Target material cleaning method

Abstract

The invention relates to a target material cleaning method, in particular to the technical field of target material cleaning, and the target material cleaning method comprises the following steps: sequentially carrying out dust removal, composite oil removal, water washing and alcohol washing on a target material to obtain a cleaned target material; an oil removal agent used in the composite oil removal process comprises the following components in percentage by mass: 3-5% of polyoxyethylene ether, 0.5-1% of an amino carboxylic acid compound and the balance of a solvent. According to the cleaning method provided by the invention, the composition of the degreasing agent is optimized, and the oil stain impurities on the target material can be effectively removed by virtue of the synergistic effect of polyoxyethylene ether and aminocarboxylic acid compounds, so that the efficient cleaning of the target material is realized.

Description

Technical Field

[0001] This invention relates to the field of target cleaning technology, specifically to a target cleaning method, and more particularly to a method for cleaning targets obtained by powder metallurgy. Background Technology

[0002] Currently, as the core material for sputtering coating, the surface cleanliness of the target material directly affects the uniformity and conductivity of the coating layer. Most existing targets are prepared using powder metallurgy processes.

[0003] For example, CN108611607A discloses a powder metallurgy method and a method for forming a target material. The powder metallurgy method includes: providing powder; performing hot isostatic pressing (HIP) on the powder to form a billet; and annealing the billet to form a finished product. The annealing treatment is performed after the HIP treatment of the powder. The annealing treatment allows the billet to recrystallize and promotes grain growth, increasing the density of the formed finished product. Simultaneously, the annealing treatment reduces the stress generated in the billet during the HIP treatment, reduces defects in the billet, and thus improves the performance of the formed finished product.

[0004] CN117265486A discloses a method for preparing FeCrAl targets using powder metallurgy. The FeCrAl targets prepared by powder metallurgy are prepared by hot isostatic pressing. The method includes the following preparation steps: Step (1) Powder preparation and inert gas protection powder mixing: Prepare high-purity pre-made Fe powder, Cr powder, and Al powder, mix the powders according to the target material composition, and mix the powders under inert gas Ar; Step (2) Encasing welding and degassing: Design and manufacture the casing according to the size of the formed target material, evacuate the casing at high temperature in a heat treatment furnace, and prepare the FeCrAl targets by using hot isostatic pressing in powder metallurgy.

[0005] However, after powder metallurgy forming, the surface and internal micropores of the target material are prone to residual forming aids, cutting oil stains and metal dust. Traditional single ultrasonic cleaning cannot completely remove contaminants in the micropores. It can be seen that the existing technology for cleaning the target material obtained by powder metallurgy still has the defect of not being able to effectively remove the contaminants remaining in the target material preparation process, which makes the uniformity and conductivity of the obtained coating worse. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a target cleaning method to solve the defect that the residual contaminants in the target preparation process cannot be effectively removed when cleaning the target obtained by powder metallurgy, resulting in poor uniformity and conductivity of the obtained coating.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This invention provides a target cleaning method, the target cleaning method comprising:

[0009] The target material is subjected to dust removal, composite degreasing, water washing and alcohol washing in sequence to obtain a clean target material;

[0010] The degreasing agent used in the composite degreasing process comprises, by mass percentage: 3-5% polyoxyethylene ether, 0.5-1% aminocarboxylic acid compound, and the balance being solvent.

[0011] The cleaning method provided by this invention optimizes the composition of the degreasing agent, and with the synergistic effect of polyoxyethylene ether and aminocarboxylic acid compounds, it can effectively remove oil and impurities on the target material, which is conducive to achieving efficient cleaning of the target material.

[0012] As a preferred technical solution of the present invention, the cleaning process of the target material is carried out in a closed environment with a pressure of 0.08-0.12MPa.

[0013] Preferably, during the cleaning process of the target material, a protective gas is continuously supplied at an airflow velocity of 0.5-1 m / s.

[0014] Preferably, the dust removal temperature is 25-30℃.

[0015] Preferably, the dust removal process is supplemented with ultrasound with a power of 20-25W and a frequency of 18-20kHz.

[0016] Preferably, the dust removal time is 10-15 minutes.

[0017] As a preferred embodiment of the present invention, the aminocarboxylic acid compound includes one or a combination of at least two of EDTA, EDTA salt, EDDA, ​​EDDA salt, IDA, or IDA salt.

[0018] As a preferred technical solution of the present invention, the temperature of the composite degreasing is 40-45℃.

[0019] Preferably, the combined degreasing time is 13-20 minutes.

[0020] As a preferred technical solution of the present invention, the composite degreasing process is supplemented by ultrasound with a power of 30-35W and a frequency of 28-32kHz.

