An environmental protection intelligent manufacturing process of ultra-high purity quartz sand for semiconductor by hot phosphoric acid hydrogen reduction system

Abstract

The application relates to the technical field of non-metallic mineral purification materials, and discloses an environment-friendly intelligent manufacturing process of an ultra-high-purity quartz sand thermal hydrogen phosphate thermal reduction system for semiconductors, which comprises the following steps: firstly, pretreating raw materials, soaking and washing high-purity quartz raw ore, three-stage crushing and grading, color selection, hydrogen calcination, high-pressure thermal phosphoric acid leaching, ball milling and cyclone grading, preparing raw materials with a particle size of 0.1-0.5 mm, a purity of more than 4N and controllable impurities, then high-gradient magnetic separation, fluorine-free and acid-free ultrasonic flotation, normal-pressure microwave plasma, iterative high-pressure thermal phosphoric acid leaching-vacuum microwave hydrogen thermal reduction-high-purity high-pressure thermal phosphoric acid leaching technology, removing inclusions and lattice impurities through fine purification, preparing high-purity quartz sand with a purity of 5N and above, further removing nanoscale inclusions and lattice impurities through vacuum microwave hydrogen mixed plasma, preparing ultra-high-purity quartz sand with a purity of more than 6N, and the total amount of difficult-to-remove impurities such as Al, Ti, Li, B and alkali metals is less than 0.1 ppm.

Description

Technical Field

[0001] This invention relates to the field of non-metallic mineral purification materials technology, specifically to an environmentally friendly and intelligent manufacturing process for a thermal reduction system of ultra-high purity quartz sand for semiconductors using hydrogen phosphate. Background Technology

[0002] High-purity silica sand is a key basic material in high-end manufacturing fields such as semiconductors, optoelectronics, and photovoltaics. As chip manufacturing processes advance to below 3nm, the purity requirement for silica sand must reach 6N (99.9999%) or higher, and impurities such as alkali metals, aluminum, titanium, and boron must be controlled below 0.1ppm. Currently, my country relies heavily on imports for high-end products, posing significant supply chain security risks and highlighting the urgent need for domestic substitution.

[0003] Existing high-purity quartz purification processes have significant shortcomings: First, high-quality ore sources are scarce, and domestic vein quartz ore has high impurities and complex inclusions and lattice impurities, making it difficult to adapt to traditional processes and resulting in low purification efficiency. Second, there is significant environmental pressure, as mainstream technologies use large amounts of highly corrosive reagents such as hydrofluoric acid, hydrochloric acid, and nitric acid, leading to high costs for treating fluoride- and chlorine-containing wastewater and exhaust gases, and significant pollution risks. Third, the ability to remove impurities at a deep level is insufficient; conventional physical sorting and acid leaching are insufficient to remove submicron-nanometer-sized inclusions and lattice substitution impurities, making it impossible to consistently achieve 6N-level purity. Fourth, mass production stability is poor; in large-scale production, parameter control is crude, equipment is prone to introducing secondary pollution, batch consistency is poor, and it is difficult to meet the stringent certification requirements of semiconductor manufacturers. Fifth, the process integration is low, lacking a synergistic system for physical sorting, chemical leaching, high-temperature reduction, and plasma impurity removal, resulting in long processes, high energy consumption, and large reagent consumption.

[0004] Based on this, it is necessary to propose an environmentally friendly and intelligent manufacturing process for semiconductors using a thermal reduction system of ultra-high purity quartz sand and hydrogen phosphate. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an environmentally friendly and intelligent manufacturing process for semiconductors using a thermal reduction system of ultra-high purity quartz sand and hydrogen phosphate. This process offers advantages such as being fluorine-free and chlorine-free, environmentally friendly, capable of deep impurity removal, and intelligently stable, thus solving the problems mentioned in the background technology.

