A method for surface treatment of a vacuum aluminum cavity of a semiconductor device

Abstract

The application relates to the technical field of semiconductor manufacturing processing, in particular to a surface treatment method for a vacuum aluminum cavity of a semiconductor device, which comprises the following preparation steps: S1, cleaning the vacuum aluminum cavity by using a cleaning agent; S2, placing the cleaned vacuum aluminum cavity in a strong oxidizing agent solution; S3, spraying abrasive to the surface of the vacuum aluminum cavity for polishing treatment to obtain a rough grinding vacuum aluminum cavity; S4, placing the rough grinding vacuum aluminum cavity in a potassium permanganate mixed solution; S5, spraying abrasive to the surface of the vacuum aluminum cavity for polishing treatment to obtain a fine grinding vacuum aluminum cavity; S6, immersing the fine grinding vacuum aluminum cavity in a silane mixed solution; and S7, nitriding aluminum on the surface of the silanized fine grinding vacuum aluminum cavity by using a chemical vapor deposition method. The application reduces unnecessary procedures, reduces strict requirements on the technical level of operators and the precision of equipment, makes the whole method process more simple, greatly shortens the preparation period, and improves the stability and reliability of the whole surface treatment method.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing and processing technology, and specifically to a method for surface treatment of a vacuum aluminum cavity in semiconductor equipment. Background Technology

[0002] In the field of semiconductor device manufacturing, vacuum aluminum cavities play a crucial role, especially in methods such as chemical vapor deposition (CVD) and etching. Vacuum aluminum cavities primarily provide the necessary vacuum environment for various semiconductor manufacturing methods, effectively isolating materials from external air and preventing oxidation, contamination, and other adverse chemical reactions during processing, thus ensuring the accuracy and stability of the methods. Particularly in etching methods, the vacuum aluminum cavity, as one of the core components of the etching machine, constitutes the plasma reaction chamber. Currently, it is typically machined from a single piece of high-purity aluminum alloy without weld seams to ensure low leakage rates, laying the foundation for the etching method and ensuring plasma stability and method accuracy.

[0003] However, existing technologies for fabricating vacuum aluminum cavities have several shortcomings. The fabrication process is extremely cumbersome and complex, involving a series of steps including solvent cleaning to remove oil and dust, acid pickling to remove the oxide layer, alkaline washing to remove organic residues, mechanical polishing, chemical polishing, sandblasting, anodizing to form a protective film, and coating and curing a wear-resistant coating. The entire process demands extremely high levels of operator skill and equipment precision, and requires strict control of the parameters at each step. This not only results in a lengthy fabrication cycle but also significantly reduces production efficiency. Furthermore, despite these numerous steps, existing technologies still struggle to achieve the desired surface smoothness. Etching methods demand extremely high surface smoothness from vacuum aluminum cavities, but existing methods, due to the complexity and difficulty in precise control during surface treatment, often result in unsatisfactory final smoothness, failing to meet the stringent requirements of etching methods for high smoothness. Summary of the Invention

[0004] To address the problems of complexity, time consumption, and poor smoothness in existing methods, this application provides a surface treatment method for vacuum aluminum cavities in semiconductor devices.

[0005] In a first aspect, this application provides a surface treatment method for a vacuum aluminum cavity in a semiconductor device, employing the following technical solution:

[0006] A method for surface treatment of a vacuum aluminum cavity in a semiconductor device includes the following preparation steps:

[0007] S1. Clean the vacuum aluminum cavity with a cleaning agent and let it dry to obtain the cleaned vacuum aluminum cavity.

[0008] S2. Place the cleaned vacuum aluminum cavity in a strong oxidizing agent solution and soak it for a period of time. The strong oxidizing agent solution is composed of sodium thiosulfate 15-20 g / L, magnesium sulfate 15-20 g / L, thiourea 0.5-2 g / L, sodium hypophosphite 10-20 g / L and sodium phosphate 4-9 g / L.

[0009] S3. Select micron-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain a coarsely ground vacuum aluminum cavity.

[0010] S4. Place the coarsely ground vacuum aluminum cavity in a potassium permanganate mixed solution and soak it for a period of time. The potassium permanganate mixed solution is composed of 10-15 g / L potassium permanganate, 2-5 g / L zinc sulfate, 3-5 g / L sodium hydroxide, 2-6 g / L aluminum chloride and 0.5-1.5 g / L sodium dodecyl sulfate.