[0021] As a preferred technical solution of the present invention, the water washing includes: rinsing and spray washing performed sequentially.

[0022] As a preferred technical solution of the present invention, the rinsing is supplemented with ultrasound with a power of 25-30W and a frequency of 40-45kHz.

[0023] Preferably, the rinsing temperature is 45-50°C.

[0024] Preferably, the rinsing time is 6-8 minutes.

[0025] Preferably, the temperature of the spray washing is 35-40℃.

[0026] Preferably, the spray pressure of the spray washing is 0.15-0.2 MPa.

[0027] Preferably, the nozzles in the spray washing process rotate at 10-15 r / min.

[0028] Preferably, the spray washing time is 18-22 seconds.

[0029] As a preferred technical solution of the present invention, the alcohol washing includes: a first-stage alcohol washing, a second-stage alcohol washing, and a third-stage alcohol washing performed sequentially.

[0030] As a preferred technical solution of the present invention, the alcohol solution used in the alcohol washing includes: ethanol solution and / or isopropanol solution.

[0031] Preferably, the mass concentration of the alcohol solution used in the first-stage alcohol washing is 92-96%.

[0032] Preferably, the temperature of the first-stage alcohol washing is 30-35°C.

[0033] Preferably, the primary alcohol washing time is 4-6 minutes.

[0034] Preferably, the mass concentration of the alcohol solution used in the secondary alcohol washing is ≥99.9%.

[0035] Preferably, the secondary alcohol washing is supplemented with ultrasound with a power of 15-20W and a frequency of 12-15kHz.

[0036] Preferably, the temperature of the secondary alcohol washing is 30-35°C.

[0037] Preferably, the operating humidity during the secondary alcohol washing is controlled to be ≤30%.

[0038] Preferably, the secondary alcohol washing time is 3-5 minutes.

[0039] Preferably, the three-stage alcohol washing is carried out under an alcohol atmosphere.

[0040] Preferably, the temperature of the three-stage alcohol washing is 40-45°C.

[0041] Preferably, the time for the three-stage alcohol washing is 2-3 minutes.

[0042] As a preferred technical solution of the present invention, the alcohol washing is followed by drying.

[0043] Preferably, the drying process includes a first drying and a second drying performed sequentially.

[0044] Preferably, the temperature of the first drying is 45-50°C.

[0045] Preferably, the wind speed of the drying gas in the first drying process is 1.5-2 m / s.

[0046] Preferably, the humidity of the drying gas in the first drying process is ≤20%.

[0047] Preferably, the first drying time is 3-4 minutes.

[0048] Preferably, the temperature of the second drying is 55-60°C.

[0049] Preferably, the wind speed of the drying gas in the second drying process is 1.5-2 m / s.

[0050] Preferably, the humidity of the drying gas in the first drying process is ≤20%.

[0051] Preferably, the second drying time is 2-3 minutes.

[0052] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0053] (1) The cleaning method provided by the present invention adapts the ultrasonic frequency gradient during the cleaning process and adopts the gradient frequency of "low frequency dust removal - medium frequency oil removal - high frequency rinsing" to strengthen the directional cleaning of micropores, thereby solving the problem of difficult removal of pollutants in the micropores of powder metallurgy targets and ensuring the efficient removal of pollutants at different depths.

[0054] (2) In the cleaning method provided by the present invention, gas protection is carried out throughout the entire process. From pretreatment to drying and cooling, high-purity protective gas is introduced throughout the process. On the one hand, it prevents the target material from oxidizing during the cleaning process, and on the other hand, it can help remove volatile pollutants and moisture, thereby improving the cleaning efficiency.

[0055] (3) The cleaning method provided by the present invention adopts a low temperature control system to control the cleaning and drying temperature in the range of 30-60℃, which is lower than the 70-80℃ of the traditional cleaning process, effectively reducing the impact of high temperature on the brittleness of the target material and reducing the risk of breakage.

[0056] (4) The cleaning method provided by the present invention further removes contaminants in the micropores of powder metallurgy target material through a combination of rotary spraying and alcohol vapor bath process, ensuring that the surface and interior of the target material are clean. After cleaning, the surface oil residue of the target material is ≤0.5mg / m², the number of microparticles (particle size ≥0.5μm) is ≤5 / cm², and there are no cracks or defects, which meets the cleanliness requirements of semiconductor sputtering target material.

