Quartz crucible cleaning method

Abstract

The invention discloses a quartz crucible cleaning method which specifically comprises the following steps: S1, pretreatment: (1) mechanical scrubbing: placing a quartz crucible to be cleaned in special scrubbing equipment, and using a soft nylon brush or a sponge brush; the invention relates to the technical field of quartz crucible production. According to the quartz crucible cleaning method, various cleaning technologies such as mechanical scrubbing, high-pressure water gun flushing, plasma cleaning, acid pickling and pure water ultrasonic cleaning are comprehensively applied, and various pollutants including metal ions, organic matter and particle impurities on the surface of the quartz crucible can be comprehensively and efficiently removed; the surface cleanliness of the cleaned crucible meets the high-standard requirement of the semiconductor and photovoltaic industry, various cleaning parameters such as the concentration, temperature and pickling time of a pickling solution and the power and time of plasma cleaning are reasonably controlled in the cleaning process, and the cleaning quality is improved. And corrosion and damage to the crucible body caused by high-concentration strong acid and long-time strong plasma bombardment are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of quartz crucible production, in particular to a quartz crucible cleaning method. Background Art

[0002] Quartz crucibles are made of high-purity quartz glass and have excellent high-temperature resistance and chemical stability. Quartz crucibles can usually withstand temperatures of hundreds to thousands of degrees Celsius and are not easily corroded by most acids and alkalis. Therefore, they are widely used in melting samples, high-temperature reactions, chemical analysis and other fields. In key processes such as semiconductor single crystal silicon pulling and photovoltaic industry single crystal silicon rod growth, quartz crucibles serve as core containers, and their surface cleanliness is directly related to the quality and performance of the final product. However, during the production, transportation, storage and use of quartz crucibles, their surfaces will inevitably be contaminated with various pollutants, including but not limited to metal ions (such as iron, aluminum, copper, etc.), organic matter (such as grease, resin, etc.), particulate impurities (such as quartz dust, dust, etc.) and residual chemicals during the processing process.

