistance and expand the application range of the carrier copper foil in high-temperature process environment. Through innovative double-component structure design, on the one hand, the thermal stability of the release layer is improved, and on the other hand, the interfacial separation force between the extremely thin copper layer and the carrier copper layer is precisely controlled to ensure the high stability and consistency of the peeling process.

[0005] The first aspect of the present application provides a preparation method of a double-component release layer carrier copper foil, comprising the following steps:

[0006] (1) preparing a carrier copper layer;

[0007] (2) preparing a first inorganic release layer on the smooth surface of the carrier copper layer by an electrochemical / physical vapor deposition method;

[0008] (3) preparing a second inorganic peeling layer on the surface of the first inorganic peeling layer by a low-temperature chemical vapor deposition method;

[0009] (4) preparing an extremely thin copper layer on the surface of the second inorganic stripping layer by a pulse electrochemical deposition method;

[0010] (5) Roughening of the ultra-thin copper layer;

[0011] (6) A non-copper functional layer is constructed on the surface of the roughened ultra-thin copper layer, and a silane coupling agent coating treatment is performed to obtain a two-component peeling layer carrier copper foil.

[0012] In some embodiments of the present invention, in step (1), the thickness of the carrier copper layer is 12-35 μm, and the surface roughness Rz of the carrier copper layer is between 0.9-1.5 μm.

[0013] In some embodiments of the present invention, in step (1), the method for preparing the carrier copper layer includes: using a titanium roller as a cathode, DSA as an anode, and acidic copper sulfate containing additives as an electrolyte in an anode tank, and depositing a copper foil with uniform thickness and physical properties on the surface of the titanium cathode roller by direct current electrochemical deposition to obtain the carrier copper layer.

[0014] In some embodiments of the present invention, in step (2), the first inorganic stripping layer is selected from nickel, nickel-based alloy, cobalt, cobalt-based alloy or molybdenum, and has a thickness of 8-12 nm.

[0015] In some embodiments of the present invention, in step (3), the second inorganic peeling layer is multilayer graphene with a thickness of 1-2 nm.

[0016] In some embodiments of the present invention, in step (4), the copper ion concentration in the electrolyte used for the pulse electrochemical deposition is 90-100 g / L, the sulfuric acid concentration is 125-150 g / L, the chloride ion concentration is 10-15 mg / L, and the additive concentration is 5-10 mg / L.

[0017] In some embodiments of the present invention, in step (4), the temperature of the electrolyte is 45-50°C, the flow rate of the electrolyte is 40-45m 3 / h, the average current density is 2000-2500A / m 2 , the duty cycle is 25%-33%.

[0018] In some embodiments of the present invention, in step (5), a pulse current is applied simultaneously during the roughening process.

[0019] In some embodiments of the present application, in step (5), the concentration of copper ions in the electrolyte for the roughening treatment is 10-15 g / L, the concentration of sulfuric acid is 90-120 g / L, and the concentration of the additive is 10-20 mg / L; the temperature of the electrolyte is 25-30℃, and the flow rate of the electrolyte is 8-12 m 3 / h.

[0020] In some embodiments of the present application, in step (6), the construction of the non-copper functional layer comprises sequentially preparing a nickel-based barrier layer and a zinc-chromium composite anti-oxidation layer on the surface of the ultra-thin copper layer after the roughening treatment by a pulse electrochemical deposition method.

[0021] In some embodiments of the present application, in step (6), the silane coupling agent is selected from KBM-503 or KBM-903, the concentration of the silane coupling agent is 0.5wt%-1.5wt%, the flow rate of the silane coupling agent is 1.0-2.5 m 3 / h, and the coated copper foil is placed in an oven for baking.

[0022] In some embodiments of the present application, in step (6), the rough surface of the carrier copper layer is simultaneously constructed with the non-copper functional layer on the surface of the ultra-thin copper layer, and the silane coupling agent coating treatment is performed.

[0023] The second aspect of the present application provides a dual-component separation layer carrier copper foil prepared by the preparation method.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1. The present application uses dual-component inorganic materials as the separation layer of the carrier copper foil, which improves the heat resistance of the separation layer of the carrier copper foil and enhances the stability of the separation force between the ultra-thin copper layer and the carrier copper layer.

[0026] 2. The present application realizes the controllable deposition of the ultra-fine grain ultra-thin copper layer by the additive-assisted pulse electrochemical deposition, which is beneficial to improving the rapid etching performance of the ultra-thin copper layer and the line width and distance of the carrier board circuit; the ultra-fine roughening surface treatment process reduces the roughness of the treated surface of the ultra-thin copper layer while ensuring the separation strength between the ultra-thin copper layer and the carrier board material, and is also beneficial to improving the etching performance of the ultra-thin copper layer, realizing the ultra-fine circuit with L / S not more than 25 / 25 μm.

[0027] 3. The non-copper functional layer constructed by the pulse electrochemical deposition has small film thickness and high film density, which can ensure the chemical resistance and heat resistance of the copper foil at a low content.