[0057] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0058] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0059] Currently, powder metallurgy is one of the methods for preparing sputtering targets. However, the surface and internal micropores of targets obtained by powder metallurgy are prone to residual forming aids, cutting oil stains, and metal dust. In order to ensure the final performance of the target, it is necessary to clean the target before use to remove the impurities remaining on the target surface and inside the micropores. However, current cleaning methods, such as alcohol washing, water washing, and ultrasonic assistance, still cannot effectively remove impurities from powder metallurgy targets. Based on this, the present invention optimizes the existing cleaning method by compounding the cleaning agent used in the cleaning process to improve the cleaning effect, and further optimizes the cleaning process to improve the overall cleaning effect, as detailed below:

[0060] I. This embodiment provides a target cleaning method, the target cleaning method comprising:

[0061] The target material is subjected to dust removal, composite degreasing, water washing, and alcohol washing in sequence to obtain a clean target material.

[0062] In this invention, the target material can be selected from the target material field by powder metallurgy, such as pure targets such as chromium, niobium, vanadium, and tungsten, alloy targets such as titanium aluminum, nickel chromium, and aluminum titanium silicon, and ceramic targets such as tungsten carbide, titanium boride, and indium tin oxide (ITO). This invention is particularly applicable to related targets with brittleness greater than or equal to tungsten targets, and can avoid damage to brittle targets. Specifically, it can be selected as the corresponding high-purity target or ultra-high-purity target.

[0063] In this invention, the high purity refers to a purity of ≥99.99%.

[0064] In this invention, the ultra-high purity is ≥99.9999%.

[0065] The cleaning process of the target material is carried out in a closed environment with a pressure of 0.08-0.12 MPa, such as 0.08 MPa, 0.085 MPa, 0.09 MPa, 0.095 MPa, 0.1 MPa, 0.103 MPa, 0.107 MPa, 0.11 MPa, 0.113 MPa, 0.117 MPa or 0.12 MPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0066] In this invention, the entire cleaning process of the target material, including dust removal, composite degreasing, water washing and alcohol washing, is carried out in a closed environment with a pressure of 0.08-0.12 MPa.

[0067] During the cleaning process of the target material, a protective gas is continuously supplied at an airflow velocity of 0.5-1 m / s.

[0068] In this invention, the protective gas refers to a gas that does not react with the target material during the cleaning process, such as nitrogen, helium, neon, argon, carbon dioxide, etc. The specific gas to be selected depends on the material of the target material being cleaned.

[0069] In this invention, the entire cleaning process of the target material, including dust removal, composite degreasing, water washing and alcohol washing, is carried out with a continuous supply of protective gas at an airflow velocity of 0.5-1 m / s.

[0070] The dust removal temperature is 25-30℃, for example, it can be 25℃, 25.5℃, 26℃, 26.5℃, 27℃, 27.5℃, 28℃, 28.5℃, 29℃, 29.5℃ or 30℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0071] The dust removal process is supplemented with ultrasound with a power of 20-25W and a frequency of 18-20kHz. The power can be, for example, 20W, 20.5W, 21W, 21.5W, 22W, 22.5W, 23W, 23.5W, 24W, 24.5W, or 25W, and the frequency can be, for example, 18kHz, 18.2kHz, 18.4kHz, 18.6kHz, 18.8kHz, 19kHz, 19.2kHz, 19.4kHz, 19.6kHz, 19.8kHz, or 20kHz, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0072] The dust removal time is 10-15 minutes, for example, it can be 10 minutes, 10.5 minutes, 11 minutes, 11.5 minutes, 12 minutes, 12.5 minutes, 13 minutes, 13.5 minutes, 14 minutes, 14.5 minutes or 15 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0073] The composite degreasing process is supplemented with ultrasound with a power of 30-35W and a frequency of 28-32kHz. The power of the ultrasound is 30-35W, for example, it can be 30W, 30.5W, 31W, 31.5W, 32W, 32.5W, 33W, 33.5W, 34W, 34.5W or 35W, etc., and the frequency is 28-32kHz, for example, it can be 28kHz, 28.4kHz, 28.8kHz, 29.2kHz, 29.6kHz, 30kHz, 30.4kHz, 30.8kHz, 31.2kHz, 31.6kHz or 32kHz, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0074] The degreasing agent used in the composite degreasing process comprises, by mass percentage: 3-5% polyoxyethylene ether, 0.5-1% aminocarboxylic acid compound, and the remainder is solvent.

[0075] In this invention, the polyoxyethylene ether in the degreasing agent is 3-5% by mass percentage, for example, it can be 3%, 3.2%, 3.4%, 3.6%, 3.8%, 4%, 4.2%, 4.4%, 4.6%, 4.8% or 5%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0076] In this invention, the aminocarboxylic acid compound in the degreasing agent is 0.5-1% by mass, for example, it can be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95% or 1%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0077] The polyoxyethylene ether has a molecular weight of 500-800.

[0078] The aminocarboxylic acid compounds include one or a combination of at least two of the following: EDTA (ethylenediaminetetraacetic acid), EDTA salts, EDDA (ethylenediamine-N,N′-diacetic acid), EDDA salts, IDA (iminodiacetic acid), or IDA salts.

