An environment-friendly process and equipment for intelligent continuous targeted removal of inclusions and lattice impurities in ultra-high purity quartz sand for semiconductors

Abstract

This invention relates to the field of non-metallic mineral purification material technology and equipment manufacturing technology, and discloses an environmentally friendly process and equipment for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors. The process includes the following steps: First, high-purity quartz ore is pretreated by soaking, washing, crushing, grading, color matching, magnetic separation, flotation, and acid leaching to obtain qualified material with a particle size of 0.1–0.3 mm and a purity ≥4N5, which is then loaded into the feeding system silo for later use. Next, a three-stage targeted impurity removal system using hydrogenation, acid leaching, and plasma technology is employed to purify the 4N5 grade raw material to 6N and above in one step, with single-element impurities below 0.1 ppm. This precisely removes micro-nano inclusions and difficult-to-remove lattice impurities, ensuring the product fully meets the stringent purity requirements of high-end semiconductor manufacturing and effectively improving the insulation, heat resistance, and service life of downstream chips and quartz devices.

Description

Technical Field

[0001] This invention relates to the field of non-metallic mineral purification material technology and equipment manufacturing technology, specifically to an environmentally friendly process and equipment for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors. Background Technology

[0002] High-purity quartz sand is a key basic material in semiconductor manufacturing, high-end optics, photovoltaics, and fiber optic communications. In particular, quartz materials for semiconductors require a purity of 6N or higher and an impurity content of less than 0.1 ppm, with extremely stringent control over inclusions and lattice impurities. Natural quartz ore commonly contains gangue minerals, micro- and nano-inclusions, and lattice impurities. Among these, inclusions and lattice impurities are difficult to remove using conventional methods and are the core factors restricting the improvement of purity.

[0003] Traditional purification processes, primarily involving chlorination roasting and hydrofluoric acid leaching, have significant drawbacks: First, impurity removal is incomplete, with low efficiency in removing lattice titanium, aluminum, and nano-inclusions, making it difficult to consistently achieve 6N-level purity. Second, there are significant environmental and safety risks, as chlorine and hydrofluoric acid are highly toxic and corrosive, leading to substantial waste treatment pressures and failing to meet green production requirements. Third, high equipment investment, energy consumption, and reagent consumption result in persistently high production costs. Fourth, intermittent production and low automation levels lead to poor batch-to-batch product stability, failing to meet the high standards of the semiconductor industry. Existing improved technologies have yet to achieve targeted, efficient, and environmentally friendly integrated impurity removal, making it difficult to simultaneously address the challenges of inclusion bursting and lattice impurity removal.

[0004] Based on this, it is necessary to propose an environmentally friendly process and equipment for the intelligent, continuous, targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an environmentally friendly process and equipment for the intelligent, continuous, and targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors. This new environmentally friendly process and equipment offers the advantages of being fluorine-free and chlorine-free, intelligently continuous, and deeply precise in removing inclusions and lattice impurities, thus solving the problems mentioned in the background art.

[0006] This invention provides the following technical solution: an environmentally friendly process for intelligent, continuous, targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors, comprising the following steps: Step 1: Material Preparation: After pretreatment, magnetic separation, flotation, and acid leaching, the high-purity quartz ore is loaded into the feed system silo for later use. Raw material requirements: SiO2 ≥ 3N, total impurities < 100 μg / g; Preferred: 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; particle size 0.1~0.3mm, purity ≥ 4N, qualified material purity reaches 4N5, total impurities < 50 μg / g; Step 2: The empty suction gun feeds the raw material into the vacuum double cone feeder at a feed / discharge speed of 0.2-2 kg / min; Step 3: Hydrogenation-Coordinated Acid Leaching Targeted Impurity Removal: Vacuum microwave hydrogenation removes lattice impurities, simultaneous microwave gradient acid leaching removes bursting micro / nano inclusions, and ultrapure water microwave cleaning and drying; Hydrogenation parameters: Ar / H2≥5N, mixed gas flow rate 10~100sccm, temperature 600~1200℃, time 30~240min, vacuum degree 0.1~0.01Pa; Acid leaching uses high-purity phosphoric acid gradient leaching: 20%~40%, 40%~60%, 60%~80%, liquid-solid ratio 2:1~5:1, pressure 2~10MPa, temperature 200~250℃, time 1~4h, ultrapure water resistivity ≥18.2MΩ・cm, drying temperature 200~250℃; Total impurities after removal <8ppm; Step 4: Plasma-targeted impurity removal: High-energy hydrogen mixed plasma is used for fine purification to remove residual nanoscale inclusions and lattice impurities; Parameters: Ar / H2≥6N, mixed gas flow rate 10~150sccm, vacuum degree 10⁻²~10⁻ 4 Pa, temperature 600–1500℃, time 20–180 min; single element impurities <0.1 ppm; Step 5: Quality Control and Collection Processing: Vacuum cooling, testing, vacuum packaging and warehousing; cooling vacuum degree 0.1~0.01Pa, cooling medium ≥6NAr, flow rate 5~100cm³ / min, cooling rate 20~50℃ / min, cooling to 0~25℃; product purity ≥6N, single impurity <0.1ppm.