[0003] At present, the traditional quartz crucible cleaning method has the following main problems: 1. Limited cleaning effect: A single cleaning method is often unable to completely remove different types of contaminants. For example, conventional pickling processes have a certain removal effect on metal ions, but are less effective in removing organic matter and particulate impurities. Ultrasonic cleaning, while able to remove some particulate impurities, is less effective in removing metal ions and organic matter. 2. Severe damage to the crucible body: In order to achieve better cleaning effects, some cleaning methods use high-concentration strong acid or strong alkali solutions. These solutions will corrode the surface structure of the quartz crucible, reduce the strength and service life of the crucible, and affect its stability in high-temperature environments; 3. Prominent environmental issues: Traditional cleaning methods usually use a large amount of chemical reagents, generating a large amount of waste liquid and waste gas, causing serious environmental pollution. At the same time, the treatment cost of these waste liquids and waste gas is high, increasing the production cost of the enterprise; 4. Low degree of automation: Most existing cleaning processes rely on manual operation, which is not only labor-intensive and inefficient, but also prone to unstable cleaning quality due to human factors, introducing secondary pollution. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a quartz crucible cleaning method, which solves the problems mentioned in the above background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A quartz crucible cleaning method specifically comprises the following steps: S1. Preprocessing: (1) Mechanical scrubbing: Place the quartz crucible to be cleaned in a dedicated scrubbing device, use a soft nylon brush or sponge brush, and an appropriate amount of deionized water to perform a preliminary scrubbing of the outer and inner surfaces of the crucible. During the scrubbing process, the rotation speed of the brush is controlled at 50-200 r / min, and the scrubbing time is 2-10 min. (2) High-pressure water gun flushing: After brushing, use a high-pressure water gun to fully flush the crucible. The water pressure of the high-pressure water gun is set to 5-20 MPa, and the flushing time is 1-5 minutes; S2. Plasma cleaning: (1) Equipment preparation: Place the pretreated quartz crucible into a plasma cleaning device equipped with a vacuum chamber, a radio frequency power supply, a gas supply system, and a plasma generator; (2) Vacuuming: Close the door of the vacuum chamber, start the vacuum pump, and reduce the vacuum degree in the chamber to 1-100 Pa to remove air and other impurity gases in the chamber and create a good environment for the generation of plasma; (3) Gas introduction: The working gas is introduced into the vacuum chamber. The working gas is a mixture of oxygen and argon, wherein the volume fraction of oxygen is 10%-50%, and the volume fraction of argon is 50%-90%. The total flow rate of the gas is controlled at 10-100 sccm; (4) Plasma generation and cleaning: Turn on the RF power supply and adjust the RF power to 100-1000W. At the same time, the physical bombardment of the plasma can remove some particulate impurities and metal ions on the surface of the crucible. The cleaning time is 5-30 minutes. S3, pickling: (1) Acid solution preparation: prepare pickling solution, which is composed of hydrofluoric acid, hydrochloric acid and nitric acid, wherein the concentration of hydrofluoric acid is 1%-10%, the concentration of hydrochloric acid is 1%-5%, the concentration of nitric acid is 1%-5%, and the rest is deionized water; (2) Pickling process: immerse the quartz crucible after plasma cleaning in the pickling solution, control the pickling temperature at 20-60 ° C, and the pickling time is 5-30 minutes; (3) Post-pickling treatment: After pickling, remove the crucible from the pickling solution and immediately rinse it with plenty of deionized water to remove the residual acid. The rinsing time should be no less than 5 minutes to ensure that the acid on the surface of the crucible is completely rinsed. S4, pure water ultrasonic cleaning: (1) Equipment preparation: Place the cleaned quartz crucible after pickling into a pure water ultrasonic cleaning device equipped with an ultrasonic generator, a cleaning tank, and a pure water circulation system; (2) Ultrasonic cleaning: inject ultrapure water with a conductivity of ≤0.1μS / cm into the cleaning tank, immerse the crucible completely in the water, turn on the ultrasonic generator, set the ultrasonic frequency to 20-100kHz, the ultrasonic power to 100-1000W, and the cleaning time to 10-60min; (3) Pure water circulation and replacement: During the ultrasonic cleaning process, start the pure water circulation system to keep the water in the cleaning tank flowing and take away the pollutants cleaned in time. At the same time, replace the pure water every 10-30 minutes to ensure the cleaning effect; S5. Drying: (1) Equipment preparation: Place the quartz crucible after ultrasonic cleaning with pure water into the drying equipment, which uses a combination of hot air circulation and infrared heating and is equipped with a heating element, a fan and a temperature control system; (2) Drying process: Start the heating element and the fan, and gradually increase the temperature in the drying equipment to 80-150℃. The hot air circulates in the equipment under the action of the fan, so that the moisture on the surface of the crucible evaporates quickly. At the same time, the infrared heating can penetrate deep into the crucible and accelerate the volatilization of moisture. The drying time is 30-120 minutes, and the specific time is adjusted according to the size and moisture content of the crucible. (3) Cooling: After drying is completed, turn off the heating element and fan, allow the crucible to cool naturally to room temperature in the equipment, and then take out the crucible.

[0006] Preferably, the mechanical scrubbing in S1 is to remove larger granular impurities and some loose pollutants attached to the surface of the crucible.

[0007] Preferably, the flushing angle of the high-pressure water gun in S1 can be adjusted according to the shape of the crucible to ensure that the water flow can cover all parts of the crucible and further flush away residual particulate impurities and dirt generated by brushing.

[0008] Preferably, in S2, plasma generation and cleaning cause the working gas to be ionized under the action of the radio frequency electric field to generate plasma, and the active particles in the plasma chemically react with the organic matter on the surface of the crucible, decomposing it into small molecules such as carbon dioxide and water, and discharge them from the chamber through a vacuum pump.