[0079] In this invention, the EDTA salt can be selected from commonly used EDTA salts in the art, such as disodium EDTA, tetrasodium EDTA, and calcium EDTA.

[0080] In this invention, the EDDA salt can be selected from commonly used EDDA salts in the art, such as sodium EDDA and potassium EDDA.

[0081] In this invention, the IDA salt can be selected from commonly used IDA salts in the field, such as sodium IDA and potassium IDA.

[0082] In this invention, the solvent in the degreasing agent can be selected from conventional solvents in the art, such as water or alcohol.

[0083] The temperature for the composite degreasing process is 40-45℃, for example, it can be 40℃, 40.5℃, 41℃, 41.5℃, 42℃, 42.5℃, 43℃, 43.5℃, 44℃, 44.5℃ or 45℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0084] The combined degreasing time is 13-20 min, for example, it can be 13 min, 13.7 min, 14.4 min, 15.1 min, 15.8 min, 16.5 min, 17.2 min, 17.9 min, 18.6 min, 19.3 min or 20 min, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0085] The water washing includes rinsing and spray washing performed sequentially.

[0086] The rinsing process is supplemented with ultrasound with a power of 25-30W and a frequency of 40-45kHz. The power of the ultrasound is 25-30W, for example, it can be 25W, 25.5W, 26W, 26.5W, 27W, 27.5W, 28W, 28.5W, 29W, 29.5W or 30W, etc., and the frequency is 40-45kHz, for example, it can be 40kHz, 40.5kHz, 41kHz, 41.5kHz, 42kHz, 42.5kHz, 43kHz, 43.5kHz, 44kHz, 44.5kHz or 45kHz, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0087] The rinsing temperature is 45-50℃, for example, it can be 45℃, 45.5℃, 46℃, 46.5℃, 47℃, 47.5℃, 48℃, 48.5℃, 49℃, 49.5℃ or 50℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0088] The rinsing time is 6-8 minutes, for example, it can be 6 minutes, 6.2 minutes, 6.4 minutes, 6.6 minutes, 6.8 minutes, 7 minutes, 7.2 minutes, 7.4 minutes, 7.6 minutes, 7.8 minutes or 8 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0089] The temperature of the spray washing is 35-40℃, for example, it can be 35℃, 35.5℃, 36℃, 36.5℃, 37℃, 37.5℃, 38℃, 38.5℃, 39℃, 39.5℃ or 40℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0090] The spray pressure of the spray washing is 0.15-0.2 MPa, for example, it can be 0.15 MPa, 0.155 MPa, 0.16 MPa, 0.165 MPa, 0.17 MPa, 0.175 MPa, 0.18 MPa, 0.185 MPa, 0.19 MPa, 0.195 MPa or 0.2 MPa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0091] The nozzles in the spray washing process rotate at 10-15 r / min, for example, 10 r / min, 10.5 r / min, 11 r / min, 11.5 r / min, 12 r / min, 12.5 r / min, 13 r / min, 13.5 r / min, 14 r / min, 14.5 r / min or 15 r / min, but are not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0092] In this invention, the rotation of the nozzle during spray washing refers to the rotation of the nozzle around the axis or center of the target material.

[0093] The spray washing time is 18-22s, for example, it can be 18s, 18.4s, 18.8s, 19.2s, 19.6s, 20s, 20.4s, 20.8s, 21.2s, 21.6s or 22s, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0094] The alcohol washing process includes: a first-stage alcohol washing, a second-stage alcohol washing, and a third-stage alcohol washing performed sequentially.

[0095] The alcohol solution used in the alcohol washing includes: ethanol solution and / or isopropanol solution.

[0096] The mass concentration of the alcohol solution used in the first-stage alcohol washing is 92-96%, for example, it can be 92%, 92.4%, 92.8%, 93.2%, 93.6%, 94%, 94.4%, 94.8%, 95.2%, 95.6% or 96%, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0097] The temperature of the first-stage alcohol washing is 30-35℃, for example, it can be 30℃, 30.5℃, 31℃, 31.5℃, 32℃, 32.5℃, 33℃, 33.5℃, 34℃, 34.5℃ or 35℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0098] The time for the first-stage alcohol wash is 4-6 minutes, for example, it can be 4 minutes, 4.2 minutes, 4.4 minutes, 4.6 minutes, 4.8 minutes, 5 minutes, 5.2 minutes, 5.4 minutes, 5.6 minutes, 5.8 minutes or 6 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0099] The alcohol solution used in the secondary alcohol washing process has a mass concentration of ≥99.9%.