[0011] S5. Select nano-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain finely ground vacuum aluminum cavity.

[0012] S6. Immerse the finely ground vacuum aluminum cavity in a silane mixture, remove it, and obtain a silanized finely ground vacuum aluminum cavity;

[0013] S7. Using chemical vapor deposition, the silanized finely ground vacuum aluminum cavity is placed in the CVD reaction chamber, the vacuum degree is adjusted to 100-500Pa, TMA and NH3 are introduced, the deposition temperature is set to 800-1000℃, an aluminum nitride coating is deposited on its surface, and then the coating is annealed to obtain the semiconductor equipment vacuum aluminum cavity.

[0014] Preferably, the flow rate of TMA is 10-50 sccm, the flow rate of NH3 is 100-500 sccm, and the coating time is 0.5-2h.

[0015] Preferably, the annealing temperature is 500-600℃, carried out in a nitrogen or argon atmosphere, and the annealing time is 1-2 hours.

[0016] By adopting the above technical solution, this application simplifies the method to steps such as cleaning, soaking in a strong oxidant solution, coarse grinding, soaking in a potassium permanganate mixed solution, fine grinding, silanization, and chemical vapor deposition. This reduces unnecessary procedures, lowers the stringent requirements on the technical level of operators and the precision of equipment, makes the entire process simpler and more efficient, significantly shortens the preparation cycle, and effectively improves production efficiency.

[0017] This technical solution optimizes and precisely controls the parameters of each step, reducing quality fluctuations and defects caused by the complexity of the method and the difficulty in controlling the parameters. It improves the stability and reliability of the entire surface treatment method and ensures the quality consistency of the vacuum aluminum cavity of the semiconductor equipment.

[0018] Meanwhile, by employing micron-level and nano-level abrasives for coarse and fine grinding respectively, the surface roughness of the aluminum cavity can be more precisely controlled, resulting in a smoother and flatter surface. Furthermore, subsequent silanization treatment and chemical vapor deposition coating further optimize the surface quality, ultimately achieving a surface smoothness that meets the stringent requirements of etching methods for high smoothness. This effectively avoids problems such as uneven etching and insufficient precision caused by surface roughness.

[0019] Furthermore, through treatment steps such as immersion in a mixed solution of strong oxidizing agents and potassium permanganate, followed by silanization and chemical vapor deposition to form an aluminum nitride coating, and then annealing, a more uniform, dense, and stable protective film and coating can be formed on the surface of the vacuum aluminum cavity. This not only helps improve the corrosion resistance and wear resistance of the vacuum aluminum cavity, but also effectively isolates it from external air, further reducing the leakage rate in semiconductor manufacturing methods, ensuring plasma stability and method precision, and providing a more reliable and stable vacuum environment for semiconductor device manufacturing, thereby improving the production yield and quality stability of semiconductor devices.

[0020] Preferably, in step S3, the grinding disc rotation speed is set to 800-1200 rpm, and the grinding pressure is 40-80 kPa.

[0021] Preferably, in step S5, the grinding disc rotation speed is set to 1500-2000 rpm, and the grinding pressure is 60-90 kPa.

[0022] Preferably, the nanoscale abrasive is obtained by mixing nanoscale abrasive with an average particle size of 5-10 nm and nanoscale abrasive with an average particle size of 50-200 nm in a weight ratio of (6-9):4.

[0023] Preferably, the micron-sized abrasive is obtained by mixing meter-sized abrasive with an average particle size of 0.1-1μm and micron-sized abrasive with an average particle size of 1-2μm in a weight ratio of (5-8):1.5.

[0024] Preferably, the ratio of the micron-sized abrasive to the solvent is 10-20 g / L.

[0025] Preferably, the ratio of the nano-abrasive to the solvent is 20-30 g / L.

[0026] Preferably, the grinding time in step S3 is 2-3 hours.

[0027] Preferably, the grinding time in step S5 is 2-3 hours.

[0028] By adopting the above technical solutions and optimizing parameter settings, the grinding process becomes more efficient and precise. It can more evenly remove impurities and scratches from the aluminum cavity surface, improving surface smoothness and providing a higher-quality substrate for subsequent surface treatment steps. This reduces processing unevenness caused by differences in surface roughness, enhancing the overall consistency and stability of the method. In the micron-level abrasive grinding stage, reasonable rotation speed and pressure allow the micron-level abrasive to function better, quickly removing larger scratches and rough areas, creating favorable conditions for subsequent nano-level abrasive fine grinding. Optimized parameters in the nano-level abrasive grinding stage help achieve finer surface treatment, further improving surface finish and enabling the aluminum cavity surface to meet higher precision requirements. This satisfies the stringent standards for high smoothness in etching methods, thereby improving plasma stability and the accuracy of the etching method.