[0006] This invention provides the following technical solution: an environmentally friendly and intelligent manufacturing process for semiconductor ultra-high purity quartz sand using a thermal hydrogen phosphate reduction system, comprising the following steps: Step 1: Raw material pretreatment: High-purity quartz ore is soaked and washed, crushed and classified in three stages, color sorted, hydrogenated and calcined, leached with hot phosphoric acid under high pressure, and classified by ball milling and cyclone grading to obtain raw materials with a particle size of 0.1-0.5 mm, a purity of 4N or higher, and controllable impurities. Step 2: High gradient magnetic separation: Vertical ring pulsating high gradient wet magnetic separation is used to remove magnetic impurities; Step 3: Fluorine-free and acid-free ultrasonic flotation combined with atmospheric pressure microwave plasma impurity removal: ultrasonic flotation and cleaning under neutral / weakly alkaline conditions, followed by atmospheric pressure microwave plasma removal of gangue minerals and grain boundary impurities; Step 4: Iterative fine purification: hot phosphoric acid high-pressure leaching—vacuum microwave hydrogen thermal reduction—high-purity hot phosphoric acid high-pressure leaching to remove inclusions and lattice impurities, and obtain high-purity quartz sand of 5N and above. Step 5: Final purification by plasma: Vacuum microwave hydrogen mixed plasma removes nanoscale inclusions and lattice impurities to obtain ultra-high purity quartz sand with a purity of 6N or higher. Step Six: Quality Control and Product Handling: Vacuum cooling and quality inspection; qualified products are vacuum-packed and stored in a Class 100 cleanroom; process exhaust gas, wastewater, and waste residue are treated to meet standards; hot phosphoric acid waste liquid is recycled.

[0007] Preferably, the high-purity quartz ore standard in step one is as follows: SiO2 mass fraction > 3N, total impurities < 50 μg / g, of which Al < 30 μg / g, Ti < 10 μg / g, Na < 8 μg / g, K < 8 μg / g, Li < 5 μg / g, Ca < 5 μg / g, Fe < 3 μg / g, P < 2 μg / g, B < 1 μg / g, and trace amounts of radioactive elements and gas-liquid inclusions.

[0008] Preferably, in step one, the crushing and grading process is as follows: the jaw crusher coarsely crushes to 10-30mm, the cone crusher medium crushes to 5-10mm, and the double roll crusher finely crushes to 1-5mm; the inner wall of the equipment in contact with quartz is made of a custom-made anti-pollution material.

[0009] Preferably, step one, hydrogenation calcination, involves using a high-purity argon and hydrogen mixture of 4N or higher, a hydrogenation temperature of 600–1500℃, a vacuum degree of 0.1–0.01 Pa, a Class 1000 clean environment, and a calcination time of 1–8 hours.

[0010] Preferably, the hot phosphoric acid high-pressure leaching in steps one and four uses a multi-functional microwave acid leaching kettle with a phosphoric acid concentration of 20% to 50%, a liquid-to-solid ratio of 2:1 to 5:1, a pressure of 2 to 10 MPa, and a temperature of 200 to 250°C; the high-purity hot phosphoric acid leaching in step (4) uses electronic-grade phosphoric acid with a pressure of 2 to 5 MPa and a temperature of 200 to 220°C.

[0011] Preferably, in step two, high gradient magnetic separation, the background magnetic field is 1.5-2.0T, the slurry concentration is 25-30%, the pulse frequency is 200-300 times / min, and the proportion of feed particles with a particle size of -0.074mm is ≥80%.

[0012] Preferably, in step three, ultrasonic flotation, the pH is 7-9, a combination of sodium dodecyl sulfonate and dodecylamine is used as the collector, supplemented by water glass for suppression, the ultrasonic frequency is 20-40 kHz, and the temperature is 30-40 °C; the atmospheric pressure microwave plasma is: microwave frequency 2.450 GHz, power 10-50 kW, temperature 1000-1500 °C, and atmospheric pressure treatment for 30-120 min.

[0013] Preferably, step four, vacuum microwave hydrogen thermal reduction, involves using a high-purity argon and hydrogen mixture of 5N or higher, at a temperature of 600–1200℃, a vacuum of 0.1–0.01 Pa, in a Class 100 clean environment, for 30–240 minutes.