[0100] The secondary alcohol washing process is supplemented with ultrasound with a power of 15-20W and a frequency of 12-15kHz. The power of the ultrasound is 15-20W, for example, it can be 15W, 15.5W, 16W, 16.5W, 17W, 17.5W, 18W, 18.5W, 19W, 19.5W or 20W, etc., and the frequency is 12-15kHz, for example, it can be 12kHz, 12.3kHz, 12.6kHz, 12.9kHz, 13.2kHz, 13.5kHz, 13.8kHz, 14.1kHz, 14.4kHz, 14.7kHz or 15kHz, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0101] The temperature of the secondary alcohol wash is 30-35℃, for example, it can be 30℃, 30.5℃, 31℃, 31.5℃, 32℃, 32.5℃, 33℃, 33.5℃, 34℃, 34.5℃ or 35℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0102] The humidity during the secondary alcohol washing process is controlled to be ≤30%, for example, it can be 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28% or 30%, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0103] The secondary alcohol wash time is 3-5 min, for example, it can be 3 min, 3.2 min, 3.4 min, 3.6 min, 3.8 min, 4 min, 4.2 min, 4.4 min, 4.6 min, 4.8 min or 5 min, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0104] The three-stage alcohol washing is carried out in an alcohol atmosphere;

[0105] The temperature of the three-stage alcohol washing is 40-45℃, for example, it can be 40℃, 40.5℃, 41℃, 41.5℃, 42℃, 42.5℃, 43℃, 43.5℃, 44℃, 44.5℃ or 45℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0106] The time for the three-stage alcohol wash is 2-3 minutes, for example, it can be 2 minutes, 2.1 minutes, 2.2 minutes, 2.3 minutes, 2.4 minutes, 2.5 minutes, 2.6 minutes, 2.7 minutes, 2.8 minutes, 2.9 minutes or 3 minutes, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0107] After the alcohol washing is completed, the product is dried.

[0108] The drying process includes a first drying and a second drying, performed sequentially.

[0109] The temperature of the first drying step is 45-50℃, for example, it can be 45℃, 45.5℃, 46℃, 46.5℃, 47℃, 47.5℃, 48℃, 48.5℃, 49℃, 49.5℃ or 50℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0110] The wind speed of the drying gas in the first drying process is 1.5-2 m / s, for example, it can be 1.5 m / s, 1.55 m / s, 1.6 m / s, 1.65 m / s, 1.7 m / s, 1.75 m / s, 1.8 m / s, 1.85 m / s, 1.9 m / s, 1.95 m / s or 2 m / s, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0111] Wherein, the humidity of the drying gas in the first drying process is ≤20%, for example, it can be 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11% or 10%, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0112] The first drying time is 3-4 minutes, for example, it can be 3 minutes, 3.1 minutes, 3.2 minutes, 3.3 minutes, 3.4 minutes, 3.5 minutes, 3.6 minutes, 3.7 minutes, 3.8 minutes, 3.9 minutes or 4 minutes, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0113] The second drying temperature is 55-60℃, for example, it can be 55℃, 55.5℃, 56℃, 56.5℃, 57℃, 57.5℃, 58℃, 58.5℃, 59℃, 59.5℃ or 60℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0114] The wind speed of the drying gas in the second drying process is 1.5-2 m / s, for example, it can be 1.5 m / s, 1.55 m / s, 1.6 m / s, 1.65 m / s, 1.7 m / s, 1.75 m / s, 1.8 m / s, 1.85 m / s, 1.9 m / s, 1.95 m / s or 2 m / s, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0115] Wherein, the humidity of the drying gas in the first drying process is ≤20%, for example, it can be 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11% or 10%, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0116] The second drying time is 2-3 minutes, for example, it can be 2 minutes, 2.1 minutes, 2.2 minutes, 2.3 minutes, 2.4 minutes, 2.5 minutes, 2.6 minutes, 2.7 minutes, 2.8 minutes, 2.9 minutes or 3 minutes, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0117] In this invention, a protective gas is used as the drying medium during the drying process, and the humidity is controlled by the water vapor in the gas.

[0118] II. To illustrate the cleaning effect achievable by the target cleaning method provided by this invention, the following practical example is used for explanation:

[0119] Example 1

[0120] This embodiment provides a target cleaning method, the target cleaning method comprising:

[0121] The target material (tungsten target material, purity 99.9%) was subjected to dust removal, composite degreasing, water washing and alcohol washing in sequence to obtain a clean target material;

[0122] The entire cleaning process was carried out in a closed environment with a pressure of 0.1 MPa and a protective gas (nitrogen) introduced at an airflow velocity of 0.8 m / s.