[0029] By combining abrasive particles of different sizes in a reasonable way, they can work synergistically during the grinding process. Larger abrasive particles can quickly remove larger defects and protrusions on the surface, while smaller abrasive particles can perform more detailed grinding and polishing, filling in tiny depressions and gaps. By precisely controlling the proportion of abrasive particles of different sizes, a more uniform and efficient surface grinding effect can be achieved, making the aluminum cavity surface smoother in microstructure, reducing micro-defects, and improving surface quality.

[0030] The surface treatment method, after the aforementioned parameter optimization, achieves more precise control and improvement at each stage from coarse grinding to fine grinding. The resulting vacuum aluminum cavity surface not only possesses higher smoothness but also a more uniform microstructure, better corrosion and wear resistance, and excellent compatibility with subsequent silanization and chemical vapor deposition methods. These comprehensive performance improvements enhance the application of vacuum aluminum cavities in semiconductor manufacturing processes, ensuring stable operation during complex processes such as etching and extending equipment lifespan.

[0031] Chemical vapor deposition (CVD) to deposit an aluminum nitride coating on a surface, followed by annealing, yields an aluminum nitride coating with excellent wear resistance and corrosion resistance. Aluminum nitride possesses high hardness and good chemical stability, effectively resisting corrosion from chemicals generated during etching and other processes, extending the service life of the vacuum aluminum cavity, and reducing equipment maintenance and replacement costs.

[0032] Preferably, the cleaning agent is obtained by mixing petroleum ether, limonene, triethanolamine, dichloromethane, acetone and ethanol in a weight ratio of (2-5):(3-6):(1-2):(5-7):(3-5):15.

[0033] By employing the above technical solutions, stains can be removed efficiently. Petroleum ether effectively dissolves mineral oil stains, while limonene breaks down organic oil stains and also has a certain deodorizing function; the combined effect of these two broadens the range of oil stain dissolution. Dichloromethane, acetone, and ethanol are all highly polar solvents that can quickly penetrate and dissolve various organic pollutants, exhibiting excellent removal capabilities for oil stains, dust, and other impurities, and can comprehensively remove oil stains, dust, and organic residues from the surface of the vacuum aluminum cavity. Triethanolamine, as a surfactant, reduces the adhesion between oil stains and the aluminum cavity surface, emulsifies and disperses the oil stains in the cleaning agent, preventing re-adhesion, and synergistically enhances the overall cleaning efficiency with petroleum ether and limonene. Dichloromethane, acetone, and ethanol have low boiling points and are easily volatile, allowing the cleaned aluminum cavity to dry quickly, reducing the waiting time for subsequent methods and improving production efficiency.

[0034] Preferably, the solvent is composed of aliphatic hydrocarbons, aromatic hydrocarbons, phosphoric acid, sulfuric acid, polyols, anionic surfactants and water in a weight ratio of (4-6):(2-3):(0.5-1):(0.2-0.8):(2-4):(1-2):15.

[0035] By adopting the above technical solution and optimizing the solvent composition, its combined use with abrasives not only removes physical impurities from the surface but also improves the microstructure of the aluminum cavity surface through a synergistic effect of chemical and mechanical processes. This makes subsequent processing steps such as coating easier and improves the overall quality of the surface treatment method.

[0036] Phosphoric acid and sulfuric acid in the solvent remove oxide layers and inorganic residues. Combined with the mechanical action of the abrasive, they more effectively remove oxide scale and microparticles from the aluminum surface, resulting in a smoother and more even surface. Polyols and anionic surfactants in the solvent reduce surface tension, allowing the solvent and abrasive to spread better on the aluminum cavity surface. This increases the contact area and adhesion between the abrasive and the surface, enabling the abrasive to be more evenly distributed across the entire surface during blasting, avoiding localized over- or under-wearing. Aliphatic and aromatic hydrocarbons, as the main components of the solvent, can better penetrate into the tiny crevices of the surface, dissolving stubborn oil stains. During blasting, the abrasive physically removes these dissolved impurities and tiny surface protrusions, achieving a more refined cleaning effect.

