A peelable ultra-thin carrier copper foil
By forming structures such as copper-nickel alloy layers and organic release layers on aluminum foil or polyimide films, the problem of high production costs of ultra-thin copper foil has been solved, and high-quality, low-cost preparation of ultra-thin copper foil has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIANGSU HENGTONG COPPER & ALUMINUM FOIL NEW MATERIALS RES INST CO LTD
- Filing Date
- 2025-08-15
- Publication Date
- 2026-08-04
AI Technical Summary
In the existing technology, the production cost of ultrathin copper foil is relatively high, and the surface roughness of the carrier copper foil has a significant impact on the quality of ultrathin copper foil, making it difficult to prepare high-quality ultrathin copper foil.
Using aluminum foil or polyimide film as a carrier, a copper-nickel alloy layer, an organic release layer, a copper foil, an oxide layer, and a copper particle layer are formed through magnetron sputtering and electroplating processes. The thickness and roughness of each layer are controlled to form a peelable ultrathin carrier copper foil.
This technology enables the low-cost preparation of high-quality ultrathin copper foil, simplifies the process, reduces production costs, and improves the peelability and surface roughness control of the copper foil.
Smart Images
Figure CN224591052U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of printed circuit board manufacturing technology, and in particular to a peelable ultrathin carrier copper foil. Background Technology
[0002] With the continuous development of electronic technology, people's requirements for electronic products are gradually trending towards shorter, smaller, lighter, and thinner designs. Correspondingly, printed circuit boards (PCBs), as an important component of electronic products, also need to develop towards multi-layering, density, and functionality, placing higher demands on the raw materials used to compose PCBs. Ultra-thin copper foil, as one of the key raw materials for PCBs, is a constraint on the further development of PCBs. The use of ultra-thin copper foil can not only meet the requirements of multi-layering and density in PCBs, but also improve the reliability of PCBs, reduce side etching problems in circuit etching, and lower the difficulty of laser etching.
[0003] Currently, ultrathin copper foil is mostly produced using a carrier copper foil method. The most basic structure of ultrathin copper foil consists of the ultrathin copper foil, a release layer, and a carrier. In existing technologies, copper foil is mainly used as a carrier to prepare ultrathin copper foil through electroplating. For example, patent application CN99101239.9 uses copper or copper alloy as a carrier to prepare ultrathin copper foil through electroplating; patent application CN01805265.7 uses copper as a carrier to prepare ultrathin copper foil through electrodeposition. Due to the "skin effect," high-frequency current will generate power loss when passing through the copper foil. Since the release layer and ultrathin copper foil are very thin, the surface roughness of the carrier layer has a significant impact on the ultrathin copper foil. Therefore, the surface of the carrier copper foil must undergo special treatment or the copper foil preparation process must be improved to achieve the goal of producing high-quality ultrathin copper foil. This inevitably increases the cost of producing ultrathin copper foil and hinders its development. Utility Model Content
[0004] In view of this, the technical problem to be solved by this utility model is to provide a peelable ultrathin carrier copper foil with low cost.
[0005] This utility model provides a peelable ultrathin carrier copper foil, comprising:
[0006] The carrier is an aluminum foil or a polyimide film.
[0007] A transition layer is formed on the carrier; the transition layer includes a plating layer a, and a copper metal layer formed on the plating layer a; the plating layer a is a copper-nickel alloy layer;
[0008] An organic peeling layer formed on the transition layer;
[0009] Copper foil formed on the organic release layer;
[0010] An oxide layer formed on the copper foil;
[0011] A copper particle layer formed on the oxide layer;
[0012] The surface roughness of the copper particle layer is Rz = 2~4 μm.
[0013] Preferably, the organic release layer is an ethylene glycol monomethyl ether layer.
[0014] Preferably, the thickness of the organic exfoliating layer is 20–3000 nm.
[0015] Preferably, the thickness of the coating a is 20-150 nm.
[0016] Preferably, the thickness of the copper metal layer is 2 to 4 μm.
[0017] Preferably, the thickness of the carrier is 20–100 μm.
[0018] Preferably, the thickness of the copper foil is 1 to 6 μm.
[0019] Preferably, the thickness of the oxide layer is 30–800 nm.
[0020] Preferably, the oxide layer is a copper oxide layer.
[0021] Preferably, the thickness of the copper particle layer is 1–3 μm.