[0028] 4. The present application constructs a chemical bonding layer on the basis of the pulse electrochemical deposition of the non-copper functional layer, which can increase the density of active sites per unit area, improve the quality of the chemical bonding layer, and improve the separation strength between the ultra-thin copper layer and the carrier board material. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The figure is a schematic diagram of the process flow for preparing a two-component peeling layer carrier copper foil according to an embodiment of the present invention.

[0030] Figure 2 Schematic diagram of the structure of a two-component peel-away layer carrier copper foil according to one embodiment of the present invention.

[0031] Figure 3 These are SEM images of the rough surface of the ultra-thin copper layer in the samples prepared in Example 1 and Comparative Examples 1 to 3 of the present invention, where (a) is Example 1; (b) is Comparative Example 1; (c) is Comparative Example 2; and (d) is Comparative Example 3.

[0032] Figure 4 The figure shows a comparison of the separation force stability of samples obtained from Example 1 of the present invention and Comparative Examples 1 to 3, wherein (a) is Example 1; (b) is Comparative Example 1; (c) is Comparative Example 2; and (d) is Comparative Example 3.

[0033] Reference numerals:

[0034] S01-carrier copper layer; S02-first inorganic peeling layer; S03-second inorganic peeling layer; S04-ultra-thin copper layer; S05-ultra-thin copper layer roughening layer; S06-non-copper functional layer and silane coupling agent layer. DETAILED DESCRIPTION

[0035] The following further illustrates a method for preparing a two-component peeling layer carrier copper foil and a two-component peeling layer carrier copper foil of the present invention in conjunction with the accompanying drawings and specific embodiments.

[0036] The first aspect of the present invention provides a method for preparing a two-component peeling layer carrier copper foil, such as Figure 1 As shown, the following steps are included:

[0037] (1) preparing a carrier copper layer;

[0038] (2) preparing a first inorganic release layer on the polished surface of the carrier copper layer by electrochemical / physical vapor deposition;

[0039] (3) preparing a second inorganic peeling layer on the surface of the first inorganic peeling layer by a low-temperature chemical vapor deposition method;

[0040] (4) preparing an extremely thin copper layer on the surface of the second inorganic stripping layer by a pulse electrochemical deposition method;

[0041] (5) Roughening of the ultra-thin copper layer;

[0042] (6) A non-copper functional layer is constructed on the surface of the roughened ultra-thin copper layer, and a silane coupling agent coating treatment is performed to obtain a two-component peeling layer carrier copper foil.

[0043] In some embodiments of the present invention, in step (1), the thickness of the carrier copper layer is 12-35 μm, and the surface roughness Rz of the carrier copper layer is between 0.9-1.5 μm. In some specific embodiments of the present invention, the thickness of the carrier copper layer is 18 μm.

[0044] In some embodiments of the present invention, in step (1), the method for preparing the carrier copper layer comprises: depositing a copper foil having uniform thickness and physical properties on the surface of the titanium cathode roller by direct current electrochemical deposition in an anode tank, using a titanium roller as a cathode, DSA as an anode, and acidic copper sulfate containing an additive as an electrolyte, to obtain the carrier copper layer. In some specific embodiments of the present invention, the additive is hydroxyethyl cellulose. The smooth surface roughness of the carrier layer copper foil is regulated by offline polishing and online polishing, and the crystal structure and roughness of the matte surface of the carrier layer copper foil are regulated by the additive and current density.

[0045] In some embodiments of the present invention, in step (1), the concentration of copper ions in the electrolyte is 80-90 g / L, the concentration of sulfuric acid is 120-150 g / L, the concentration of chloride ions is 15-25 mg / L, and the concentration of hydroxyethyl cellulose is 20-30 mg / L.

[0046] In some embodiments of the present invention, in step (1), the temperature of the electrolyte is 45-50°C, can be 45-46°C, 46-47°C, 47-48°C, 48-49°C, or 49-50°C, and the flow rate of the electrolyte is 40-45m 3 / h, can be 40-41m 3 / h, 41-42m 3 / h, 42-43m 3 / h, 43-44m 3 / h, or 44-45m 3 / h, current density is 7500-8500A / m 2 , which can be 7500-7700A / m 2 , 7700-7900A / m 2 , 7900-8000A / m 2 , 8000-8200A / m 2 , 8200-8400A / m 2 , or 8400-8500A / m 2 .

[0047] In some embodiments of the present invention, in step (2), the first inorganic stripping layer is selected from nickel, nickel-based alloy, cobalt, cobalt-based alloy or molybdenum, and has a thickness of 8-12 nm. In some preferred embodiments of the present invention, the first inorganic stripping layer is nickel, and electrochemical deposition and PVD deposition can achieve precise control of the thickness of the metal nickel layer and the quality of the film layer by controlling the process parameters. When the first inorganic stripping layer is prepared by electrochemical deposition, the concentration of nickel ions in the electrolyte used for electrochemical deposition is 5-10 g / L, the concentration of potassium pyrophosphate is 150-200 g / L, the pH of the electrolyte is 10.0-10.5, the temperature of the electrolyte is 38-42°C, can be 38-40°C, or can be 40-42°C, and the flow rate of the electrolyte is 5-10 m 3 / h, can be 5-7m 3 / h, 7-9m 3 / h, or 9-10m 3 / h, current density is 200-300A / m 2 , can be 200-250A / m 2 , 250-300A / m 2 , or 300-350A / m 2 ; When the first inorganic stripping layer is prepared by a physical vapor deposition method, the physical vapor deposition is a DC sputtering deposition, the target material is a nickel target, the vacuum degree is 100-110mTorr, which can be 100-105mTorr, or 105-110mTorr, the argon flow rate is 80-150sccm, which can be 80-90sccm, 90-100sccm, 100-110sccm, 110-120sccm, 120-130sccm, 130-140sccm, or 140-150sccm, the sputtering power is 10-20kW, which can be 10-15kW, or 15-20kW, and the sputtering time is 5-15min, which can be 5-10min, or 10-15min.