[0037] Under the jetting action of solvent and abrasive, micron- and nano-sized abrasives can penetrate deeper into the tiny pores and defects on the surface, further optimizing the surface microstructure and making the surface more delicate and uniform, creating more ideal conditions for subsequent processes such as oxidation, silanization and chemical vapor deposition.

[0038] Preferably, the silane mixture is obtained by uniformly mixing vinyltrimethoxysilane coupling agent, γ-aminopropyltriethoxysilane, γ-methacryloyloxypropyltriethoxysilane and organic solvent in a weight ratio of (0.5-1):(2-3):(3-6):20.

[0039] Preferably, the silanization treatment is performed at a temperature of 40-45°C for 2-3 hours.

[0040] By adopting the above technical solution, the surface energy and wettability of the silane mixture after treatment are optimized, so that the surface is more uniformly covered by the subsequent chemical vapor deposition precursor, which is conducive to the uniform growth of aluminum nitride coating, improves the density and uniformity of the coating, and further enhances the surface performance.

[0041] Vinyltrimethoxysilane coupling agents and other components react chemically with the aluminum surface to form strong chemical bonds. These bonds also allow for good adhesion to the subsequent aluminum nitride coating, significantly improving the adhesion between the coating and the aluminum cavity surface, reducing the risk of coating peeling, and extending the cavity's service life. γ-aminopropyltriethoxysilane and γ-methacryloyloxypropyltriethoxysilane, through the chemical reactions of their amino and methacryloyloxy groups with the aluminum surface, respectively, form strong chemical bonds, resulting in a more secure adhesion of the coating to the aluminum cavity surface. The three silane coupling agents work synergistically to form a uniform and dense silane film on the aluminum cavity surface, effectively isolating the aluminum surface from external environmental corrosion, such as preventing oxidation and corrosion, and improving the chemical stability of the aluminum cavity surface.

[0042] In summary, this application has the following beneficial effects:

[0043] 1. The surface treatment method for vacuum aluminum cavities in semiconductor equipment disclosed in this application effectively improves production efficiency and surface treatment quality by simplifying processes and optimizing method parameters. The method steps include cleaning, immersion in a strong oxidizing agent solution, rough grinding, immersion in a potassium permanganate mixed solution, fine grinding, silanization, and chemical vapor deposition. Compared with traditional complex methods, it reduces unnecessary steps, lowers the requirements for operators and technical equipment, makes the process more concise and efficient, significantly shortens the preparation cycle, and improves production efficiency. The staged treatment with micron- and nano-sized abrasives allows for more precise control of surface roughness, resulting in a smoother and flatter surface that meets the high smoothness requirements of etching methods, avoiding problems such as uneven etching and insufficient precision. The treatment with the strong oxidizing agent solution and potassium permanganate mixed solution, along with subsequent silanization and chemical vapor deposition coatings, forms a more uniform and dense protective film and coating, enhancing the corrosion resistance and wear resistance of the aluminum cavity, effectively isolating it from external air, and significantly reducing leakage rate. Detailed Implementation

[0044] Example

[0045] Example 1

[0046] A method for surface treatment of a vacuum aluminum cavity in a semiconductor device includes the following preparation steps:

[0047] S1. Clean the vacuum aluminum cavity with a cleaning agent and let it dry to obtain the cleaned vacuum aluminum cavity.

[0048] S2. Place the cleaned vacuum aluminum cavity in a strong oxidizing agent solution and soak for 1 hour. The strong oxidizing agent solution is composed of sodium thiosulfate 15 g / L, magnesium sulfate 20 g / L, thiourea 0.5 g / L, sodium hypophosphite 10 g / L and sodium phosphate g / L.

[0049] S3. Select micron-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain a coarsely ground vacuum aluminum cavity.

[0050] Micron-sized abrasives are obtained by mixing meter-sized abrasives with an average particle size of 0.1 μm and micron-sized abrasives with an average particle size of 1 μm at a weight ratio of 5:1.5.

[0051] The ratio of micron-sized abrasive to solvent is 10 g / L;

[0052] The grinding time in step S3 is 2 hours;

[0053] The grinding disc speed is set to 800 rpm, and the grinding pressure is 40 kPa;

[0054] The solvent is composed of aliphatic hydrocarbons (n-hexane), aromatic hydrocarbons (toluene), phosphoric acid, sulfuric acid, polyol (butanediol), anionic surfactant (sodium N-oleoyl-N-methyltaurate), and water in a weight ratio of 4:2:0.5:0.2:2:1:15.