[0123] The dust removal temperature is 27℃, supplemented by ultrasound with a power of 22W and a frequency of 19kHz, for a time of 12min;

[0124] The composite degreasing process is supplemented by ultrasound with a power of 32W and a frequency of 30kHz. The degreasing agent used includes, by mass percentage: 4% polyoxyethylene ether (molecular weight 600), 0.8% aminocarboxylic acid compound (EDTA), and the balance is solvent (water); the composite degreasing temperature is 42℃ and the time is 16min.

[0125] The water washing includes: rinsing and spray washing performed sequentially; the rinsing is supplemented by ultrasound with a power of 27W and a frequency of 42kHz; the rinsing temperature is 47℃ and the time is 7min; the spray washing temperature is 38℃, the spray pressure is 0.18MPa, the nozzle rotates at 12r / min, and the time is 20s.

[0126] The alcohol washing process includes three sequential stages: a primary alcohol wash, a secondary alcohol wash, and a tertiary alcohol wash. The alcohol used in the primary alcohol wash is isopropanol. The primary alcohol wash has a concentration of 94%, a temperature of 32°C, and a duration of 5 minutes. The secondary alcohol wash has a concentration of 99.9%, is performed with 18W of ultrasound at a frequency of 13.5kHz, a temperature of 32°C, a controlled humidity of 30%, and a duration of 4 minutes. The tertiary alcohol wash is conducted in an alcohol atmosphere at a temperature of 42°C for 2.5 minutes.

[0127] After the alcohol washing is completed, drying is performed, including a first drying and a second drying in sequence; the temperature of the first drying is 47°C, the wind speed of the drying gas is 1.8 m / s, the humidity of the drying gas is 20%, and the time is 3.5 min; the temperature of the second drying is 57°C, the wind speed of the drying gas is 1.8 m / s, the humidity of the drying gas is 20%, and the time is 2.5 min.

[0128] Example 2

[0129] This embodiment provides a target cleaning method, the target cleaning method comprising:

[0130] The target material (copper target material, purity 99.9%) was subjected to dust removal, composite degreasing, water washing and alcohol washing in sequence to obtain a clean target material;

[0131] The entire cleaning process was carried out in a closed environment with a pressure of 0.08 MPa and a protective gas (argon) introduced at a gas flow rate of 0.5 m / s.

[0132] The dust removal temperature is 25℃, supplemented by ultrasonic waves with a power of 25W and a frequency of 18kHz for 15 minutes.

[0133] The composite degreasing process is supplemented by ultrasound with a power of 30W and a frequency of 28kHz. The degreasing agent used includes, by mass percentage: 3% polyoxyethylene ether (molecular weight 600), 1% aminocarboxylic acid compound (disodium EDTA), and the balance is solvent (water). The composite degreasing temperature is 40℃ and the time is 20min.

[0134] The water washing includes: rinsing and spray washing performed sequentially; the rinsing is supplemented by ultrasound with a power of 25W and a frequency of 40kHz; the rinsing temperature is 50℃ and the time is 6min; the spray washing temperature is 35℃, the spray pressure is 0.2MPa, the nozzle rotates at 10r / min, and the time is 22s.

[0135] The alcohol washing process includes three sequential stages: a primary alcohol wash, a secondary alcohol wash, and a tertiary alcohol wash. The alcohol used in the alcohol wash includes isopropanol. The primary alcohol wash has a concentration of 92% by mass, a temperature of 30°C, and a duration of 6 minutes. The secondary alcohol wash has a concentration of 99.9% by mass, supplemented by ultrasound at a power of 15W and a frequency of 12kHz, a temperature of 35°C, a controlled humidity of 10%, and a duration of 3 minutes. The tertiary alcohol wash is performed in an alcohol atmosphere at a temperature of 40°C for 3 minutes.

[0136] After the alcohol washing is completed, drying is performed, including a first drying and a second drying in sequence; the temperature of the first drying is 45°C, the wind speed of the drying gas is 1.5m / s, the humidity of the drying gas is 20%, and the time is 4min; the temperature of the second drying is 55°C, the wind speed of the drying gas is 2m / s, the humidity of the drying gas is 20%, and the time is 3min.

[0137] Example 3

[0138] This embodiment provides a target cleaning method, the target cleaning method comprising:

[0139] The target material (tungsten target material, purity 99.9%) was subjected to dust removal, composite degreasing, water washing and alcohol washing in sequence to obtain a clean target material;

[0140] The entire cleaning process was carried out in a closed environment with a pressure of 0.12 MPa and a protective gas (helium) introduced at an airflow speed of 1 m / s.

[0141] The dust removal temperature is 30℃, supplemented by ultrasound with a power of 20W and a frequency of 20kHz, for a time of 10min;

[0142] The composite degreasing process is supplemented by ultrasound with a power of 35W and a frequency of 32kHz. The degreasing agent used includes, by mass percentage: 5% polyoxyethylene ether (molecular weight 600), 0.5% aminocarboxylic acid compound (IDA), and the balance is solvent (water); the composite degreasing temperature is 45℃ and the time is 13min.