[0009] Preferably, in the pickling process in S3, hydrofluoric acid can react slightly with the silicon dioxide on the crucible surface to remove silicon oxide impurities and some metal ions on the surface; hydrochloric acid and nitric acid can form soluble chlorides and nitrates with metal ions, thereby effectively removing metal contaminants on the crucible surface.

[0010] Preferably, in S4, under the action of ultrasound, tiny bubbles in the water are continuously generated and burst, generating a strong impact force, which can penetrate into the tiny pores and gaps on the surface of the crucible, removing residual particulate impurities and secondary pollutants that may be generated during the pickling process. Beneficial effects

[0011] The present invention provides a quartz crucible cleaning method. Compared with the existing technology, the method has the following advantages: the quartz crucible cleaning method can comprehensively and efficiently remove various contaminants on the surface of the quartz crucible, including metal ions, organic matter, and particulate impurities, by comprehensively utilizing multiple cleaning technologies such as mechanical scrubbing, high-pressure water gun flushing, plasma cleaning, pickling, and pure water ultrasonic cleaning. The surface cleanliness of the cleaned crucible meets the high standards required by the semiconductor and photovoltaic industries. During the cleaning process, various cleaning parameters, such as the concentration, temperature, and pickling time of the pickling solution, as well as the power and time of plasma cleaning, are reasonably controlled, avoiding the high concentration of strong acid and long-term strong plasma bombardment. The corrosion and damage to the crucible body ensures the strength and service life of the crucible, reduces the use of chemical reagents, especially the use of high-concentration strong acids, and reduces the generation of waste liquid and waste gas. At the same time, the cleaning system is equipped with complete waste liquid treatment and waste gas emission devices to properly treat the generated waste liquid and waste gas in accordance with environmental protection requirements. The supporting cleaning system realizes the automatic control of the cleaning process, reduces manual operation, improves cleaning efficiency and quality stability. The operator only needs to set the cleaning parameters through the touch screen, and the system can automatically complete the entire cleaning process, reducing labor intensity and the impact of human factors on cleaning quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a flow chart of the steps of the present invention. DETAILED DESCRIPTION

[0013] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0014] See also Figure 1 The present invention provides three technical solutions: a quartz crucible cleaning method, specifically including the following embodiments: Example 1