[0048] In some embodiments of the present application, in step (3), the second inorganic exfoliation layer is multilayer graphene with a thickness of 1-2 nm. Multilayer graphene is grown by chemical vapor deposition (CVD) using methane CH4 and hydrogen H2 as raw materials, with the aid of the relatively high solubility of carbon atoms in nickel. As the second inorganic exfoliation layer, graphene has high electrical conductivity and exfoliation performance, which is conducive to the electrochemical deposition of the extremely thin copper layer and can effectively improve the stability of the separation force between the carrier layer and the extremely thin copper layer. The pressure of the low-temperature chemical vapor deposition is 40-60 Torr, which can be 40-45 Torr, 45-50 Torr, 50-55 Torr, or 55-60 Torr. The flow ratio of methane, argon and hydrogen is 1:3:1. The cooling rate is 10-15 ℃ / s, which can be 10-12 ℃ / s, 12-14 ℃ / s, or 14-15 ℃ / s. The growth temperature is 800-950 ℃, which can be 800-850 ℃, 850-900 ℃, or 900-950 ℃. The growth time is 50-70 min, which can be 50-55 min, 55-60 min, 60-65 min, or 65-70 min.

[0049] In some embodiments of the present application, in step (4), the concentration of copper ions in the electrolyte used for pulse electrochemical deposition is 90-100 g / L, the concentration of sulfuric acid is 125-150 g / L, the concentration of chloride ions is 10-15 mg / L, and the concentration of additives is 5-10 mg / L. In some specific embodiments of the present application, the additive is 2-mercapto-5-benzimidazole sodium sulfonate. The additive-assisted pulse electrochemical deposition realizes the controllable deposition of the ultra-fine grain extremely thin copper layer. Pulse electrochemical deposition can effectively increase the peak current density and overpotential in the electrochemical deposition process, which is conducive to the nucleation and growth of ultra-fine grains. The additive forms a complex with copper ions to control the overpotential in the electrochemical reduction process of copper ions, thereby realizing the regulation of the crystal structure of the copper foil. In addition, the additive can be doped between the grain boundaries of the copper foil crystal structure to inhibit the recrystallization process of adjacent grains during the heat treatment process and use. Therefore, the additive-assisted pulse electrochemical deposition can realize the ultra-fine grain copper foil with excellent crystal structure stability.

[0050] In some embodiments of the present application, in step (4), the temperature of the electrolyte is 45-50 ℃, which can be 45-47 ℃, 47-49 ℃, or 49-50 ℃. The electrode liquid flow rate is 40-45 m 3 / h, which can be 40-42 m 3 / h, 42-44 m 3 / h, or 44-45 m 3 / h, the average current density is 2000-2500 A / m 2 , the average current density can be 2000-2200 A / m 2 , 2200-2400 A / m 2 , the average current density can also be 2400-2500 A / m 2 , the duty cycle is 25%-33%, which can be 20%-25%, 25%-30%, or 30%-33%.

[0051] In some embodiments of the present application, in step (5), a pulse current is applied during the roughening process. The average current density of the pulse current is 500-800 A / m 2 , the average current density can be 500-600 A / m 2 , 600-700 A / m 2 , 700-750 A / m 2 , the average current density can also be 750-800 A / m 2 , the duty cycle is 15%-30%, which can be 15%-20%, 20%-25%, or 25%-30%, the processing time is 8-12 s, which can be 8-10 s, or 10-12 s, and the processing times is 2-3 times.

[0052] In some embodiments of the present application, in step (5), the concentration of copper ions in the electrolyte for roughening is 10-15 g / L, the concentration of sulfuric acid is 90-120 g / L, and the concentration of the additive is 10-20 mg / L; the temperature of the electrolyte is 25-30℃, which can be 25-27℃, 27-29℃, or 29-30℃, and the flow rate of the electrolyte is 8-12 m 3 / h, which can be 8-10 m 3 / h, or 10-12 m 3 / h. In some specific embodiments of the present application, the additive is sodium tungstate. The pulse electrochemical deposition process assisted by the additive is used for ultra-fine roughening of the extremely thin copper layer, thereby enhancing the binding stability between the extremely thin copper layer and the carrier material. The ultra-fine roughening process can realize copper tumors with an average size of sub-microns, thereby increasing the effective binding area between the copper foil and the carrier material while reducing the surface profile of the copper foil, so as to realize stable binding between the extremely thin copper layer and the carrier material.