[0022] This application provides a peelable ultrathin carrier copper foil, comprising: a carrier; the carrier being an aluminum foil or a polyimide film; a transition layer formed on the carrier; the transition layer including a plating layer a, and a copper metal layer formed on the plating layer a; the plating layer a being a copper-nickel alloy layer; an organic release layer formed on the transition layer; a copper foil formed on the organic release layer; an oxide layer formed on the copper foil; and a copper particle layer formed on the oxide layer; the surface roughness Rz of the copper particle layer being 2–4 μm. In this application, the layers can work well together to produce a peelable ultrathin carrier copper foil, with a simple process and low cost. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the structure of a peelable ultrathin carrier copper foil provided in one embodiment of this application. Detailed Implementation
[0024] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0025] This application provides a peelable ultrathin carrier copper foil, comprising:
[0026] The carrier is an aluminum foil or a polyimide film (PI film).
[0027] A transition layer is formed on the carrier; the transition layer includes a plating layer a, and a copper metal layer formed on the plating layer a; the plating layer a is a copper-nickel alloy layer;
[0028] An organic peeling layer formed on the transition layer;
[0029] Copper foil formed on the organic release layer;
[0030] An oxide layer formed on the copper foil;
[0031] A copper particle layer formed on the oxide layer;
[0032] The surface roughness of the copper particle layer is Rz = 2~4 μm.
[0033] Figure 1 This is a schematic diagram of the structure of a peelable ultrathin carrier copper foil provided in one embodiment of the present invention. Wherein, 1 is the carrier, 2 is the transition layer, 2-1 is plating layer a, 2-2 is the copper metal layer, 3 is the organic release layer, 4 is the copper foil, 5 is the oxide layer, and 6 is the copper particle layer.
[0034] In some embodiments of this utility model, the thickness of the carrier is 20-100 μm.
[0035] In some embodiments of this utility model, the copper-nickel alloy layer is a copper-nickel alloy B25 layer.
[0036] The thickness of the plating layer a is 20–150 nm, for example, 80 nm. The thickness of the copper metal layer is 2–4 μm, for example, 3 μm.
[0037] In some embodiments of this invention, the organic release layer is obtained by curing with an organic solvent. The organic solvent is ethylene glycol monomethyl ether. The thickness of the organic release layer is 20–3000 nm, for example, 2000 nm.
[0038] In some embodiments of this utility model, the thickness of the copper foil is 1 to 6 μm.
[0039] In some embodiments of this invention, the thickness of the oxide layer is 30–800 nm, for example, 200 nm.
[0040] The oxide layer is a copper oxide layer.
[0041] In some embodiments of this invention, the thickness of the copper particle layer is 1 to 3 μm, for example, 2 μm.
[0042] The surface roughness of the copper particle layer is Rz = 2.5 μm.
[0043] In this application, the peelable ultrathin carrier copper foil has a peel strength of 0.1 to 0.3 N / mm.
[0044] This utility model also provides a method for preparing the peelable ultrathin carrier copper foil described above, comprising the following steps:
[0045] A) A coating layer a is formed on the upper surface of the carrier using magnetron sputtering, and then a copper metal layer is deposited on the coating layer a using electroplating.
[0046] B) Coating the upper surface of the copper metal layer with an organic solvent, and after curing, forming an organic release layer;
[0047] C) Electroplating is used to deposit metallic copper on the organic stripping layer to obtain copper foil; oxidation and roughening treatments are performed on the upper surface of the copper foil to obtain an oxide layer and a copper particle layer.
[0048] Regarding step A):
[0049] A coating layer a is formed on the upper surface of a carrier using a magnetron sputtering process, and then a copper metal layer is deposited on the coating layer a using an electroplating process.
[0050] In some embodiments of this invention, the target material used in the magnetron sputtering process is a copper-nickel alloy; specifically, copper-nickel alloy B25. The atmosphere for magnetron sputtering is at least one of argon, nitrogen, and oxygen. The process parameters for magnetron sputtering include: a vacuum degree of 2 × 10⁻⁶. -1 ~3×10 -3 Pa, for example, 2×10 -1 Pa; plating rate is 1-10 m / min, for example 5 m / min; target current is 5-15 A, for example 12 A.
[0051] In some embodiments of this utility model, the electroplating process employs roll-to-roll multi-stage continuous electroplating. The parameters of the electroplating process include: plating speed of 1–5 m / min, for example, 3 m / min; and current density of 2–6 A / dm³. 2 For example, 4A / dm 2The plating solution temperature is 25-35℃, for example, 30℃; the pH value of the plating solution is 2-5, for example, 2.
[0052] The electroplating process uses a plating solution composed of copper sulfate, sulfuric acid, hydrochloric acid, and pure water. The copper sulfate content in the plating solution is 100–120 g / L, for example, 110 g / L; the sulfuric acid content is 130–160 g / L, for example, 140 g / L; and the hydrochloric acid content is 30–70 ppm, for example, 50 ppm.
