Preparation method of three-dimensional skeleton enhanced aluminum foil of magnetron sputtering nano-copper coating film

Abstract

The invention discloses a preparation method of a three-dimensional skeleton enhanced aluminum foil of a magnetron sputtering nano-copper coating film, and belongs to the technical field of copper foil surface treatment. The preparation method of the three-dimensional skeleton enhanced aluminum foil of the magnetron sputtering nano-copper coating film comprises the following steps: putting an aluminum foil substrate into an ultrasonic cleaning machine, immersing the aluminum foil substrate in an isopropanol solution for cleaning, then putting the aluminum foil substrate into stronger ammonia water for soaking to obtain an aluminum foil substrate with a three-dimensional skeleton structure, carrying out magnetron sputtering on the aluminum foil substrate, using an ultra-high-purity copper target material, and after deposition is finished, preparing the three-dimensional skeleton enhanced aluminum foil of the magnetron sputtering nano-copper coating film. And carrying out post-treatment to finally obtain the three-dimensional skeleton reinforced aluminum foil of the magnetron sputtering nano-copper coating film. The three-dimensional skeleton enhanced aluminum foil of the magnetron sputtering nano-copper coating film has excellent bonding strength.

Description

Technical Field

[0001] The invention belongs to the technical field of copper foil surface treatment, and in particular relates to a method for preparing a three-dimensional skeleton-enhanced aluminum foil of magnetron sputtering nano-copper plating. Background Art

[0002] Aluminum foil is widely used in many fields such as packaging and electronics. In the packaging field, it has good barrier properties and can effectively prevent the penetration of substances such as oxygen and water vapor, thereby extending the shelf life of products such as food and medicine. In the electronics field, aluminum foil can be used in the manufacture of electronic components such as capacitors because aluminum has good conductivity.

[0003] Aluminum foil with a three-dimensional skeleton structure refers to an aluminum foil material with a three-dimensional skeleton structure, which makes the aluminum foil thin and light while having excellent strength and stability. Its unique structural characteristics give the aluminum foil material a series of excellent properties, such as high thermal conductivity, high strength, good mechanical properties and processability.

[0004] Therefore, the present invention develops a method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating, which is used to solve the technical problem of insufficient bonding strength between the aluminum foil and the nano-copper layer in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating, so as to solve the technical problem of insufficient bonding strength between the aluminum foil and the nano-copper layer in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The method for preparing a three-dimensional skeleton-enhanced aluminum foil by magnetron sputtering nano-copper coating comprises the following steps: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning. After cleaning, rinse it with deionized water and place it in an oven to dry to obtain a clean aluminum foil substrate. (2) Preparing aluminum foil with a three-dimensional skeleton structure: soaking a clean aluminum foil substrate in concentrated ammonia water, rinsing it with deionized water, and drying it in an oven again to obtain an aluminum foil substrate with a three-dimensional skeleton structure; (3) Magnetron sputtering: prepare ultra-high purity copper target, start the vacuum pump, evacuate the sputtering chamber to the working vacuum degree, introduce argon gas into the sputtering chamber, install the ultra-high purity copper target, set the power of the sputtering power supply, adjust the distance between the target and the substrate, set the pre-sputtering time, perform pre-sputtering, and then start the sputtering power supply to start depositing the nano-copper coating. After completion, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate is annealed under argon and cooled to room temperature, and finally rinsed with deionized water and placed in an oven for drying to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

[0007] Furthermore, in step (1), the cleaning time is 10-15 minutes, the oven drying temperature is 60-80°C, and the drying time is 30-60 minutes; in step (2), the soaking time is 3-50 hours, the oven drying temperature is 60-80°C, and the drying time is 30-60 minutes; in step (3), the impurity element content of the ultra-high purity copper target is ≤20ppm, and the working vacuum degree is 10 -6 -10 - 9 Pa, the argon gas flow rate is 20-30sccm, the power of the sputtering power supply is 20-200W, the distance between the target and the substrate is 5-10cm, the pre-sputtering time is 5-10 minutes, the thickness of the nano copper coating is 30-800nm, and the deposition time is 10-30 minutes; in step (4), the annealing temperature is 200-300°C, the annealing time is 10-30 minutes, the oven drying temperature is 60-80°C, and the drying time is 30-60min.