[0015] S1. Preprocessing: (1) Mechanical scrubbing: Place the quartz crucible to be cleaned in a dedicated scrubbing device, use a soft nylon brush or sponge brush with an appropriate amount of deionized water to perform a preliminary scrubbing of the outer and inner surfaces of the crucible. During the scrubbing process, the rotation speed of the brush is controlled at 125 r / min, and the scrubbing time is 6 minutes; (2) High-pressure water gun flushing: After brushing, use a high-pressure water gun to fully flush the crucible. The water pressure of the high-pressure water gun is set to 12 MPa and the flushing time is 3 minutes. S2. Plasma cleaning: (1) Equipment preparation: Place the pretreated quartz crucible into a plasma cleaning device equipped with a vacuum chamber, a radio frequency power supply, a gas supply system, and a plasma generator; (2) Vacuuming: Close the door of the vacuum chamber, start the vacuum pump, and reduce the vacuum degree in the chamber to 50 Pa to remove air and other impurity gases in the chamber and create a good environment for the generation of plasma; (3) Gas introduction: The working gas is introduced into the vacuum chamber. The working gas is a mixture of oxygen and argon, wherein the volume fraction of oxygen is 30% and the volume fraction of argon is 75%. The total flow rate of the gas is controlled at 55 sccm; (4) Plasma generation and cleaning: Turn on the RF power supply and adjust the RF power to 550W. At the same time, the physical bombardment of the plasma can remove some particulate impurities and metal ions on the surface of the crucible. The cleaning time is 17 minutes. S3, pickling: (1) Acid solution preparation: prepare pickling solution, which is composed of hydrofluoric acid, hydrochloric acid and nitric acid, where the concentration of hydrofluoric acid is 6%, the concentration of hydrochloric acid is 3%, the concentration of nitric acid is 3%, and the rest is deionized water; (2) Pickling process: immerse the quartz crucible after plasma cleaning in the pickling solution, the pickling temperature is controlled at 40 ° C, and the pickling time is 17 minutes; (3) Post-pickling treatment: After pickling, remove the crucible from the pickling solution and immediately rinse it with plenty of deionized water to remove the residual acid. The rinsing time should be no less than 5 minutes to ensure that the acid on the surface of the crucible is completely rinsed. S4, pure water ultrasonic cleaning: (1) Equipment preparation: Place the cleaned quartz crucible after pickling into a pure water ultrasonic cleaning device equipped with an ultrasonic generator, a cleaning tank, and a pure water circulation system; (2) Ultrasonic cleaning: inject ultrapure water with a conductivity of ≤0.1μS / cm into the cleaning tank, immerse the crucible completely in the water, turn on the ultrasonic generator, set the ultrasonic frequency to 60kHz, the ultrasonic power to 550W, and the cleaning time to 35min; (3) Pure water circulation and replacement: During the ultrasonic cleaning process, start the pure water circulation system to keep the water in the cleaning tank flowing and take away the pollutants cleaned in time. At the same time, replace the pure water every 20 minutes to ensure the cleaning effect; S5. Drying: (1) Equipment preparation: Place the quartz crucible after ultrasonic cleaning with pure water into the drying equipment, which uses a combination of hot air circulation and infrared heating and is equipped with a heating element, a fan and a temperature control system; (2) Drying process: Start the heating element and the fan, and gradually increase the temperature in the drying equipment to 115 ° C. The hot air circulates in the equipment under the action of the fan, so that the moisture on the surface of the crucible evaporates quickly. At the same time, the infrared heating can penetrate deep into the crucible and accelerate the volatilization of moisture. The drying time is 75 minutes, and the specific time is adjusted according to the size and moisture content of the crucible; (3) Cooling: After drying is completed, turn off the heating element and fan, allow the crucible to cool naturally to room temperature in the equipment, and then take out the crucible.