[0053] Regarding step B):
[0054] An organic solvent is coated on the upper surface of the copper metal layer, and after curing, an organic release layer is formed.
[0055] In some embodiments of this invention, the organic solvent is ethylene glycol monomethyl ether.
[0056] Regarding step C):
[0057] Copper foil is obtained by depositing metallic copper on the organic release layer using an electroplating process; the upper surface of the copper foil is then subjected to oxidation and roughening treatment to obtain an oxide layer and a copper particle layer.
[0058] In some embodiments of this utility model, the electroplating process employs roll-to-roll multi-stage continuous electroplating. The parameters of the electroplating process include: plating speed of 2–4 m / min, for example, 3 m / min; and current density of 2–5 A / dm³. 2 For example, 3A / dm 2 The plating solution temperature is 25-30℃, for example, 28℃; the pH value of the plating solution is 2-5, for example, 3.
[0059] The electroplating process uses a plating solution composed of copper sulfate, sulfuric acid, hydrochloric acid, and pure water. The copper sulfate content in the plating solution is 100–120 g / L, for example, 110 g / L; the sulfuric acid content is 130–160 g / L, for example, 140 g / L; and the hydrochloric acid content is 30–70 ppm, for example, 50 ppm.
[0060] In some embodiments of this utility model, the oxidation treatment method includes:
[0061] The upper surface of the copper foil is immersed in an oxidizing agent solution.
[0062] The soaking time is 30 to 100 seconds, for example, 60 seconds.
[0063] The oxidizing agent solution comprises sodium persulfate, sulfuric acid, and water. The sodium persulfate content in the oxidizing agent solution is 10%–12% by mass, for example, 10%; the sulfuric acid content is 3%–5% by mass, for example, 3%.
[0064] In some embodiments of this utility model, the oxidation treatment further includes: washing with water and drying until winding.
[0065] In some embodiments of this utility model, the roughening treatment method is roughening electroplating, specifically including:
[0066] A roughening electroplating process is used to electroplat a layer of copper metal particles with high roughness onto the oxide layer.
[0067] The process parameters for the roughening electroplating include:
[0068] The plating rate is 2–5 m / min, for example, 2 m / min; the current density is 3–8 A / dm. 2 For example, 3A / dm 2 The plating solution temperature is 30-40℃, for example, 30℃; the pH value of the plating solution is 2-5, for example, 3.
[0069] A roughening electroplating process is used, employing a copper foil post-processing machine to electroplat copper microparticles.
[0070] This invention does not impose any special restrictions on the source of the raw materials used above, and they can be commercially available.
[0071] This invention uses aluminum foil as a carrier, which can reduce production costs.
[0072] This invention uses magnetron sputtering to prepare a transition layer and a special organic solvent to form an organic release layer. The transition layer and the organic release layer can work well with other layers to produce a peelable ultrathin carrier copper foil. The process is simple, the cost is low, and it is easy to peel off.
[0073] To further illustrate this utility model, the following detailed description of a peelable ultrathin carrier copper foil provided by this utility model is provided in conjunction with embodiments, but it should not be construed as a limitation on the scope of protection of this utility model.
[0074] Example 1
[0075] Preparation of peelable ultrathin carrier copper foil:
[0076] 1) Select a carrier (aluminum foil) with a thickness of 30μm, a width of 1040mm, and a length of 1000m;
[0077] 2) In a vacuum chamber, magnetron sputtering is performed on the surface of a carrier, using a copper-nickel alloy B25 target to form a copper-nickel alloy B25 layer (i.e., coating a); the process parameters for the magnetron sputtering include: a vacuum degree of 2 × 10⁻⁶. -1 Pa, plating rate of 5 m / min, target current of 12 A, gas atmosphere of argon; the thickness of the plating layer a is 80 nm;
[0078] 3) On the plating layer a, copper metal is electroplated using a roll-to-roll multi-stage continuous electroplating line to obtain a copper metal layer; the parameters of the electroplating process include: plating rate of 3 m / min and current density of 4 A / dm³. 2 The plating solution temperature is 30℃, and the pH value is 2. The plating solution components used in the electroplating process include copper sulfate, sulfuric acid, hydrochloric acid, and pure water. The copper sulfate content in the plating solution is 110 g / L, the sulfuric acid content is 140 g / L, and the hydrochloric acid content is 50 ppm. The thickness of the copper metal layer is 3 μm, forming a stripped metal layer.