[0143] The water washing includes: rinsing and spray washing performed sequentially; the rinsing is supplemented by ultrasound with a power of 30W and a frequency of 45kHz; the rinsing temperature is 45℃ and the time is 8min; the spray washing temperature is 40℃, the spray pressure is 0.15MPa, the nozzle rotates at 15r / min, and the time is 18s.

[0144] The alcohol washing process includes three sequential stages: a primary alcohol wash, a secondary alcohol wash, and a tertiary alcohol wash. The alcohol solution used in the alcohol wash includes ethanol. The primary alcohol wash uses an alcohol solution with a mass concentration of 96%, a temperature of 35°C, and a time of 4 minutes. The secondary alcohol wash uses an alcohol solution with a mass concentration of 99.9%, supplemented by ultrasound at a power of 20W and a frequency of 15kHz, at a temperature of 30°C, with the operating humidity controlled at 20%, for a time of 5 minutes. The tertiary alcohol wash is performed in an alcohol atmosphere at a temperature of 45°C for 2 minutes.

[0145] After the alcohol washing is completed, drying is performed, including a first drying and a second drying in sequence; the temperature of the first drying is 50°C, the wind speed of the drying gas is 2m / s, the humidity of the drying gas is 10%, and the time is 3min; the temperature of the second drying is 60°C, the wind speed of the drying gas is 1.5m / s, the humidity of the drying gas is 10%, and the time is 2min.

[0146] Example 4

[0147] The only difference from Example 1 is that ultrasound is not used in the dust removal process.

[0148] Example 5

[0149] The only difference from Example 1 is that the frequency of the ultrasound in the dust removal is 30 kHz.

[0150] Example 6

[0151] The only difference from Example 1 is that ultrasonication is not performed in the composite degreasing process.

[0152] Example 7

[0153] The only difference from Example 1 is that the ultrasonic frequency in the composite degreasing process is 20 kHz.

[0154] Example 8

[0155] The only difference from Example 1 is that ultrasonication is not performed during rinsing.

[0156] Example 9

[0157] The only difference from Example 1 is that the ultrasonic frequency during rinsing is 30 kHz.

[0158] Example 10

[0159] The only difference from Example 1 is that ultrasound is not performed during rinsing, while the ultrasound for rinsing is performed during spray washing.

[0160] Example 11

[0161] The only difference from Example 1 is that no rinsing is performed.

[0162] Example 12

[0163] The only difference from Example 1 is that spray washing is not performed.

[0164] Example 13

[0165] The only difference from Example 1 is that sonication is not performed during the secondary alcohol wash.

[0166] Example 14

[0167] The only difference from Example 1 is that ultrasound is not performed in the secondary alcohol wash, while the ultrasound of the secondary alcohol wash is performed in the primary alcohol wash.

[0168] Example 15

[0169] The only difference from Example 1 is that ultrasound is not performed in the second-stage alcohol wash, while the ultrasound of the second-stage alcohol wash is performed in the third-stage alcohol wash.

[0170] Example 16

[0171] The only difference from Example 1 is that a first-stage alcohol wash is not performed.

[0172] Example 17

[0173] The only difference from Example 1 is that a secondary alcohol wash is not performed.

[0174] Example 18

[0175] The only difference from Example 1 is that the three-stage alcohol washing is not performed.

[0176] Comparative Example 1

[0177] The only difference from Example 1 is that the degreasing agent does not contain polyoxyethylene ether.

[0178] Comparative Example 2

[0179] The only difference from Example 1 is that the degreasing agent does not contain aminocarboxylic acid compounds, namely EDTA.

[0180] Comparative Example 3

[0181] The only difference from Example 1 is that the polyoxyethylene ether content in the degreasing agent is 2% by mass.

[0182] Comparative Example 4

[0183] The only difference from Example 1 is that the polyoxyethylene ether content in the degreasing agent is 6% by mass.

[0184] Comparative Example 5

[0185] The only difference from Example 1 is that the mass percentage of aminocarboxylic acid compound EDTA in the degreasing agent is 0.1%.

[0186] Comparative Example 6

[0187] The only difference from Example 1 is that the mass percentage of aminocarboxylic acid compound EDTA in the degreasing agent is 2%.

[0188] Comparative Example 7

[0189] The only difference from Example 1 is that the polyoxyethylene ether is replaced with an equal amount of sodium lignosulfonate.

[0190] Comparative Example 8

[0191] The only difference from Example 1 is that the aminocarboxylic acid compound, i.e., EDTA, is replaced with an equal amount of citric acid.