[0014] Preferably, step five, vacuum microwave plasma, employs a high-purity argon and hydrogen mixture of 6N or higher, at a temperature of 600–1500°C and a vacuum degree of 10⁻²–10⁻. 4 Pa, Class 100 clean environment, treatment for 20-180 minutes, total impurities in the product <0.1ppm.

[0015] Preferably, the entire process uses ultrapure water with a resistivity ≥18.2MΩ・cm, and the gas flow rate is precisely controlled by a mass flow controller; the exhaust gas is treated to meet emission standards, the waste residue is harmlessly treated by a microwave plasma incinerator, the wastewater is reused to produce ultrapure water, and the hot phosphoric acid waste liquid is recycled.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This environmentally friendly and intelligent manufacturing process for ultra-high purity quartz sand in semiconductors utilizes a thermal hydrogen phosphate reduction system and a microwave plasma synergistic purification system. Compared to traditional high-purity quartz preparation processes, it can stably increase the purity of quartz sand to above 6N, with total impurities below 0.1ppm. It can deeply remove microscopic inclusions, submicron-nanoscale inclusions, and lattice substitution impurities from quartz, and is particularly effective in removing difficult-to-remove impurities such as Al, Ti, Li, B, and alkali metals. The purity, uniformity, and batch stability of the product fully meet the stringent requirements of advanced semiconductor processes, effectively solving the technical bottleneck of traditional processes that cannot achieve ultra-high purity deep purification.

[0017] This environmentally friendly and intelligent manufacturing process for semiconductors uses ultra-high purity quartz sand in a hot phosphoric acid hydrogen thermal reduction system. The entire process adopts a green purification route that is free of fluorine, chlorine, and nitrate. Hot phosphoric acid high-pressure leaching replaces the highly corrosive hydrofluoric acid system, and hydrogen reduction and microwave plasma physicochemical synergistic impurity removal are used to significantly reduce the pressure of wastewater, waste gas, and waste residue treatment. At the same time, the hot phosphoric acid waste liquid can be purified and recycled, and the production wastewater can be treated and reused for the preparation of ultrapure water. The overall process has the characteristics of low corrosion, low emission, low energy consumption, and high recycling, which significantly reduces production costs and environmental governance pressure, and is in line with the policy orientation of green intelligent manufacturing and sustainable development.

[0018] This environmentally friendly and intelligent manufacturing process for ultra-high purity quartz sand in semiconductors utilizes a thermal hydrogen phosphate reduction system. It relaxes the quality requirements for high-purity quartz ore, making it compatible with various domestic mineral sources such as pegmatite and vein quartz, thus overcoming the reliance on imported high-quality minerals. The entire process employs intelligent equipment and precise parameter control, with custom-designed anti-contamination materials used in equipment contact areas to prevent secondary pollution. This enables continuous and stable mass production, effectively improving product consistency and production efficiency. This process breaks the foreign technology and market monopoly, significantly increasing my country's self-sufficiency rate for ultra-high purity quartz sand, strongly safeguarding the security of the semiconductor industry chain and supply chain, and promoting the domestic substitution of high-end quartz materials and the high-quality development of the industry. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1 An environmentally friendly and intelligent manufacturing process for semiconductors using ultra-high purity quartz sand thermal hydrogen phosphate thermal reduction system includes the following steps: Step 1: Raw material pretreatment: High-purity quartz ore is soaked and washed, crushed and classified in three stages, color sorted, hydrogenated and calcined, leached with hot phosphoric acid under high pressure, and classified by ball milling and cyclone grading to obtain raw materials with a particle size of 0.1-0.5 mm, a purity of 4N or higher, and controllable impurities. Step 2: High gradient magnetic separation: Vertical ring pulsating high gradient wet magnetic separation is used to remove magnetic impurities; Step 3: Fluorine-free and acid-free ultrasonic flotation combined with atmospheric pressure microwave plasma impurity removal: ultrasonic flotation and cleaning under neutral / weakly alkaline conditions, followed by atmospheric pressure microwave plasma removal of gangue minerals and grain boundary impurities; Step 4: Iterative fine purification: hot phosphoric acid high-pressure leaching—vacuum microwave hydrogen thermal reduction—high-purity hot phosphoric acid high-pressure leaching to remove inclusions and lattice impurities, and obtain high-purity quartz sand of 5N and above. Step 5: Final purification by plasma: Vacuum microwave hydrogen mixed plasma removes nanoscale inclusions and lattice impurities to obtain ultra-high purity quartz sand with a purity of 6N or higher. Step Six: Quality Control and Product Handling: Vacuum cooling and quality inspection; qualified products are vacuum-packed and stored in a Class 100 cleanroom; process exhaust gas, wastewater, and waste residue are treated to meet standards; hot phosphoric acid waste liquid is recycled.