[0053] In some embodiments of the present invention, in step (6), the construction of the non-copper functional layer includes sequentially preparing a nickel-based barrier layer (thickness of 0.1-10 nm) and a zinc-chromium composite anti-oxidation layer (0.2-20 nm) on the surface of the roughened ultra-thin copper layer by a pulse electrochemical deposition method. In some embodiments of the present invention, the concentration of nickel ions in the electrolyte used for the pulse electrochemical deposition to prepare the nickel-based barrier layer is 10-20 g / L, the concentration of boric acid is 30-50 g / L, and the concentration of sodium hypophosphite is 50-60 g / L. The temperature of the electrolyte is 35-40°C, which can be 35-37°C, 37-39°C, or 39-40°C. The electrolyte flow rate is 5-10 m 3 / h, can be 5-7m 3 / h, 7-9m 3 / h, or 9-10m 3 / h, average current density is 25-50A / m 2 , can be 25-30A / m 2 , 30-35A / m 2 , 35-40A / m 2 , 40-45A / m 2 , or 45-50A / m 2 , the duty cycle is 20%-33%, which can be 20%-25%, 25%-30%, or 30%-33%, and the processing time is 8-12s, which can be 8-10s, or 10-12s. The concentration of zinc ions in the electrolyte used for pulse electrochemical deposition to prepare zinc-based high-temperature antioxidant layer is 5-10g / L, the concentration of boric acid is 30-50g / L, the concentration of sodium hypophosphite is 50-60g / L, the temperature of the electrolyte is 35-40℃, which can be 35-37℃, 37-39℃, or 39-40℃, and the electrolyte flow rate is 5-10m 3 / h, can be 5-7m 3 / h, 7-9m 3 / h, or 9-10m 3 / h, average current density is 25-50A / m 2 , can be 25-30A / m 2 , 30-35A / m 2 , 35-40A / m 2 , 40-45A / m 2 , or 45-50A / m 2, the duty cycle is 20%-33%, which can be 20%-25%, 25%-30%, or 30%-33%, the processing time is 8-12s, which can be 8-10s, or 10-12s; the concentration of hexavalent chromium ions (chromic anhydride) in the electrolyte used for pulse electrochemical deposition to prepare the chromium-based room-temperature antioxidant layer is 2-5g / L, the electrolyte temperature is 35-40℃, which can be 35-37℃, 37-39℃, or 39-40℃, and the electrolyte flow rate is 5-10m 3 / h, can be 5-7m 3 / h, 7-9m 3 / h, or 9-10m 3 / h, average current density is 25-50A / m 2 , can be 25-30A / m 2 , 30-35A / m 2 , 35-40A / m 2 , 40-45A / m 2 , or 45-50A / m 2 The duty cycle is 20%-33%, which can be 20%-25%, 25%-30%, or 30%-33%, and the processing time is 8-12 seconds, which can be 8-10 seconds, or 10-12 seconds. The nanometer-thick non-copper functional layer is mainly used to improve the chemical resistance and high temperature resistance of the copper foil.

[0054] The chemical bonding layer of the silane coupling agent improves the peel strength of the interfacial bonding by forming a chemical bond between the copper foil and the carrier material. In some embodiments of the present invention, in step (6), the silane coupling agent is selected from KBM-503 or KBM-903, the concentration of the silane coupling agent is 0.5wt%-1.5wt%, can be 0.5wt%-1.0wt%, or can be 1.0wt%-1.5wt%, and the flow rate of the silane coupling agent is 1.0-2.5m 3 / h, can be 1.0-1.5m 3 / h, 1.5-2.0m 3 / h, or 2.0-2.5m 3 / h, and then placed in an oven for baking after coating. Preferably, the baking temperature is 110-180°C, which can be 110-120°C, 120-130°C, 130-140°C, 140-150°C, 150-160°C, 160-170°C, or 170-180°C.

[0055] In some embodiments of the present invention, Figure 1 and Figure 2As shown, in step (6), the rough surface of the carrier copper layer is synchronously constructed with the surface of the ultra-thin copper layer with a non-copper functional layer, and a silane coupling agent coating treatment is performed.

[0056] The second aspect of the present application provides a two-component separation layer carrier copper foil prepared by the above preparation method. As shown in the drawings, Figure 2 As shown, the two-component separation layer carrier copper foil includes a carrier copper layer S01, and a first inorganic separation layer S02, a second inorganic separation layer S03, an ultra-thin copper layer S04, an ultra-thin copper layer roughening layer S05, a non-copper functional layer and a silane coupling agent layer S06 are sequentially arranged on the smooth surface of the carrier copper layer. In some embodiments of the present application, as shown in the drawings, Figure 2 As shown, the rough surface of the carrier copper layer is also provided with a non-copper functional layer and a silane coupling agent layer S06, which ensures that no oxidation occurs during processing. The two-component separation layer carrier copper foil provided by the present application has good separation performance and etching performance.