[0007] Preferably, the qualified raw material in step one has a particle size of 0.1-0.3 mm, a purity of 4N5, and a total impurity content of <50 μg / g.

[0008] Preferably, in step three, the cyclic parameters enable stepwise targeted impurity removal, and in step four, temperature control, speed control, and time control are used to achieve fine purification of single particles.

[0009] Preferably, the entire process is completed in a Class 100 clean environment with humidity ≤40%, and the exhaust gas, wastewater, waste acid, and waste residue are all treated to meet standards. Waste acid is recycled and wastewater is reused to produce ultrapure water.

[0010] An environmentally friendly device for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors includes: a furnace shell, a feeding system, a hydrogenation targeted impurity removal system, an acid leaching targeted impurity removal system, a plasma targeted impurity removal system, a quality control and product collection and processing system, and a process auxiliary system. The feeding system includes a hopper, a vacuum suction gun, and a vacuum double cone feeder; The hydrogenation targeted impurity removal system includes a vacuum interface I, a feed inlet I, a feed and discharge vacuum tube and sealing seat I, a rotary sealing device I, a feed pipe I, a heating device I, a reactor, a magnetron I, a feed and discharge vacuum tube and sealing seat II, an exhaust port and waste gas treatment interface I, a temperature controller I, an inert gas and flow meter interface I, and a reaction gas and flow meter interface I. The acid leaching targeted impurity removal system includes a feed inlet II, an exhaust port and waste gas treatment interface II, a pressure gauge I, an ultrapure water inlet, a temperature controller II, an auxiliary material inlet, a magnetron II, a gradient reaction circulation chamber, a multi-functional microwave rotary reaction chamber, a three-way valve I, a three-way valve II, a three-way valve III, a microwave cleaning and drying chamber, and a waste liquid discharge interface. The plasma targeted impurity removal system includes a vacuum interface II, a feed inlet III, a feed and discharge vacuum tube and sealing seat III, a rotary sealing device III, a feed pipe II, a heating device II, a plasma chamber I, a plasma chamber II, a plasma chamber III, a plasma reactor, a magnetron III, an exhaust port and waste gas treatment interface III, a temperature controller III, an inert gas and flow meter interface II, and a reaction gas and flow meter interface II. The quality control and product collection and processing system includes vacuum interface III, feed inlet IV, cooling device, cooling chamber, vacuum packaging machine, and vacuum packaging barrel; The process auxiliary systems include power supply system, vacuum system, temperature control system, gas control system, cooling system, water production system, auxiliary material system, waste gas treatment system, waste liquid treatment system, waste solid treatment system, and monitoring system.

[0011] Preferably, the system includes an intelligent control center, controller I, controller II, controller III, controller IV, controller V, and controller VI, which are linked to the feeding system, hydrogenation targeted impurity removal system, acid leaching targeted impurity removal system, plasma targeted impurity removal system, quality control and product collection and processing system, and process auxiliary system, respectively; and equipped with temperature / pressure / time / composition composite sensors to achieve intelligent monitoring of the entire process.

[0012] Preferably, the power supply system, vacuum system, temperature control system, gas control system, cooling system, water production system, auxiliary material system, waste gas treatment system, waste liquid treatment system, and waste solid treatment system are respectively connected to the corresponding units, and the waste liquid / waste acid is recycled after being treated to meet the standards.

[0013] Preferably, the acid leaching targeted impurity removal system is equipped with a three-stage gradient reaction chamber to achieve segmented acid leaching, targeted impurity removal, microwave cleaning, and microwave drying, and is lined with an acid-resistant, high-temperature-resistant, pressure-resistant, and pollution-free material.

[0014] Preferably, all the inlet / outlet vacuum sealing seats and rotary sealing devices meet the high vacuum / high temperature / high pressure sealing requirements.