[0022] Specifically, the overall process flow is divided into four stages and six steps. The four stages are: raw material pretreatment: producing qualified raw materials with a purity of 4N or higher; high-purity purification: magnetic separation, flotation plasma, iterative acid leaching and hydrogen reduction to produce products with a purity of 5N or higher; ultra-high purity final purification: vacuum microwave hydrogen mixing plasma to produce products with a purity of 6N or higher; quality control and packaging: vacuum cooling, quality inspection, and clean packaging. The six steps are: (1) Raw material pretreatment Raw ore standards: SiO2 > 3N, total impurities < 50 μg / g, key impurities meet standards, and radioactivity and trace amounts of gas-liquid inclusions are acceptable. Soaking: 20%~50% phosphoric acid, liquid-solid ratio 2:1~5:1, pressure 2~10MPa, 200~250℃, 2~24h, high pressure rinsing; Crushing and grading: coarse crushing 10-30mm → medium crushing 5-10mm → fine crushing 1-5mm; Color sorting: Particle size 0.08~5mm, near white threshold, air valve pressure 0.4~0.6MPa; Hydrogenation calcination: 4N high-purity argon / hydrogen, 600~1500℃, 0.1~0.01Pa, Class 1000 cleanroom, 1~8h; Hot phosphoric acid high-pressure leaching: 30%~50% phosphoric acid, 2~10MPa, 200~250℃, 1~8h, microwave cleaning; Ball milling and classification: Ball milling for 1–8 hours, followed by cyclone classification to obtain 0.1–0.5 mm raw material with a purity ≥4N. (2) High gradient magnetic separation Vertical ring pulsating high-gradient wet magnetic separation, magnetic field 1.5~2.0T, pulp concentration 25~30%, pulsation 200~300 times / min, -0.074mm content ≥80%, efficiently removes magnetic impurities. (3) Fluorine-free and acid-free ultrasonic flotation combined with atmospheric pressure microwave plasma impurity removal Slurry preparation and flotation: pH 7-9, concentration 20-40%; SDS to DDA collector ratio 1:1-2:1, water glass inhibition; ultrasonication 20-40kHz, 30-40℃, flotation 5-60min; Plasma: 2.450GHz microwave, 10~50kW, 1000~1500℃, normal pressure, O2 atmosphere, 30~120min, to remove gangue and grain boundary impurities; (4) Iterative fine purification Hot phosphoric acid high-pressure leaching: 20%~50% phosphoric acid, 2~10MPa, 200~250℃, 1~8h, microwave cleaning and drying; Vacuum microwave hydrogen thermal reduction: 5N high-purity argon / hydrogen, 600~1200℃, 0.1~0.01Pa, Class 100 cleanroom, 30~240min; High-purity hot phosphoric acid leaching: 20%–50% electronic grade phosphoric acid, 2–5 MPa, 200–220℃, 1–2 h; It can be repeatedly iterated to precisely remove inclusions and produce high-purity quartz sand with an N of 5 or higher and impurities of <0.8ppm; (5) Iterative fine purification Hot phosphoric acid high-pressure leaching: 20%~50% phosphoric acid, 2~10MPa, 200~250℃, 1~8h, microwave cleaning and drying; Vacuum microwave hydrogen thermal reduction: 5N high-purity argon / hydrogen, 600~1200℃, 0.1~0.01Pa, Class 100 cleanroom, 30~240min; High-purity hot phosphoric acid leaching: 20%–50% electronic grade phosphoric acid, 2–5 MPa, 200–220℃, 1–2 h; It can be repeatedly iterated to precisely remove inclusions and produce high-purity quartz sand with an N of 5 or higher and impurities of <0.8ppm; (6) Quality control and product collection Vacuum cooling: 0.1~0.01Pa, 6N argon gas cooling, 20~50℃ / min to 20~25℃, Class 100 cleanroom, humidity ≤40%; Quality inspection and packaging: After purity, impurities, and particle size meet the standards, the product is vacuum-packed in a Class 100 cleanroom and put into storage. Environmental treatment: exhaust gas meets emission standards, waste residue is incinerated by plasma, wastewater is reused, and phosphoric acid waste liquid is recycled.