[0016] Example 2

[0017] S1. Preprocessing: (1) Mechanical scrubbing: Place the quartz crucible to be cleaned in a dedicated scrubbing device, use a soft nylon brush or sponge brush with an appropriate amount of deionized water to perform a preliminary scrubbing of the outer and inner surfaces of the crucible. During the scrubbing process, the rotation speed of the brush is controlled at 50 r / min, and the scrubbing time is 2 min. (2) High-pressure water gun flushing: After brushing, use a high-pressure water gun to fully flush the crucible. The water pressure of the high-pressure water gun is set to 5MPa and the flushing time is 1min. S2. Plasma cleaning: (1) Equipment preparation: Place the pretreated quartz crucible into a plasma cleaning device equipped with a vacuum chamber, a radio frequency power supply, a gas supply system, and a plasma generator; (2) Vacuuming: Close the door of the vacuum chamber, start the vacuum pump, and reduce the vacuum degree in the chamber to 1 Pa to remove air and other impurity gases in the chamber and create a good environment for the generation of plasma; (3) Gas introduction: The working gas is introduced into the vacuum chamber. The working gas is a mixture of oxygen and argon, wherein the volume fraction of oxygen is 10% and the volume fraction of argon is 50%. The total flow rate of the gas is controlled at 10 sccm. (4) Plasma generation and cleaning: Turn on the RF power supply and adjust the RF power to 100W. At the same time, the physical bombardment of the plasma can remove some particulate impurities and metal ions on the surface of the crucible. The cleaning time is 5 minutes. S3, pickling: (1) Acid solution preparation: prepare pickling solution, which is composed of hydrofluoric acid, hydrochloric acid and nitric acid, where the concentration of hydrofluoric acid is 1%, the concentration of hydrochloric acid is 1%, the concentration of nitric acid is 1%, and the rest is deionized water; (2) Pickling process: immerse the quartz crucible after plasma cleaning in the pickling solution, the pickling temperature is controlled at 20 ° C, and the pickling time is 5 minutes; (3) Post-pickling treatment: After pickling, remove the crucible from the pickling solution and immediately rinse it with plenty of deionized water to remove the residual acid. The rinsing time should be no less than 5 minutes to ensure that the acid on the surface of the crucible is completely rinsed. S4, pure water ultrasonic cleaning: (1) Equipment preparation: Place the cleaned quartz crucible after pickling into a pure water ultrasonic cleaning device equipped with an ultrasonic generator, a cleaning tank, and a pure water circulation system; (2) Ultrasonic cleaning: inject ultrapure water with a conductivity of ≤0.1μS / cm into the cleaning tank, immerse the crucible completely in the water, turn on the ultrasonic generator, set the ultrasonic frequency to 20kHz, the ultrasonic power to 100W, and the cleaning time to 10min; (3) Pure water circulation and replacement: During the ultrasonic cleaning process, start the pure water circulation system to keep the water in the cleaning tank flowing and take away the pollutants cleaned in time. At the same time, replace the pure water every 10 minutes to ensure the cleaning effect; S5. Drying: (1) Equipment preparation: Place the quartz crucible after ultrasonic cleaning with pure water into the drying equipment, which uses a combination of hot air circulation and infrared heating and is equipped with a heating element, a fan and a temperature control system; (2) Drying process: Start the heating element and the fan, and gradually increase the temperature in the drying equipment to 80°C. The hot air circulates in the equipment under the action of the fan, so that the moisture on the surface of the crucible evaporates quickly. At the same time, the infrared heating can penetrate deep into the crucible and accelerate the volatilization of moisture. The drying time is 30 minutes, and the specific time is adjusted according to the size and moisture content of the crucible; (3) Cooling: After drying is completed, turn off the heating element and fan, allow the crucible to cool naturally to room temperature in the equipment, and then take out the crucible.