[0057] Before further describing the specific embodiments of the present application, it should be understood that the scope of protection of the present application is not limited to the following specific embodiments; it should also be understood that the terms used in the embodiments of the present application are for the purpose of describing the specific embodiments, and are not intended to limit the scope of protection of the present application.

[0058] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as generally understood by those skilled in the art. In addition to the specific methods, devices, materials used in the examples, any method, device and material of the prior art similar or equivalent to the methods, devices and materials described in the embodiments of the present application can also be used to implement the present application according to the mastery of the prior art by those skilled in the art and the description of the present application.

[0059] Unless otherwise stated, the experimental methods, detection methods, preparation methods disclosed in the present application all use conventional analytical chemistry and related fields. Unless otherwise stated, the materials and equipment used in the present application are commercially available.

[0060] Example 1

[0061] The preparation method of the two-component separation layer carrier copper foil of the present embodiment includes the following steps:

[0062] (1) Preparation of carrier copper layer: in an anode tank, a titanium roller is used as a cathode, a DSA is used as an anode, and an acid copper sulfate containing an additive is used as an electrolyte. A copper foil with a thickness of 18 μm and uniform physical properties is deposited on the surface of the titanium cathode roller by direct current electrochemical deposition, which is the carrier copper layer. The key process parameters during the production of the carrier copper layer are as follows:

[0063] Copper ion concentration: 90 g / L

[0064] Sulfuric acid concentration: 125g / L

[0065] Chloride ion concentration: 20 mg / L

[0066] Hydroxyethyl cellulose concentration: 30 mg / L

[0067] Electrolyte temperature: 50°C

[0068] Electrolyte flow rate: 45m 3 / h

[0069] Current density: 8000A / m 2 .

[0070] (2) Preparation of the First Inorganic Stripping Layer: A 10 nm thick layer of nickel was deposited on the polished surface of the carrier copper layer by electrochemical deposition. The key process parameters during the electrochemical deposition of nickel were as follows:

[0071] Nickel ion concentration: 10g / L

[0072] Potassium pyrophosphate concentration: 200g / L

[0073] pH: 10.0

[0074] Electrolyte temperature: 40°C

[0075] Electrolyte flow rate: 10m 3 / h

[0076] Current density: 250A / m 2 .

[0077] (3) Preparation of the second inorganic peeling layer: A multilayer graphene layer with a thickness of 1.0 nm was deposited on the surface of the metallic nickel peeling layer by CVD chemical vapor deposition as the second inorganic peeling layer. The key process parameters for chemical vapor deposition of multilayer graphene on the metallic nickel surface are as follows:

[0078] Pressure: 50 Torr

[0079] Methane flow rate: 100 sccm

[0080] Argon flow rate: 300 sccm

[0081] Hydrogen flow rate: 100 sccm

[0082] Cooling rate: 10℃ / s

[0083] Growth temperature: 850℃

[0084] Growth time: 60 minutes.

[0085] (4) Preparation of the ultra-thin copper layer: An ultra-thin copper layer with a thickness of 3 μm is deposited on the surface of the second inorganic release layer by additive-assisted pulse electrochemical deposition. Pulse electrodeposition can increase the nucleation density and effectively reduce the grain size. The introduction of additives regulates the electrochemical reduction overpotential of Cu-complexes and regulates the electrochemical deposition of copper atoms. The key process parameters during the deposition of the ultra-thin copper layer are as follows:

[0086] Copper ion concentration: 100 g / L

[0087] Sulfuric acid concentration: 125 g / L

[0088] Chloride ion concentration: 10 mg / L

[0089] 2-Mercapto-5-benzimidazole sulfonic acid sodium concentration: 10 mg / L

[0090] Electrolyte temperature: 50 °C

[0091] Electrolyte flow rate: 45 m 3 / h

[0092] Average current density: 2000 A / m 2

[0093] Duty cycle: 25%.

[0094] (5) Ultra-thin copper layer roughening treatment: Introduce pulse current and additives with grain refinement effect during the roughening surface treatment process to achieve sub-micron diameter ultra-fine copper tumors. Ultra-fine copper tumors not only can reduce the surface roughness after roughening treatment of the ultra-thin copper layer, but also are beneficial to shorten the etching time in the downstream line processing process and reduce the risk of micro-short circuit caused by incomplete etching. The key process parameters during the ultra-fine roughening treatment of the ultra-thin copper layer are as follows:

[0095] Copper ion concentration: 15 g / L

[0096] Sulfuric acid concentration: 120 g / L

[0097] Sodium tungstate concentration: 15 mg / L

[0098] Electrolyte temperature: 30 °C

[0099] Electrolyte flow rate: 10 m 3 / h

[0100] Average current density: 750 A / m 2

[0101] Duty cycle: 30%

[0102] Treatment time: 10 s

[0103] Treatment times: 3 times.