[0008] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention removes oil stains and impurities on the surface of the aluminum foil substrate by placing an aluminum foil substrate in an ultrasonic cleaning machine and immersing it in an isopropyl alcohol solution for cleaning; then immersing it in concentrated ammonia water, which can promote the oxidation reaction on the surface of the aluminum foil. The ammonia water reacts with the aluminum oxide on the surface of the aluminum foil to generate aluminum hydroxide, thereby increasing the roughness and specific surface area of ​​the surface of the aluminum foil substrate and forming a three-dimensional skeleton structure. The three-dimensional skeleton structure can provide more attachment sites, enhance the adhesion of the copper plating, and thus improve the bonding strength between the aluminum foil and the nano copper plating.

[0009] 2. The present invention performs pre-sputtering for 5-10 minutes to clean the target surface; uses an ultra-high purity copper target with an impurity element content of ≤20 ppm to ensure the high purity of the copper layer. The high-purity copper target can reduce the introduction of impurity elements and avoid the reduction of conductivity and corrosion resistance. The reduction of impurity elements can also avoid the performance degradation of the copper layer under high temperature and corrosive environment; the magnetron sputtering technology precisely controls the deposition power, gas flow, distance and time, thereby achieving control of the copper layer deposition quality, and obtaining a three-dimensional skeleton-reinforced aluminum foil with excellent bonding strength and magnetron sputtered nano-copper coating. DETAILED DESCRIPTION

[0010] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0011] Embodiment 1: The method for preparing a three-dimensional skeleton-enhanced aluminum foil by magnetron sputtering nano-copper coating comprises the following steps: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning for 10 minutes. After cleaning, rinse it with deionized water and place it in an oven for drying at 60°C for 30 minutes to obtain a clean aluminum foil substrate. (2) Preparation of aluminum foil with a three-dimensional skeleton structure: soak the clean aluminum foil substrate in concentrated ammonia water for 3 hours. After soaking, rinse it with deionized water and put it in an oven for drying again. The oven drying temperature is 60°C and the drying time is 30 minutes to obtain an aluminum foil substrate with a three-dimensional skeleton structure. (3) Magnetron sputtering: Prepare ultra-high purity copper target with impurity element content ≤ 20 ppm, start the vacuum pump, and evacuate the sputtering chamber to the working vacuum degree of 10 -6 Pa, argon gas is introduced into the sputtering chamber, the argon gas flow rate is 20sccm, an ultra-high purity copper target is installed, the power of the sputtering power supply is set to 20W, the distance between the target and the substrate is adjusted to 5cm, the pre-sputtering time is set to 5 minutes, pre-sputtering is performed, and then the sputtering power supply is started to start depositing the nano copper coating, the deposition time is 10 minutes, and after the end, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate was annealed under argon at a temperature of 200°C for 10 minutes, cooled to room temperature, and finally rinsed with deionized water and placed in an oven for drying at a temperature of 60°C for 30 minutes to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

[0012] Embodiment 2: The method for preparing a three-dimensional skeleton-enhanced aluminum foil by magnetron sputtering nano-copper coating comprises the following steps: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning for 12 minutes. After cleaning, rinse it with deionized water and place it in an oven for drying at 70°C for 40 minutes to obtain a clean aluminum foil substrate. (2) Preparation of aluminum foil with a three-dimensional skeleton structure: soaking a clean aluminum foil substrate in concentrated ammonia water for 3-50 hours. After soaking, rinse with deionized water and put it in an oven for drying again. The oven drying temperature is 70°C and the drying time is 40 minutes to obtain an aluminum foil substrate with a three-dimensional skeleton structure. (3) Magnetron sputtering: Prepare ultra-high purity copper target with impurity element content ≤ 20 ppm, start the vacuum pump, and evacuate the sputtering chamber to the working vacuum degree of 10 -7 Pa, argon gas is introduced into the sputtering chamber, the argon gas flow rate is 20sccm, an ultra-high purity copper target is installed, the power of the sputtering power supply is set to 100W, the distance between the target and the substrate is adjusted to 6cm, the pre-sputtering time is set to 6 minutes, pre-sputtering is performed, and then the sputtering power supply is started to start depositing the nano copper coating, the deposition time is 18 minutes, and after the end, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate was annealed under argon at a temperature of 250°C for 18 minutes, cooled to room temperature, and finally rinsed with deionized water and dried in an oven at a temperature of 65°C for 55 minutes to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