[0055] S4. Place the coarsely ground vacuum aluminum cavity in a potassium permanganate mixed solution and soak it for a period of time. The potassium permanganate mixed solution is composed of 10-15 g / L potassium permanganate, 2-5 g / L zinc sulfate, 3-5 g / L sodium hydroxide, 2-6 g / L aluminum chloride and 0.5-1.5 g / L sodium dodecyl sulfate.

[0056] S5. Select nano-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain finely ground vacuum aluminum cavity.

[0057] The nano-sized abrasive is obtained by mixing nano-sized abrasive with an average particle size of 5 nm and nano-sized abrasive with an average particle size of 50 nm in a weight ratio of 6:4.

[0058] The ratio of nano-sized abrasive to solvent is 20 g / L;

[0059] The grinding time is 2 hours;

[0060] The grinding disc speed is set to 1500 rpm, and the grinding pressure is 60 kPa;

[0061] The solvent is composed of aliphatic hydrocarbons (n-hexane), aromatic hydrocarbons (toluene), phosphoric acid, sulfuric acid, polyol (butanediol), anionic surfactant (sodium N-oleoyl-N-methyltaurate), and water in a weight ratio of 4:2:0.5:0.2:2:1:15.

[0062] S6. Immerse the finely ground vacuum aluminum cavity in a silane mixture, remove it, and obtain a silanized finely ground vacuum aluminum cavity;

[0063] The silane mixture is obtained by uniformly mixing vinyltrimethoxysilane coupling agent, γ-aminopropyltriethoxysilane, γ-methacryloyloxypropyltriethoxysilane and organic solvent (toluene) in a weight ratio of 0.5:2:3:20.

[0064] The silanization treatment was carried out at a temperature of 40℃ for 2 hours.

[0065] S7. Using chemical vapor deposition, the silanized finely ground vacuum aluminum cavity is placed in the CVD reaction chamber, the vacuum degree is adjusted to 100Pa, and then TMA and NH3 are introduced. The deposition temperature is set at 800℃, and an aluminum nitride coating is deposited on its surface. Then the coating is annealed to obtain the semiconductor equipment vacuum aluminum cavity.

[0066] The flow rate of TMA was 10 sccm, the flow rate of NH3 was 100 sccm, and the coating time was 0.5 h.

[0067] The annealing temperature was 500℃, and the annealing was carried out in a nitrogen atmosphere for 1 hour.

[0068] The difference between Examples 2-3 and Example 1 lies in the type, amount, and parameters of the raw materials used for the surface treatment of the vacuum aluminum cavity in the semiconductor equipment. The specific differences are shown in Table 1.

[0069] Table 1. Raw material types, dosages, and parameters for surface treatment of vacuum aluminum cavities in semiconductor equipment.

[0070]

[0071]

[0072] Example

[0073] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this embodiment and embodiment 1 is that the micron-level abrasive is a meter-level abrasive with an average particle size of 0.1μm.

[0074] Example 5

[0075] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this embodiment and embodiment 1 is that the nano-abrasive is made of nano-abrasive with an average particle size of 5nm.

[0076] Example 6

[0077] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this embodiment and embodiment 1 is that the alkane mixture is obtained by uniformly mixing γ-aminopropyltriethoxysilane, γ-methacryloyloxypropyltriethoxysilane and organic solvent (butanediol) in a weight ratio of 2:3:20.

[0078] Example 7

[0079] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this embodiment and embodiment 1 is that aliphatic hydrocarbons are omitted in the solvent.

[0080] Example 8

[0081] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this embodiment and embodiment 1 is that aromatic hydrocarbons are omitted in the solvent.

[0082] Comparative Example

[0083] Comparative Example 1

[0084] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this comparative example and Example 1 is that the strong oxidant solution is replaced with pure water.

[0085] Comparative Example 2

[0086] A method for surface treatment of vacuum aluminum cavity of semiconductor equipment. The difference between this comparative example and Example 1 is that the potassium permanganate mixed solution is replaced with pure water.

[0087] Comparative Example 3

[0088] A method for surface treatment of vacuum aluminum cavity of semiconductor device. The difference between this comparative example and Example 1 is that the silane mixture is replaced with pure water.