[0104] (6) Constructing non-copper functional layer: Constructing nickel-based barrier layer, zinc-based high-temperature oxidation-resistant layer and chromium-based room-temperature oxidation-resistant layer on the surface of the ultra-thin copper layer and the rough surface of the carrier copper layer in turn by means of pulse electrochemical deposition. The key process parameters in the construction of the non-copper metal functional layer are as follows:

[0105] Nickel-based barrier layer electrolyte: nickel ion concentration 10 g / L; boric acid concentration 50 g / L; sodium hypophosphite concentration 60 g / L;

[0106] Zinc-based high-temperature oxidation-resistant layer electrolyte: zinc ion concentration 10 g / L, boric acid concentration 50 g / L, sodium hypophosphite concentration 60 g / L;

[0107] Chromium-based room-temperature oxidation-resistant layer electrolyte: hexavalent chromium ion (chromic anhydride) concentration 2.5 g / L, pH 11;

[0108] Electrolyte temperature: 40°C

[0109] Electrolyte flow rate: 10 m 3 / h

[0110] Average current density: 50 A / m 2

[0111] Duty cycle: 33%

[0112] Treatment time: 10 s.

[0113] (7) Coating silane coupling agent: Coating silane coupling agent on the surface of the ultra-thin copper layer and the rough surface of the carrier copper layer with the non-copper functional layer at the same time, forming O-Si-O chemical bonds between the silane coupling agent and the hydroxyl groups hanging on the surface of the copper foil, so as to improve the peeling strength between the ultra-thin copper layer and the carrier material. The key process parameters in the process of coating the silane coupling agent are as follows:

[0114] Silane coupling agent: KBM-503

[0115] Silane coupling agent concentration: 1.0 wt%

[0116] Silane coupling agent flow rate 2 m 3 / h

[0117] Oven temperature: 120°C.

[0118] Example 2

[0119] The difference between this example and Example 1 is that the preparation method of the first inorganic peeling layer is changed from electrochemical deposition to direct current sputtering deposition. The key process parameters for direct current sputtering deposition of a nanoscale-thickness metal nickel peeling layer are as follows:

[0120] Target material: nickel target (purity: 99.999 at%)

[0121] Vacuum degree: 100mTorr

[0122] Argon flow rate: 100 sccm

[0123] Sputtering power: 15kW

[0124] Sputtering time: 10 min.

[0125] Example 3

[0126] The difference between this example and Example 1 lies in the adjustment of the process parameters during the low-temperature chemical vapor deposition process for preparing multi-layer graphene (the second inorganic exfoliation layer). The cooling rate was adjusted from 10°C / s to 15°C / s, and the growth temperature was adjusted from 850°C to 950°C. All other parameters remained unchanged.

[0127] Pressure: 50 Torr

[0128] Methane flow rate: 100 sccm

[0129] Argon flow rate: 300 sccm

[0130] Hydrogen flow rate: 100 sccm

[0131] Cooling rate: 15℃ / s

[0132] Growth temperature: 950℃

[0133] Growth time: 60 minutes.

[0134] Example 4

[0135] The difference between this embodiment and embodiment 1 is that the process parameters of the pulse electrochemical deposition process for preparing the ultra-thin copper layer are adjusted. The average current density is increased from 2000A / m 2 Adjusted to 2500A / m 2 , adjust the duty cycle from 25% to 33%, and keep the other parameters unchanged.

[0136] Copper ion concentration: 100g / L

[0137] Sulfuric acid concentration: 125g / L

[0138] Chloride ion concentration: 10mg / L

[0139] Sodium 2-mercapto-5-benzimidazole sulfonate concentration: 10 mg / L

[0140] Electrolyte temperature: 50°C

[0141] Electrolyte flow rate: 45m 3 / h

[0142] Average current density: 2500A / m 2

[0143] Duty cycle: 33%.

[0144] Example 5

[0145] The difference between this embodiment and embodiment 1 is that the process parameters in the roughening process of the ultra-thin copper layer are adjusted. The average current density is increased from 750A / m 2 Adjusted to 500A / m 2 , adjust the duty cycle from 30% to 15%, adjust the number of processing times from 3 times to 2 times, and keep the other parameters unchanged.

[0146] Average current density: 500A / m 2

[0147] Duty cycle: 15%

[0148] Number of treatments: 2 times.

[0149] Example 6

[0150] The difference between this embodiment and embodiment 1 is that the process parameters in the process of coating the non-copper functional layer with silane coupling agent are adjusted. The silane coupling agent is adjusted from KBM-503 to KBM-903, the concentration of the silane coupling agent is adjusted from 1.0wt% to 0.5wt%, and the flow rate of the silane coupling agent is adjusted from 2m 3 / h is adjusted to 1m 3 / h, adjust the oven temperature from 120℃ to 180℃, and keep the other parameters unchanged.

[0151] Silane coupling agent: KBM-903

[0152] Silane coupling agent concentration: 0.5wt%

[0153] Silane coupling agent flow rate 1m 3 / h

[0154] Oven temperature: 180℃.

[0155] Comparative Example 1

[0156] The same procedures as in Example 1 were followed except that a single-component CBTA carboxylbenzotriazole organic stripping layer (organic stripping layer) was used instead of the metal nickel-graphene two-component stripping layer.

[0157] Comparative Example 2

[0158] The same procedures as in Example 1 are followed except that a CBTA carboxylbenzotriazole organic stripping layer and a metal nickel inorganic stripping layer (organic-inorganic two-component stripping layer) are used instead of the metal nickel-graphene two-component stripping layer.