[0018] Example 3

[0019] S1. Preprocessing: (1) Mechanical scrubbing: Place the quartz crucible to be cleaned in a dedicated scrubbing device, use a soft nylon brush or sponge brush, and an appropriate amount of deionized water to perform a preliminary scrubbing of the outer and inner surfaces of the crucible. During the scrubbing process, the rotation speed of the brush is controlled at 200 r / min, and the scrubbing time is 10 min. (2) High-pressure water gun flushing: After brushing, use a high-pressure water gun to fully flush the crucible. The water pressure of the high-pressure water gun is set to 20 MPa and the flushing time is 5 minutes. S2. Plasma cleaning: (1) Equipment preparation: Place the pretreated quartz crucible into a plasma cleaning device equipped with a vacuum chamber, a radio frequency power supply, a gas supply system, and a plasma generator; (2) Vacuuming: Close the door of the vacuum chamber, start the vacuum pump, and reduce the vacuum degree in the chamber to 100 Pa to remove air and other impurity gases in the chamber and create a good environment for the generation of plasma; (3) Gas introduction: The working gas is introduced into the vacuum chamber. The working gas is a mixture of oxygen and argon, wherein the volume fraction of oxygen is 50% and the volume fraction of argon is 90%. The total flow rate of the gas is controlled at 100 sccm. (4) Plasma generation and cleaning: Turn on the RF power supply and adjust the RF power to 1000W. At the same time, the physical bombardment of the plasma can remove some particulate impurities and metal ions on the surface of the crucible. The cleaning time is 30 minutes. S3, pickling: (1) Acid solution preparation: prepare pickling solution, which is composed of hydrofluoric acid, hydrochloric acid and nitric acid, where the concentration of hydrofluoric acid is 10%, the concentration of hydrochloric acid is 5%, the concentration of nitric acid is 5%, and the rest is deionized water; (2) Pickling process: immerse the quartz crucible after plasma cleaning in the pickling solution, the pickling temperature is controlled at 60 ° C, and the pickling time is 30 minutes; (3) Post-pickling treatment: After pickling, remove the crucible from the pickling solution and immediately rinse it with plenty of deionized water to remove the residual acid. The rinsing time should be no less than 5 minutes to ensure that the acid on the surface of the crucible is completely rinsed. S4, pure water ultrasonic cleaning: (1) Equipment preparation: Place the cleaned quartz crucible after pickling into a pure water ultrasonic cleaning device equipped with an ultrasonic generator, a cleaning tank, and a pure water circulation system; (2) Ultrasonic cleaning: inject ultrapure water with a conductivity of ≤0.1μS / cm into the cleaning tank, immerse the crucible completely in the water, turn on the ultrasonic generator, set the ultrasonic frequency to 100kHz, the ultrasonic power to 1000W, and the cleaning time to 60min; (3) Pure water circulation and replacement: During the ultrasonic cleaning process, start the pure water circulation system to keep the water in the cleaning tank flowing and take away the pollutants cleaned in time. At the same time, replace the pure water every 30 minutes to ensure the cleaning effect; S5. Drying: (1) Equipment preparation: Place the quartz crucible after ultrasonic cleaning with pure water into the drying equipment, which uses a combination of hot air circulation and infrared heating and is equipped with a heating element, a fan and a temperature control system; (2) Drying process: Start the heating element and the fan, and gradually increase the temperature in the drying equipment to 150°C. The hot air circulates in the equipment under the action of the fan, so that the moisture on the surface of the crucible evaporates quickly. At the same time, the infrared heating can penetrate deep into the crucible and accelerate the volatilization of moisture. The drying time is 120 minutes, and the specific time is adjusted according to the size and moisture content of the crucible; (3) Cooling: After drying is completed, turn off the heating element and fan, allow the crucible to cool naturally to room temperature in the equipment, and then take out the crucible.