[0079] 4) Coat the upper surface of the copper metal layer with an organic solvent (ethylene glycol monomethyl ether), and after curing, form an organic release layer; the thickness of the organic release layer is 2000 nm;
[0080] 5) On the organic release layer, metallic copper is electroplated on a roll-to-roll multi-stage continuous electroplating line to obtain a copper foil with a thickness of 4 μm; the parameters of the electroplating process include: plating rate of 3 m / min and current density of 3 A / dm³. 2 The plating solution temperature is 28℃, and the pH value is 3. The plating solution components used in the electroplating process include: copper sulfate, sulfuric acid, hydrochloric acid, and pure water. The copper sulfate content in the plating solution is 110 g / L, the sulfuric acid content is 140 g / L, and the hydrochloric acid content is 50 ppm.
[0081] The upper surface of the copper foil is subjected to an oxidation treatment:
[0082] The upper surface of the copper foil is immersed in an oxidizing agent solution for 60 seconds. The oxidizing agent solution comprises sodium persulfate, sulfuric acid, and water. The sodium persulfate content in the oxidizing agent solution is 10% by mass, and the sulfuric acid content is 3% by mass.
[0083] After being washed, dried and wound up, a layer of high-roughness copper metal particles is electroplated onto the oxide layer using a roughening electroplating process.
[0084] The process parameters for the roughening electroplating include:
[0085] Plating rate: 2 m / min; Current density: 3 A / dm 2 The plating solution temperature is 30℃, and the pH value of the plating solution is 3.
[0086] An oxide layer (200 nm thick) and a copper particle layer (2 μm thick) formed on the oxide layer are obtained. The roughness of the copper particle layer is 2.5 μm.
[0087] The peelable ultrathin carrier copper foil was tested using a peel strength tester (model TH3000). The results showed that the peel strength of the peelable ultrathin carrier copper foil was 0.2 N / mm.
[0088] Example 2
[0089] The difference from Example 1 is as follows:
[0090] The carrier aluminum foil in Example 1 was replaced with a PI film, and the remaining steps were the same as in Example 1, to obtain a peelable ultrathin carrier copper foil.
[0091] The peelable ultrathin carrier copper foil was tested using a peel strength tester (model TH3000). The results showed that the peel strength of the peelable ultrathin carrier copper foil was 0.1 N / mm.
[0092] Comparative Example 1
[0093] The difference from Example 1 is as follows:
[0094] In step 1), the carrier aluminum foil in Example 1 is replaced with copper foil, and the remaining steps are the same as in Example 1, to obtain a peelable ultrathin carrier copper foil.
[0095] Compared to Example 1, the cost of the peelable ultrathin carrier copper foil prepared in Comparative Example 1 is 6-9 yuan / square meter higher. Compared to Example 2, the cost of the peelable ultrathin carrier copper foil prepared in Comparative Example 1 is 3-5 yuan / square meter higher.
[0096] Comparative Example 2
[0097] In step 4), the organic solvent is replaced with ethanol, and the remaining steps are the same as in Example 1, to obtain a peelable ultrathin carrier copper foil.
[0098] The peelable ultrathin carrier copper foil was tested using a peel strength tester (model TH3000). The results showed that the peel strength of the peelable ultrathin carrier copper foil was 0.07 N / mm.
[0099] The above description of the embodiments is merely to aid in understanding the method and core ideas of this utility model. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this utility model. Therefore, this utility model is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A peelable ultra-thin carrier copper foil, characterized by, include: The carrier is an aluminum foil or a polyimide film. A transition layer is formed on the carrier; the transition layer includes a plating layer a, and a copper metal layer formed on the plating layer a; the plating layer a is a copper-nickel alloy layer; An organic peeling layer formed on the transition layer; Copper foil formed on the organic release layer; An oxide layer formed on the copper foil; A copper particle layer formed on the oxide layer; The surface roughness of the copper particle layer is Rz = 2~4 μm.
2. The peelable ultra-thin carrier copper foil according to claim 1, wherein, The organic stripping layer is an ethylene glycol monomethyl ether layer.
3. The peelable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the organic exfoliating layer is 20–3000 nm.
4. The peelable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the coating layer a is 20–150 nm.
5. The strippable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the copper metal layer is 2–4 μm.
6. The peelable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the carrier is 20–100 μm.
7. The strippable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the copper foil is 1–6 μm.
8. The strippable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the oxide layer is 30–800 nm.
9. The peelable ultrathin carrier copper foil according to claim 1, characterized in that, The oxide layer is a copper oxide layer.
10. The strippable ultra-thin carrier copper foil according to claim 1, wherein, The thickness of the copper particle layer is 1–3 μm.