[0023] As a preferred technical solution of the present invention, the standard for high-purity quartz ore in step one is: SiO2 mass fraction > 3N, total impurities < 50 μg / g, of which Al < 30 μg / g, Ti < 10 μg / g, Na < 8 μg / g, K < 8 μg / g, Li < 5 μg / g, Ca < 5 μg / g, Fe < 3 μg / g, P < 2 μg / g, B < 1 μg / g, and trace amounts of radioactive elements and gas-liquid inclusions.

[0024] As a preferred technical solution of the present invention, the crushing and grading in step one is as follows: the jaw crusher coarsely crushes to 10-30mm, the cone crusher medium crushes to 5-10mm, and the double roll crusher finely crushes to 1-5mm; the inner wall of the equipment in contact with quartz is made of a custom-made anti-pollution material.

[0025] As a preferred technical solution of the present invention, the first step of hydrogenation calcination involves using a high-purity argon and hydrogen mixture of 4N or higher, a hydrogenation temperature of 600–1500°C, a vacuum degree of 0.1–0.01 Pa, a Class 1000 clean environment, and a calcination time of 1–8 hours.

[0026] As a preferred technical solution of the present invention, the hot phosphoric acid high-pressure leaching in steps one and four adopts a multi-functional microwave acid leaching kettle with a phosphoric acid concentration of 20% to 50%, a liquid-solid ratio of 2:1 to 5:1, a pressure of 2 to 10 MPa, and a temperature of 200 to 250°C; the high-purity hot phosphoric acid leaching in step (4) adopts electronic-grade phosphoric acid with a pressure of 2 to 5 MPa and a temperature of 200 to 220°C.

[0027] As a preferred embodiment of the present invention, step three, ultrasonic flotation, involves a pH of 7-9, using a combination of sodium dodecyl sulfonate and dodecylamine as a collector, supplemented by water glass for suppression, with an ultrasonic frequency of 20-40 kHz and a temperature of 30-40 °C. The atmospheric pressure microwave plasma process involves a microwave frequency of 2.450 GHz, a power of 10-50 kW, a temperature of 1000-1500 °C, and atmospheric pressure treatment for 30-120 min.

[0028] As a preferred technical solution of the present invention, the entire process uses ultrapure water with a resistivity ≥18.2MΩ・cm, and the gas flow rate is precisely controlled by a mass flow controller; the exhaust gas is treated to meet emission standards, the waste residue is harmlessly treated by a microwave plasma incinerator, the wastewater is reused to produce ultrapure water, and the hot phosphoric acid waste liquid is recycled.