[0089] Comparative Example 4

[0090] A method for surface treatment of vacuum aluminum cavity of semiconductor equipment. The difference between this comparative example and Example 1 is that the strong oxidant solution is composed of 15-20 g / L nitric acid, 15-20 g / L magnesium sulfate, 0.5-2 g / L thiourea, 10-20 g / L sodium hypophosphite and 4-9 g / L sodium phosphate.

[0091] Detection methods / test methods

[0092] Surface smoothness detection: The surface roughness of the vacuum aluminum cavity of the semiconductor device was measured using an atomic force microscope (AFM). The measurement area was 1μm×1μm, and the measurement positions were selected in typical processing areas on the cavity surface. Three different positions were measured for each sample, and the average value was taken as the final result.

[0093] Leakage detection: A helium mass spectrometer leak detector was used to detect the leak rate of the vacuum aluminum cavity in the semiconductor equipment. Before detection, the cavity was evacuated to a background vacuum level of 5 × 10⁻⁶. −5 Pa, then helium gas is introduced into the cavity at a pressure of 1 × 10⁻⁶. 4 Maintain the pressure at 100 Pa for 30 minutes to allow helium to fully permeate the cavity. Next, connect the cavity to the helium mass spectrometer leak detector, start the instrument to perform the test, and record the leak rate value.

[0094] Coating adhesion test: A scratch tester was used to create scratches of a certain length and spacing on the coating surface. The scratches were 10 mm long and 1 mm apart. During the scratching process, the load was gradually increased, starting from 1 N and increasing by 0.5 N each time, until the load reached 5 N. The peeling of the coating at the scratches was observed under a high-powered microscope.

[0095] Corrosion resistance test: The vacuum aluminum chamber of the semiconductor equipment was placed in a salt spray test chamber and sprayed with a 5% salt solution at 35°C for 48 hours. The surface corrosion was then observed. The experimental data are shown in Table 2.

[0096] Table 2. Experimental data of Examples 1-8 and Comparative Examples 1-4

[0097]

[0098] Experimental data from Examples 1-8 show that the surface treatment method for the vacuum aluminum cavity of the semiconductor device can significantly improve surface smoothness, reduce leakage rate, enhance coating adhesion and corrosion resistance, and meet the high requirements of etching methods for the vacuum aluminum cavity.

[0099] The surface roughness Ra values ​​of Examples 1-8 are all below 5.5 nm, with the Ra values ​​of Examples 1-3 reaching 3.5-4.1 nm, which is much lower than the 18.7-25.3 nm of Comparative Examples 1-4. This indicates that the method can significantly improve surface smoothness and meet the high smoothness requirements of etching methods.

[0100] The leakage rates of Examples 1-8 were all below 6.2 × 10⁻⁸. -10 Pa.m 3 / s, far below the specified standard value of 1×10 -8 Pa.m 3 / s and 1.2×10 in Comparative Examples 1-4 -7 Pa.m 3 / s indicates that the treatment steps, including strong oxidant solution, potassium permanganate mixed solution, and subsequent silanization and coating treatment, effectively enhance the density and integrity of the aluminum cavity surface, isolate external air, reduce leakage rate, and ensure the stability of plasma and the accuracy of the etching method.

[0101] The coatings in Examples 1-8 all showed good adhesion in the scratch test, and no peeling occurred when the load reached 5N. No coating peeling was also found in the tape peeling test, indicating that the silanization treatment and chemical vapor deposition method optimized the coating adhesion, reduced the risk of coating peeling, and extended the service life of the cavity.

[0102] In the salt spray test, the samples of Examples 1-8 showed no obvious corrosion, while the samples of Comparative Examples 1-4 showed varying degrees of corrosion, indicating that the method effectively improved the corrosion resistance of the aluminum cavity.

[0103] In Comparative Example 1, after using pure water instead of a strong oxidizing agent solution, the surface roughness Ra value increased to 18.7 nm, and the leakage rate was 1.5 × 10⁻⁻⁻⁶. 7 The coating adhesion decreased significantly at Pa·m³ / s (peeling occurred under a load of 3N), and the corrosion resistance also deteriorated, indicating that the strong oxidant solution played an important role in improving surface smoothness, reducing leakage rate, and enhancing coating adhesion and corrosion resistance.