[0159] Comparative Example 3

[0160] The rest is the same as Example 1 except that the metal nickel inorganic stripping layer is used instead of the metal nickel-graphene two-component stripping layer.

[0161] Figure 3 SEM images of the rough surface of the ultra-thin copper layer of the samples prepared in Example 1 and Comparative Examples 1-3 of the present application are shown in Figure 1. It can be seen from Figure 1 that the same pulse electrochemical deposition method is used to prepare the ultra-thin copper layer in Example 1 and Comparative Examples 1-3, and the size of the copper tumor on the surface of the ultra-thin copper layer prepared on the metal nickel-graphene two-component stripping layer in Example 1 is smaller after surface treatment, while the size of the copper tumor on the surface of the ultra-thin copper layer prepared on the stripping layer in Comparative Examples 1-3 is larger after surface treatment, indicating that the stripping layer has a significant impact on the micro-morphology of the rough surface of the ultra-thin copper layer. It is speculated that the difference in the size of the copper tumor is related to the uniformity of the charge distribution on the surface of the copper foil. The graphene stripping layer has ultra-high conductivity and two-dimensional continuity, which can provide a uniform distribution of horizontal current distribution during electrodeposition, reduce the interface impedance, and inhibit the peak value of the local current density, thereby reducing the abnormal aggregation of copper ions, and thus the size of the copper tumor is smaller. Figure 3

[0162] Figure 4 The separation force stability of the samples prepared in Example 1 and Comparative Examples 1-3 of the present application is compared, wherein (a) is Example 1; (b) is Comparative Example 1; (c) is Comparative Example 2; and (d) is Comparative Example 3. The separation force test is carried out according to IPC-TM-650 2.4.9. It can be seen from Figure 2 that the initial separation force of Example 1 is stable at 0.15-0.18 N / cm, and the attenuation rate is ≤8% after 50 cycles, the curve is smooth, and there is no mutation point, indicating that the interface bonding is uniform, which meets the requirements of high separation stability, controllable bonding force, and interface reliability, and is suitable for high-end flexible circuit boards. The initial separation force of Comparative Example 1 is too high, and the separation force decreases by 40% after 20 cycles, and the interface ages rapidly. The separation force of Comparative Example 2 fluctuates greatly, and abnormal peaks appear during the cycle. The initial separation force of Comparative Example 3 is too low, and the entire stripping layer is detached after 5 cycles. Figure 4 The separation performance and etching performance of the products of the above examples and comparative examples are tested, and the results are shown in Table 1 below:

[0163] Table 1 Comparison of separation performance and etching performance of samples of examples and comparative examples

[0164]

[0165]

[0166]

[0167] ​​From the data in Table 1, the average separation force of Examples 1-6 of the application is significantly lower than that of Comparative Examples 1-3, the range is significantly lower than that of Comparative Examples 1-3, the etching factor and etching efficiency of Examples 1-6 are significantly higher than those of Comparative Examples 1-3, indicating that the separation performance and etching performance of the two-component separation layer carrier copper foil of the application are superior to those of Comparative Examples 1-3.

[0168] The above examples only illustrate the principles and effects of the application, and are not intended to limit the application. Any person skilled in the art can modify or change the above examples without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed by the application should be covered by the claims of the application.

Claims

1. A method for preparing a two-component peeling layer carrier copper foil, characterized in that: The steps include: (1) preparing a carrier copper layer; (2) preparing a first inorganic release layer on the polished surface of the carrier copper layer by electrochemical / physical vapor deposition; (3) preparing a second inorganic peeling layer on the surface of the first inorganic peeling layer by a low-temperature chemical vapor deposition method; (4) preparing an extremely thin copper layer on the surface of the second inorganic stripping layer by a pulse electrochemical deposition method; (5) Roughening of the ultra-thin copper layer; (6) A non-copper functional layer is constructed on the surface of the roughened ultra-thin copper layer, and a silane coupling agent coating treatment is performed to obtain a two-component peeling layer carrier copper foil.

2. The method for preparing a two-component peelable layer carrier copper foil according to claim 1, wherein: In step (1), one or more of the following features are included: (a) the thickness of the carrier copper layer is 12-35 μm, and the surface roughness Rz of the carrier copper layer is between 0.9-1.5 μm; (b) A method for preparing a carrier copper layer comprises: using a titanium roller as a cathode, DSA as an anode, and acidic copper sulfate containing an additive as an electrolyte in an anode tank, and depositing a copper foil of uniform thickness and physical properties on the surface of the titanium cathode roller by direct current electrochemical deposition to obtain the carrier copper layer.

3. The method for preparing a two-component peelable layer carrier copper foil according to claim 2, wherein: In step (1), one or more of the following features are included: (b1) the thickness of the carrier copper layer is 18 μm; (b2) the additive is hydroxyethyl cellulose; (b3) the electrolyte comprises a copper ion concentration of 80-90 g / L, a sulfuric acid concentration of 120-150 g / L, a chloride ion concentration of 15-25 mg / L, and a hydroxyethyl cellulose concentration of 20-30 mg / L; (b4) The temperature of the electrolyte is 45-50°C, and the flow rate of the electrolyte is 40-45m 3 / h, current density is 7500-8500A / m 2 .