[0029] Example 1 Raw material pretreatment: The raw ore meets the 3N standard, is soaked in 30% phosphoric acid at a liquid-to-solid ratio of 2:1, at 5MPa and 200℃ for 8 hours; it is then crushed to 1-5mm in three stages; color sorting is performed; hydrogenation and calcination are carried out at 1000℃ and 0.1Pa for 2 hours; 50% phosphoric acid is leached at 5MPa and 200℃ for 2 hours; ball milling is performed for 4 hours, and the ore is classified to obtain 0.1-0.5mm, 4N raw material. Magnetic separation: 1.8T magnetic field, 25% concentration, 250 pulses / min; Flotation plasma: pH 8, SDS:DDA = 1:1, ultrasonic 30kHz, 30℃, flotation for 50min; 30kW plasma, 1000℃, atmospheric pressure, 50min; Iterative purification: leaching with 30% phosphoric acid at 3MPa, 200℃ for 2h; hydrogen reduction at 1000℃, 0.01Pa for 120min; leaching with 30% electronic grade phosphoric acid at 3MPa, 200℃ for 3h to obtain 5N product; Final purification: 1000℃, 10⁻³Pa, 50min, to obtain products with 6N or higher; Quality control and packaging: vacuum cooling, Class 100 packaging, and warehousing after passing quality inspection.

[0030] Example 2 Raw material pretreatment: 30% phosphoric acid soaking, liquid-solid ratio 3:1, 5MPa, 200℃, 8h; hydrogenation calcination 1100℃, 0.1Pa, 1.5h; 40% phosphoric acid leaching, 4MPa, 200℃, 1.5h. Magnetic separation: 1.8T magnetic field, concentration 25%; Flotation plasma: pH 8, 35℃, flotation for 40 min; 40kW plasma, 1100℃, 40 min; Iterative purification: 40% phosphoric acid leaching, 4 MPa, 200℃, 3 h; hydrogen reduction, 1100℃, 0.01 Pa, 120 min; 40% electronic grade phosphoric acid leaching, 5 MPa, 200℃, 3 h; Final purification: 1100℃, 10⁻³Pa, 40min, to obtain products with 6N or higher; Quality control and packaging: Same as in Example 1.

[0031] Example 3 Raw material pretreatment: 30% phosphoric acid soaking, liquid-solid ratio 4:1, 5MPa, 200℃, 8h; hydrogenation calcination 1200℃, 0.1Pa, 1h; 30% phosphoric acid leaching, 3MPa, 200℃, 1h; Magnetic separation: 2.0T magnetic field, concentration 25%; Flotation plasma: pH 8, 40℃, flotation for 30 min; 50kW plasma, 1200℃, 30 min; Iterative purification: 50% phosphoric acid leaching, 5 MPa, 200℃, 4 h; hydrogen reduction, 1200℃, 0.01 Pa, 120 min; 40% electronic grade phosphoric acid leaching, 5 MPa, 200℃, 4 h; Final purification: 1200℃, 10⁻³Pa, 30min, to obtain products with 6N or higher; Quality control packaging: Same as in Example 1.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly and intelligent manufacturing process for semiconductors using a thermal hydrogen phosphate reduction system based on ultra-high purity quartz sand, characterized in that... Includes the following steps: Step 1: Raw material pretreatment: High-purity quartz ore is soaked and washed, crushed and classified in three stages, color sorted, hydrogenated and calcined, leached with hot phosphoric acid under high pressure, and classified by ball milling and cyclone grading to obtain raw materials with a particle size of 0.1-0.5 mm, a purity of 4N or higher, and controllable impurities. Step 2: High gradient magnetic separation: Vertical ring pulsating high gradient wet magnetic separation is used to remove magnetic impurities; Step 3: Fluorine-free and acid-free ultrasonic flotation combined with atmospheric pressure microwave plasma impurity removal: ultrasonic flotation and cleaning under neutral / weakly alkaline conditions, followed by atmospheric pressure microwave plasma removal of gangue minerals and grain boundary impurities; Step 4: Iterative fine purification: hot phosphoric acid high-pressure leaching—vacuum microwave hydrogen thermal reduction—high-purity hot phosphoric acid high-pressure leaching to remove inclusions and lattice impurities, and obtain high-purity quartz sand of 5N and above. Step 5: Final purification by plasma: Vacuum microwave hydrogen mixed plasma removes nanoscale inclusions and lattice impurities to obtain ultra-high purity quartz sand with a purity of 6N or higher. Step Six: Quality Control and Product Handling: Vacuum cooling and quality inspection; qualified products are vacuum-packed and stored in a Class 100 cleanroom; process exhaust gas, wastewater, and waste residue are treated to meet standards; hot phosphoric acid waste liquid is recycled.