[0013] Embodiment 3: The method for preparing a three-dimensional skeleton-enhanced aluminum foil by magnetron sputtering nano-copper coating comprises the following steps: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning for 14 minutes. After cleaning, rinse it with deionized water and place it in an oven for drying at a temperature of 75°C for 50 minutes to obtain a clean aluminum foil substrate. (2) Preparation of aluminum foil with a three-dimensional skeleton structure: soaking a clean aluminum foil substrate in concentrated ammonia water for 3-50 hours. After soaking, rinse with deionized water and put it in an oven for drying again. The oven drying temperature is 75°C and the drying time is 50 minutes to obtain an aluminum foil substrate with a three-dimensional skeleton structure. (3) Magnetron sputtering: Prepare ultra-high purity copper target with impurity element content ≤ 20 ppm, start the vacuum pump, and evacuate the sputtering chamber to the working vacuum degree of 10 -8 Pa, argon gas is introduced into the sputtering chamber, the argon gas flow rate is 28sccm, an ultra-high purity copper target is installed, the power of the sputtering power supply is set to 180W, the distance between the target and the substrate is adjusted to 8cm, the pre-sputtering time is set to 8 minutes, pre-sputtering is performed, and then the sputtering power supply is started to start depositing the nano copper coating, the deposition time is 20 minutes, and after the end, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate is annealed under argon at a temperature of 270°C for 10-30 minutes, cooled to room temperature, and finally rinsed with deionized water and placed in an oven for drying at a temperature of 70°C for 50 minutes to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

[0014] Embodiment 4: The method for preparing a three-dimensional skeleton-enhanced aluminum foil by magnetron sputtering nano-copper coating comprises the following steps: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning for 15 minutes. After cleaning, rinse it with deionized water and place it in an oven for drying at 80°C for 60 minutes to obtain a clean aluminum foil substrate. (2) Preparation of aluminum foil with a three-dimensional skeleton structure: The clean aluminum foil substrate was immersed in concentrated ammonia water for 50 hours. After immersion, it was rinsed with deionized water and dried in an oven again at a temperature of 80°C for 60 minutes to obtain an aluminum foil substrate with a three-dimensional skeleton structure. (3) Magnetron sputtering: Prepare ultra-high purity copper target with impurity element content ≤ 20 ppm, start the vacuum pump, and evacuate the sputtering chamber to the working vacuum degree of 10 -9 Pa, argon gas is introduced into the sputtering chamber, the argon gas flow rate is 30sccm, an ultra-high purity copper target is installed, the power of the sputtering power supply is set to 200W, the distance between the target and the substrate is adjusted to 10cm, the pre-sputtering time is set to 10 minutes, pre-sputtering is performed, and then the sputtering power supply is started to start depositing the nano copper coating, the deposition time is 30 minutes, and after the end, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate was annealed under argon at a temperature of 300°C for 30 minutes, cooled to room temperature, and finally rinsed with deionized water and placed in an oven for drying at a temperature of 80°C for 60 minutes to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

[0015] Comparative Example 1: Comparative Example 1 Compared with Example 4, in the preparation process of the three-dimensional skeleton-enhanced aluminum foil with nano-copper coating by magnetron sputtering, Comparative Example 1 was not immersed in concentrated ammonia water, and other conditions remained unchanged.

[0016] Comparative Example 2: Comparative Example 2 Compared with Example 4, in the preparation process of the three-dimensional skeleton-enhanced aluminum foil with magnetron sputtering nano-copper coating, no annealing treatment was performed in Comparative Example 2, and other conditions remained unchanged.