[0015] Preferably, the reactor, plasma reactor, and cooling tube are made of high-purity quartz tube; the silicon carbide tube has a hollow structure; and the microwave source is preferably 2.45 GHz.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This environmentally friendly process and equipment for the intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand used in semiconductors employs a three-stage targeted impurity removal system of hydrogenation synergistic acid leaching and plasma. It can purify 4N5 grade raw materials to 6N and above in one step, with single-element impurities below 0.1ppm. It accurately removes micro-nano inclusions and refractory lattice impurities, and the product fully meets the stringent purity requirements of high-end semiconductor manufacturing, effectively improving the insulation, heat resistance and service life of downstream chips and quartz devices.

[0017] This environmentally friendly process and equipment for the intelligent, continuous, targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand in semiconductor manufacturing enables clean production without fluorine, chlorine, or nitrate. It employs an environmentally friendly high-purity phosphoric acid system and is equipped with waste acid recycling, wastewater reuse, and tail gas treatment technologies. This fundamentally solves the problems of highly toxic pollution, equipment corrosion, and safety risks associated with traditional chlorination and hydrofluoric acid processes. At the same time, it saves energy and reduces consumption by more than 40%, possessing the advantages of environmentally friendly, safe, low-carbon, and sustainable industrial production.

[0018] This environmentally friendly process and equipment for the intelligent, continuous, targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand used in semiconductors achieves fully automated operation of the entire process, including feeding, impurity removal, cooling, testing, and packaging, through intelligent control and continuous production line design. Key parameters are precisely controlled, significantly improving production efficiency and batch stability, reducing raw material loss and labor costs, and enhancing the overall market competitiveness of domestically produced ultra-high purity quartz. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the device structure of the present invention; Figure 2 This is a schematic diagram of the method flow of the present invention; The attached diagram lists the components represented by each number as follows: 1-Furnace shell, 2-System intelligent control center, 3-Feeding system, 4-Bag, 5-Controller I, 6-Vacuum suction gun, 7-Vacuum double cone feeder, 8-Hydrogenation targeted impurity removal system, 9-Controller II, 10-Vacuum interface I, 11-Inlet I, 12-Inlet / outlet vacuum tube and sealing seat I, 13-Rotating sealing device I, 14-Inlet pipe I, 15-Heating device I, 16-Reaction chamber, 17-Reactor, 18-Silicon carbide tube I, 19-Basalt fiber layer I, 20-Stainless steel plate layer I, 21-Magnetron I, 22-Rotating sealing device II, 23-Inlet / outlet vacuum tube and sealing seat II, 24-Exhaust port and waste gas treatment interface I, 25-Temperature controller I, 26-Inert gas and flow meter interface I, 27 - Reaction gas and flow meter interface I, 28 - Discharge port I, 29 - Acid leaching targeted impurity removal system, 30 - Feed port II, 31 - Controller III, 32 - Exhaust port and waste gas treatment interface II, 33 - Pressure gauge I, 34 - Ultrapure water inlet, 35 - Temperature controller II, 36 - Timer, 37 - Auxiliary material inlet, 38 - Magnetron II, 39 - Stainless steel plate II, 40 - Lining, 41 - Reaction chamber waste liquid discharge channel, 42 - Gradient reaction circulation chamber, 43 - Multifunctional microwave rotating reaction chamber, 44 - Waste liquid discharge interface, 45 - Discharge port II, 46 - Reaction chamber I, 47 - Three-way valve I, 48 - Reaction chamber II, 49 - Three-way valve II, 50 - Reaction chamber III, 51 - Three-way valve III, 52 - Microwave cleaning and drying chamber, 53 - Plasma Targeted impurity removal system, 54-Controller IV, 55-Vacuum interface II, 56-Inlet III, 57-Inlet / outlet vacuum tube and sealing seat III, 58-Rotary sealing device III, 59-Inlet pipe II, 60-Heating device II, 61-Plasma chamber I, 62-Plasma chamber II, 63-Plasma chamber III, 64-Plasma control telescopic tube, 65-Plasma reactor, 66-Silicon carbide tube II, 67-Basalt fiber layer II, 68-Stainless steel plate III, 69-Magnetron III, 70-Rotary sealing device IV, 71-Inlet / outlet vacuum tube and sealing seat IV, 72-Exhaust port and waste gas treatment interface III, 73-Temperature controller III, 74-Inert gas and flow meter interface II, 75-Reaction gas and flow meter interface II, 76- 77 - Discharge port III; 78 - Quality control and product collection and processing system; 79 - Controller V; 80 - Vacuum interface III; 81 - Feed port IV; 82 - Rotary sealing device V; 83 - Feed pipe IV; 84 - Cooling device; 85 - Cooling pipe; 86 - Forced cooling pipe; 87 - Rotary sealing device VI; 88 - Inlet / outlet vacuum pipe and sealing seat V; 89 - Exhaust port and waste gas treatment interface IV; 90 - Temperature controller IV; 91 - Inert gas and flow meter interface III; 92 - Discharge port IV; 93 - Vacuum packaging machine; 94 - Vacuum interface IV; 95 - Vacuum packaging interface; 96 - Vacuum packaging barrel; 97 - Process auxiliary system; 98 - Controller VI; 99 - Power supply system; 100 - Vacuum system; 101 - Temperature control system.102-Gas Control System, 103-Cooling System, 104-Water Production System, 105-Auxiliary Material System, 106-Waste Gas Treatment System, 107-Waste Liquid Treatment System, 108-Waste Solids Treatment System, 109-Monitoring System. 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 1-2 An environmentally friendly process for the intelligent, continuous, targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors includes the following steps: Step 1: Material Preparation: After pretreatment, magnetic separation, flotation, and acid leaching, the high-purity quartz ore is loaded into the feed system silo for later use. Raw material requirements: SiO2 ≥ 3N, total impurities < 100 μg / g; Preferred: 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; particle size 0.1~0.3mm, purity ≥ 4N, qualified material purity reaches 4N5, total impurities < 50 μg / g; Step 2: The empty suction gun feeds the raw material into the vacuum double cone feeder at a feed / discharge speed of 0.2-2 kg / min; Step 3: Hydrogenation-Coordinated Acid Leaching Targeted Impurity Removal: Vacuum microwave hydrogenation removes lattice impurities, simultaneous microwave gradient acid leaching removes bursting micro / nano inclusions, and ultrapure water microwave cleaning and drying; Hydrogenation parameters: Ar / H2≥5N, mixed gas flow rate 10~100sccm, temperature 600~1200℃, time 30~240min, vacuum degree 0.1~0.01Pa; Acid leaching uses high-purity phosphoric acid gradient leaching: 20%~40%, 40%~60%, 60%~80%, liquid-solid ratio 2:1~5:1, pressure 2~10MPa, temperature 200~250℃, time 1~4h, ultrapure water resistivity ≥18.2MΩ・cm, drying temperature 200~250℃; Total impurities after removal <8ppm; Step 4: Plasma-targeted impurity removal: High-energy hydrogen mixed plasma is used for fine purification to remove residual nanoscale inclusions and lattice impurities; Parameters: Ar / H2≥6N, mixed gas flow rate 10~150sccm, vacuum degree 10⁻²~10⁻ 4Pa, temperature 600–1500℃, time 20–180 min; single element impurities <0.1 ppm; Step 5: Quality Control and Collection Processing: Vacuum cooling, testing, vacuum packaging and warehousing; cooling vacuum degree 0.1~0.01Pa, cooling medium ≥6NAr, flow rate 5~100cm³ / min, cooling rate 20~50℃ / min, cooling to 0~25℃; product purity ≥6N, single impurity <0.1ppm.