2. The environmentally friendly intelligent manufacturing process for a semiconductor ultra-high purity quartz sand thermal hydrogen phosphate thermal reduction system according to claim 1, characterized in that: The standard for high-purity quartz ore in step one is as follows: SiO2 mass fraction > 3N, total impurities < 50 μg / g, of which Al < 30 μg / g, Ti < 10 μg / g, Na < 8 μg / g, K < 8 μg / g, Li < 5 μg / g, Ca < 5 μg / g, Fe < 3 μg / g, P < 2 μg / g, B < 1 μg / g, and trace amounts of radioactive elements and gas-liquid inclusions.

3. The environmentally friendly intelligent manufacturing process for a semiconductor ultra-high purity quartz sand thermal hydrogen phosphate thermal reduction system according to claim 1, characterized in that: Step one involves multi-stage crushing and grading: a jaw crusher coarsely crushes to 10-30mm, a cone crusher medium crushes to 5-10mm, and a double roll crusher finely crushes to 1-5mm; the inner wall of the equipment in contact with quartz is made of a custom-made anti-pollution material.

4. The environmentally friendly intelligent manufacturing process for a semiconductor ultra-high purity quartz sand thermal hydrogen phosphate thermal reduction system according to claim 1, characterized in that: Step 1, hydrogenation calcination: A mixture of high-purity argon and hydrogen gas of 4N or higher is used, the hydrogenation temperature is 600-1500℃, the vacuum degree is 0.1-0.01Pa, the environment is a Class 1000 cleanroom, and the calcination time is 1-8 hours.

5. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: The hot phosphoric acid high-pressure leaching in steps one and four uses a multi-functional microwave acid leaching kettle with a phosphoric acid concentration of 20% to 50%, a liquid-solid ratio of 2:1 to 5:1, a pressure of 2 to 10 MPa, and a temperature of 200 to 250°C. The high-purity hot phosphoric acid leaching in step (4) uses electronic-grade phosphoric acid with a pressure of 2 to 5 MPa and a temperature of 200 to 220°C.

6. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: The second step, high gradient magnetic separation, involves a background magnetic field of 1.5–2.0T, a slurry concentration of 25–30%, a pulse frequency of 200–300 times / min, and a feed particle size of -0.074mm accounting for ≥80%.

7. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: Step three, ultrasonic flotation: pH 7-9, using a combination of sodium dodecyl sulfonate and dodecylamine as collectors, supplemented by water glass suppression, ultrasonic frequency 20-40kHz, temperature 30-40℃; the atmospheric pressure microwave plasma: microwave frequency 2.450GHz, power 10-50kW, temperature 1000-1500℃, atmospheric pressure treatment for 30-120min.

8. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: Step four, vacuum microwave hydrogen thermal reduction, involves using a high-purity argon and hydrogen mixture of 5N or higher, at a temperature of 600–1200℃, a vacuum of 0.1–0.01 Pa, in a Class 100 clean environment, for 30–240 minutes.

9. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: Step five, vacuum microwave plasma, employs a high-purity argon and hydrogen mixture of 6N or higher, at a temperature of 600–1500°C and a vacuum degree of 10. -2 ~10 -4 Pa, Class 100 clean environment, treatment for 20-180 minutes, total impurities in the product <0.1ppm.

10. The environmentally friendly intelligent manufacturing process for ultra-high purity quartz sand in semiconductors, characterized by thermal reduction of hydrogen phosphate as described in claim 1, is characterized in that: The entire process uses ultrapure water with a resistivity ≥18.2MΩcm, and the gas flow rate is precisely controlled by a mass flow controller; the exhaust gas is treated to meet emission standards, the waste residue is harmlessly treated by a microwave plasma incinerator, the wastewater is reused to produce ultrapure water, and the hot phosphoric acid waste liquid is recycled.

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