[0017] Experimental example: Adhesion test was performed on the three-dimensional skeleton-enhanced aluminum foil samples of the magnetron sputtering nano-copper coating prepared in Examples 1-4 and Comparative Examples 1-2: The adhesion between the nano copper plating and the aluminum foil is measured by the 100-grid test method. The details are as follows: use a 100-grid knife to cut through the film layer, then stick the 3M tape on the 100-grid test area, press it flat with your fingers to ensure that there are no bubbles, and after the tape and the product form about 90 degrees, pull it quickly and forcefully, test 3 times, and check the integrity of the film layer in the 100-grid area. The adhesion grade judgment criteria are as follows: 5B if there is no shedding of the film layer, 4B if the shedding surface of the film layer is less than 5%, 3B if the shedding area of ​​the film layer is 5%-15%, 2B if the shedding area of ​​the film layer is 15%-35%, 1B if the shedding area of ​​the film layer is 35%-65%, and 0B if the shedding area of ​​the film layer exceeds 65%. The test results are shown in Table 1:

[0018] Table 1 Group Adhesion grade Example 1 5B Example 2 5B Example 3 5B Example 4 5B Comparative Example 1 1B Comparative Example 2 2B According to the test results in Table 1, the three-dimensional skeleton-enhanced aluminum foil with nano-copper coating by magnetron sputtering prepared in Examples 1-4 of the present invention has strong adhesion. By comparing Comparative Examples 1-2 with Examples 1-4, it can be seen that soaking in concentrated ammonia water and annealing can enhance the bonding strength of the three-dimensional skeleton-enhanced aluminum foil with nano-copper coating by magnetron sputtering.

[0019] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0020] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating, characterized in that: The following steps are involved: (1) Cleaning and drying: Place the aluminum foil substrate in an ultrasonic cleaning machine and immerse it in an isopropanol solution for cleaning. After cleaning, rinse it with deionized water and place it in an oven to dry to obtain a clean aluminum foil substrate. (2) Preparing aluminum foil with a three-dimensional skeleton structure: soaking a clean aluminum foil substrate in concentrated ammonia water, rinsing it with deionized water, and drying it in an oven again to obtain an aluminum foil substrate with a three-dimensional skeleton structure; (3) Magnetron sputtering: prepare ultra-high purity copper target, start the vacuum pump, evacuate the sputtering chamber to the working vacuum degree, introduce argon gas into the sputtering chamber, install the ultra-high purity copper target, set the power of the sputtering power supply, adjust the distance between the target and the substrate, set the pre-sputtering time, perform pre-sputtering, and then start the sputtering power supply to start depositing the nano-copper coating. After completion, a deposited aluminum foil substrate is obtained; (4) Post-treatment: The deposited aluminum foil substrate is annealed under argon and cooled to room temperature, and finally rinsed with deionized water and placed in an oven for drying to obtain a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating.

2. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: In step (1), the cleaning time is 10-15 minutes, the oven drying temperature is 60-80°C, and the drying time is 30-60 minutes.

3. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: In step (2), the soaking time is 3-50 hours, the oven drying temperature is 60-80° C., and the drying time is 30-60 minutes.

4. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: The impurity element content of the ultra-high purity copper target in step (3) is ≤20ppm.

5. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: The working vacuum degree in step (3) is 10 -6 -10 -9 Pa, and the argon gas flow rate is 20-30 sccm.

6. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: In step (3), the power of the sputtering power source is 20-200 W, the distance between the target and the substrate is 5-10 cm, and the pre-sputtering time is 5-10 minutes.

7. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: The thickness of the nano copper coating in step (3) is 30-800 nm, and the deposition time is 10-30 minutes.

8. The method for preparing a three-dimensional skeleton-enhanced aluminum foil with a magnetron sputtering nano-copper coating according to claim 1, characterized in that: In step (4), the annealing temperature is 200-300°C, the annealing time is 10-30 minutes, the oven drying temperature is 60-80°C, and the drying time is 30-60 minutes.