[0104] In Comparative Example 2, replacing the potassium permanganate mixed solution with purified water increased both the surface roughness Ra value and the leakage rate, by 15.3 nm and 2.0 × 10⁻⁶ nm, respectively. -8 Pa.m 3 / s, the coating adhesion also decreased (peeling off under a load of 4N), and a small number of corrosion spots appeared, indicating that the potassium permanganate mixed solution has a positive effect on the surface treatment effect.

[0105] Comparative Example 3: After the silane mixture was replaced with pure water, the surface roughness Ra value was 16.2 nm, and the leakage rate was 10. -7 Pa.m 3 / s, the coating adhesion decreased (peeling at a load of 3.5N), and multiple corrosions appeared, indicating that silanization treatment is crucial for improving surface properties and coating quality.

[0106] In Comparative Example 4, after changing the composition of the strong oxidant solution, the surface roughness Ra value and leakage rate were 14.9 nm and 1.8 × 10¹⁰, respectively. -8 Pa.m 3 / s, the coating adhesion and corrosion resistance also decreased, indicating that the original strong oxidant solution composition was more effective in obtaining good surface treatment results.

[0107] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for surface treatment of a vacuum aluminum cavity in a semiconductor device, characterized in that, The preparation steps include the following: S1. Clean the vacuum aluminum cavity with a cleaning agent and let it dry to obtain the cleaned vacuum aluminum cavity. S2. Place the cleaned vacuum aluminum cavity in a strong oxidizing agent solution and soak it for a period of time. The strong oxidizing agent solution is composed of sodium thiosulfate 15-20 g / L, magnesium sulfate 15-20 g / L, thiourea 0.5-2 g / L, sodium hypophosphite 10-20 g / L and sodium phosphate 4-9 g / L. S3. Select micron-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain a coarsely ground vacuum aluminum cavity. S4. Place the coarsely ground vacuum aluminum cavity in a potassium permanganate mixed solution and soak it for a period of time. The potassium permanganate mixed solution is composed of 10-15 g / L potassium permanganate, 2-5 g / L zinc sulfate, 3-5 g / L sodium hydroxide, 2-6 g / L aluminum chloride and 0.5-1.5 g / L sodium dodecyl sulfate. S5. Select nano-sized abrasive and solvent to mix to obtain abrasive, then spray the abrasive evenly onto the clean surface of the vacuum aluminum cavity for polishing, rinse, and obtain finely ground vacuum aluminum cavity. S6. Immerse the finely ground vacuum aluminum cavity in a silane mixture, remove it, and obtain a silanized finely ground vacuum aluminum cavity; S7. Using chemical vapor deposition, the silanized finely ground vacuum aluminum cavity is placed in the CVD reaction chamber, the vacuum degree is adjusted to 100-500Pa, TMA and NH3 are introduced, the deposition temperature is set at 800-1000℃, an aluminum nitride coating is deposited on its surface, and then the coating is annealed to obtain the semiconductor equipment vacuum aluminum cavity. The silane mixture is obtained by uniformly mixing vinyltrimethoxysilane coupling agent, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltriethoxysilane and organic solvent in a weight ratio of (0.5-1):(2-3):(3-6):

20.

2. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: In S3, the grinding disc rotation speed is set to 800-1200 rpm, and the grinding pressure is 40-80 kPa.

3. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: In S5, the grinding disc rotation speed is set to 1500-2000 rpm, and the grinding pressure is 60-90 kPa.

4. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: The cleaning agent is prepared by mixing petroleum ether, limonene, triethanolamine, dichloromethane, acetone and ethanol in a weight ratio of (2-5):(3-6):(1-2):(5-7):(3-5):

15.

5. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: The silanization process is carried out at a temperature of 40-45°C for 2-3 hours.

6. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 4, characterized in that: The nanoscale abrasive is obtained by mixing nanoscale abrasive with an average particle size of 5-10 nm and nanoscale abrasive with an average particle size of 50-200 nm in a weight ratio of (6-9):

4.

7. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: The micron-sized abrasive is obtained by mixing meter-sized abrasive with an average particle size of 0.1-1μm and micron-sized abrasive with an average particle size of 1-2μm in a weight ratio of (5-8):1.

5.

8. The surface treatment method for a vacuum aluminum cavity in a semiconductor device according to claim 1, characterized in that: The solvent is composed of aliphatic hydrocarbons, aromatic hydrocarbons, phosphoric acid, sulfuric acid, polyols, anionic surfactants and water in a weight ratio of (4-6):(2-3):(0.5-1):(0.2-0.8):(2-4):(1-2):15.

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