[0192] The surface evaluation indicators of the clean targets obtained in the above embodiments and comparative examples are detailed in Table 1 below. The amount of oil residue was obtained by analysis using a hyperspectral camera, and the amount of microparticles was obtained using an automatic particle counter.

[0193] Table 1

[0194]

[0195] As shown in Table 1, the solution provided by the present invention optimizes the composition of the degreasing agent and effectively removes oil and impurities from the target material by leveraging the synergistic effect of polyoxyethylene ether and aminocarboxylic acid compounds, which is beneficial to achieving efficient cleaning of the target material.

[0196] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0197] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0198] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for cleaning a target material, characterized in that, The target cleaning method includes: The target material is subjected to dust removal, composite degreasing, water washing and alcohol washing in sequence to obtain a clean target material; The degreasing agent used in the composite degreasing process comprises, by mass percentage: 3-5% polyoxyethylene ether, 0.5-1% aminocarboxylic acid compound, and the balance being solvent.

2. The target cleaning method as described in claim 1, characterized in that, The cleaning process of the target material is carried out in a closed environment with a pressure of 0.08-0.12 MPa; Preferably, during the cleaning process of the target material, a protective gas is continuously supplied at an airflow velocity of 0.5-1 m / s; Preferably, the dust removal temperature is 25-30℃; Preferably, the dust removal process is supplemented with ultrasound with a power of 20-25W and a frequency of 18-20kHz; Preferably, the dust removal time is 10-15 minutes.

3. The target cleaning method as described in claim 1 or 2, characterized in that, The aminocarboxylic acid compounds include one or a combination of at least two of the following: EDTA, EDTA salts, EDDA, ​​EDDA salts, IDA, or IDA salts.

4. The target cleaning method according to any one of claims 1-3, characterized in that, The temperature for the composite degreasing process is 40-45℃; Preferably, the combined degreasing time is 13-20 minutes.

5. The target cleaning method according to any one of claims 1-4, characterized in that, The composite degreasing process is supplemented by ultrasound with a power of 30-35W and a frequency of 28-32kHz.

6. The target cleaning method according to any one of claims 1-5, characterized in that, The washing process includes rinsing and spray washing performed sequentially.

7. The target cleaning method as described in claim 6, characterized in that, The rinsing process is supplemented with ultrasound at a power of 25-30W and a frequency of 40-45kHz. Preferably, the rinsing temperature is 45-50℃; Preferably, the rinsing time is 6-8 minutes; Preferably, the temperature of the spray washing is 35-40℃; Preferably, the spray pressure of the spray washing is 0.15-0.2 MPa; Preferably, the nozzles in the spray washing process rotate at 10-15 r / min; Preferably, the spray washing time is 18-22 seconds.

8. The target cleaning method according to any one of claims 1-7, characterized in that, The alcohol washing includes: a first-stage alcohol washing, a second-stage alcohol washing, and a third-stage alcohol washing performed sequentially.

9. The target cleaning method as described in claim 8, characterized in that, The alcohol solution used in the alcohol washing includes: ethanol solution and / or isopropanol solution; Preferably, the mass concentration of the alcohol solution used in the first-stage alcohol washing is 92-96%; Preferably, the temperature of the first-stage alcohol washing is 30-35°C; Preferably, the primary alcohol washing time is 4-6 minutes; Preferably, the mass concentration of the alcohol solution used in the secondary alcohol washing is ≥99.9%; Preferably, the secondary alcohol washing is supplemented with ultrasound with a power of 15-20W and a frequency of 12-15kHz; Preferably, the temperature of the secondary alcohol washing is 30-35°C; Preferably, the operating humidity during the secondary alcohol washing is controlled to be ≤30%; Preferably, the secondary alcohol washing time is 3-5 minutes; Preferably, the three-stage alcohol washing is carried out under an alcohol atmosphere; Preferably, the temperature of the three-stage alcohol washing is 40-45°C; Preferably, the time for the three-stage alcohol washing is 2-3 minutes.

10. The target cleaning method according to any one of claims 1-9, characterized in that, After the alcohol washing is completed, the product is dried. Preferably, the drying process includes a first drying and a second drying performed sequentially; Preferably, the temperature of the first drying step is 45-50°C; Preferably, the wind speed of the drying gas in the first drying process is 1.5-2 m / s; Preferably, the humidity of the drying gas in the first drying process is ≤20%; Preferably, the first drying time is 3-4 minutes; Preferably, the temperature of the second drying process is 55-60°C; Preferably, the wind speed of the drying gas in the second drying process is 1.5-2 m / s; Preferably, the humidity of the drying gas in the first drying process is ≤20%; Preferably, the second drying time is 2-3 minutes.

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