4. The method for preparing a two-component peeling layer carrier copper foil according to claim 1, wherein: Include one or more of the following characteristics: (a) In step (2), the first inorganic stripping layer is selected from nickel, nickel-based alloy, cobalt, cobalt-based alloy or molybdenum, and has a thickness of 8-12 nm; (b) In step (3), the second inorganic peeling layer is multilayer graphene with a thickness of 1-2 nm.

5. The method for preparing a two-component peeling layer carrier copper foil according to claim 4, wherein: Include one or more of the following characteristics: (a1) In step (2), the first inorganic stripping layer is nickel; the concentration of nickel ions in the electrolyte used for electrochemical deposition is 5-10 g / L, the concentration of potassium pyrophosphate is 150-200 g / L, the pH of the electrolyte is 10.0-10.5, the temperature of the electrolyte is 38-42°C, and the flow rate of the electrolyte is 5-10 m 3 / h, current density is 200-300A / m 2 ; (a2) In step (2), the physical vapor deposition is DC sputtering deposition, the target is a nickel target, the vacuum degree is 100-110 mTorr, the argon flow rate is 80-150 sccm, the sputtering power is 10-20 kW, and the sputtering time is 5-15 min; (b1) In step (3), the pressure of the low-temperature chemical vapor deposition is 40-60 Torr, the flow ratio of methane, argon and hydrogen is 1:3:1, the cooling rate is 10-15°C / s, the growth temperature is 800-950°C, and the growth time is 50-70 min.

6. The method for preparing a two-component peelable layer carrier copper foil according to claim 1, wherein: Include one or more of the following characteristics: (a) In step (4), the electrolyte used for the pulse electrochemical deposition has a copper ion concentration of 90-100 g / L, a sulfuric acid concentration of 125-150 g / L, a chloride ion concentration of 10-15 mg / L, and an additive concentration of 5-10 mg / L; (b) In step (4), the temperature of the electrolyte is 45-50°C, and the flow rate of the electrode liquid is 40-45m 3 / h, the average current density is 2000-2500A / m 2 , the duty cycle is 25%-33%; (c) in step (5), a pulse current is applied simultaneously during the roughening process; (d) In step (5), the copper ion concentration in the roughening electrolyte is 10-15 g / L, the sulfuric acid concentration is 90-120 g / L, and the additive is 10-20 mg / L; the electrolyte temperature is 25-30 ° C, and the electrolyte flow rate is 8-12 m 3 / h.

7. The method for preparing a two-component peelable layer carrier copper foil according to claim 6, wherein: Include one or more of the following characteristics: (a1) the additive is sodium 2-mercapto-5-benzimidazole sulfonate; (c1) The average current density of the pulse current is 500-800A / m 2 , the duty cycle is 15%-30%, the processing time is 8-12s, and the number of processing times is 2-3 times; (d1) The additive is sodium tungstate.

8. The method for preparing a two-component peelable layer carrier copper foil according to claim 1, wherein: Include one or more of the following characteristics: (a) In step (6), the construction of the non-copper functional layer includes sequentially preparing a nickel-based barrier layer and a zinc-chromium composite anti-oxidation layer on the surface of the roughened ultra-thin copper layer by a pulse electrochemical deposition method; (b) In step (6), the silane coupling agent is selected from KBM-503 or KBM-903, the concentration of the silane coupling agent is 0.5wt%-1.5wt%, and the flow rate of the silane coupling agent is 1.0-2.5m 3 / h, and then placed in an oven for baking after coating; (c) In step (6), a non-copper functional layer is constructed simultaneously on the matte surface of the carrier copper layer and the surface of the ultra-thin copper layer, and a silane coupling agent coating treatment is performed.

9. The method for preparing a two-component peelable layer carrier copper foil according to claim 8, wherein: Include one or more of the following characteristics: (a1) The electrolyte used for preparing the nickel-based barrier layer by pulse electrochemical deposition has a nickel ion concentration of 10-20 g / L, a boric acid concentration of 30-50 g / L, and a sodium hypophosphite concentration of 40-60 g / L; (a2) the zinc-chromium composite antioxidant layer comprises a zinc-based high-temperature antioxidant layer and a chromium-based normal-temperature antioxidant layer; the pulse electrochemical deposition of the zinc-chromium composite antioxidant layer comprises forming a zinc-based high-temperature antioxidant layer on the surface of the nickel-based barrier layer, and then forming a chromium-based normal-temperature antioxidant layer on the surface of the zinc-based high-temperature antioxidant layer; (a3) The temperature of the electrolyte used in the pulse electrochemical deposition to prepare the nickel-based barrier layer is 35-40°C, and the electrolyte flow rate is 5-10m 3 / h, average current density is 25-50A / m 2 , the duty cycle is 20%-33%, and the processing time is 8-12s; (b1) The baking temperature is 110-180°C.

10. A two-component peelable layer carrier copper foil prepared by the preparation method according to any one of claims 1 to 9.

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