[0020] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0021] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0022] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A quartz crucible cleaning method, characterized in that: The specific steps include: S1. Preprocessing: (1) Mechanical scrubbing: Place the quartz crucible to be cleaned in a dedicated scrubbing device, use a soft nylon brush or sponge brush, and an appropriate amount of deionized water to perform a preliminary scrubbing of the outer and inner surfaces of the crucible. During the scrubbing process, the rotation speed of the brush is controlled at 50-200 r / min, and the scrubbing time is 2-10 min. (2) High-pressure water gun flushing: After brushing, use a high-pressure water gun to fully flush the crucible. The water pressure of the high-pressure water gun is set to 5-20 MPa, and the flushing time is 1-5 minutes; S2. Plasma cleaning: (1) Equipment preparation: Place the pretreated quartz crucible into a plasma cleaning device equipped with a vacuum chamber, a radio frequency power supply, a gas supply system, and a plasma generator; (2) Vacuuming: Close the door of the vacuum chamber, start the vacuum pump, and reduce the vacuum degree in the chamber to 1-100 Pa to remove air and other impurity gases in the chamber and create a good environment for the generation of plasma; (3) Gas introduction: The working gas is introduced into the vacuum chamber. The working gas is a mixture of oxygen and argon, wherein the volume fraction of oxygen is 10%-50%, and the volume fraction of argon is 50%-90%. The total flow rate of the gas is controlled at 10-100 sccm; (4) Plasma generation and cleaning: Turn on the RF power supply and adjust the RF power to 100-1000W. At the same time, the physical bombardment of the plasma can remove some particulate impurities and metal ions on the surface of the crucible. The cleaning time is 5-30 minutes. S3, pickling: (1) Acid solution preparation: prepare pickling solution, which is composed of hydrofluoric acid, hydrochloric acid and nitric acid, wherein the concentration of hydrofluoric acid is 1%-10%, the concentration of hydrochloric acid is 1%-5%, the concentration of nitric acid is 1%-5%, and the rest is deionized water; (2) Pickling process: immerse the quartz crucible after plasma cleaning in the pickling solution, control the pickling temperature at 20-60 ° C, and the pickling time is 5-30 minutes; (3) Post-pickling treatment: After pickling, remove the crucible from the pickling solution and immediately rinse it with plenty of deionized water to remove the residual acid. The rinsing time should be no less than 5 minutes to ensure that the acid on the surface of the crucible is completely rinsed. S4, pure water ultrasonic cleaning: (1) Equipment preparation: Place the cleaned quartz crucible after pickling into a pure water ultrasonic cleaning device equipped with an ultrasonic generator, a cleaning tank, and a pure water circulation system; (2) Ultrasonic cleaning: inject ultrapure water with a conductivity of ≤0.1μS / cm into the cleaning tank, immerse the crucible completely in the water, turn on the ultrasonic generator, set the ultrasonic frequency to 20-100kHz, the ultrasonic power to 100-1000W, and the cleaning time to 10-60min; (3) Pure water circulation and replacement: During the ultrasonic cleaning process, start the pure water circulation system to keep the water in the cleaning tank flowing and take away the pollutants cleaned in time. At the same time, replace the pure water every 10-30 minutes to ensure the cleaning effect; S5. Drying: (1) Equipment preparation: Place the quartz crucible after ultrasonic cleaning with pure water into the drying equipment, which uses a combination of hot air circulation and infrared heating and is equipped with a heating element, a fan and a temperature control system; (2) Drying process: Start the heating element and the fan, and gradually increase the temperature in the drying equipment to 80-150℃. The hot air circulates in the equipment under the action of the fan, so that the moisture on the surface of the crucible evaporates quickly. At the same time, the infrared heating can penetrate deep into the crucible and accelerate the volatilization of moisture. The drying time is 30-120 minutes, and the specific time is adjusted according to the size and moisture content of the crucible. (3) Cooling: After drying is completed, turn off the heating element and fan, allow the crucible to cool naturally to room temperature in the equipment, and then take out the crucible.

2. The method for cleaning a quartz crucible according to claim 1, wherein: The mechanical scrubbing in S1 is to remove larger particles of impurities and some loose pollutants attached to the surface of the crucible.

3. The method for cleaning a quartz crucible according to claim 1, wherein: The high-pressure water gun flushing in S1 can be adjusted in flushing angle according to the shape of the crucible to ensure that the water flow can cover all parts of the crucible and further flush away residual particulate impurities and dirt generated by brushing.

4. The method for cleaning a quartz crucible according to claim 1, wherein: In S2, plasma generation and cleaning ionize the working gas under the action of the radio frequency electric field to generate plasma. The active particles in the plasma chemically react with the organic matter on the crucible surface, decomposing it into small molecules such as carbon dioxide and water, and then discharge it out of the chamber through the vacuum pump.

5. The method for cleaning a quartz crucible according to claim 1, wherein: In the pickling process in S3, hydrofluoric acid can react slightly with the silicon dioxide on the crucible surface to remove silicon oxide impurities and some metal ions on the surface; hydrochloric acid and nitric acid can form soluble chlorides and nitrates with metal ions, thereby effectively removing metal contaminants on the crucible surface.

6. The method for cleaning a quartz crucible according to claim 1, wherein: In S4, under the action of ultrasound, tiny bubbles in the water are continuously generated and burst, generating a strong impact force that can penetrate into the tiny pores and gaps on the crucible surface, removing residual particulate impurities and secondary pollutants that may be generated during the pickling process.

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