[0022] As a preferred embodiment of the present invention, the qualified raw material in step one has a particle size of 0.1-0.3 mm, a purity of 4N5, and a total impurity content of <50 μg / g.

[0023] As a preferred technical solution of the present invention, the cyclic parameters in step three enable stepwise targeted impurity removal, and the temperature, speed, and time control in step four enable fine purification of single particles.

[0024] As a preferred technical solution of the present invention, the entire process is completed in a Class 100 clean environment with humidity ≤40%, and the exhaust gas, wastewater, waste acid and waste residue are all treated to meet the standards. The waste acid is recycled and the wastewater is reused to produce ultrapure water.

[0025] Specifically, the above includes three stages and five steps: Phase 1: Material Preparation (1) Raw material pretreatment: The raw ore is crushed, graded, color sorted, magnetically separated, flotated and acid leached to obtain qualified material with 0.1-0.3mm, 4N5 and impurities <50μg / g, which is then sent to the silo; Phase Two: Three-Level Targeted Impurity Removal (2) Feeding: Vacuum suction, double cone uniform feeding, speed 0.2-2kg / min; (3) Hydrogenation and acid leaching: Vacuum microwave hydrogenation activation and removal of lattice impurities; high temperature causes the inclusions to burst, followed by gradient phosphoric acid microwave hot pressing leaching, ultrapure water washing and drying, and impurities reduced to <8ppm. (4) Plasma purification: High-energy hydrogen plasma precisely removes nanoscale inclusions and residual lattice impurities under high vacuum, with single impurity <0.1ppm and purity reaching 6N or higher; Phase 3: Post-processing (5) Vacuum cooling, online testing, vacuum packaging, and warehousing.

[0026] An environmentally friendly device for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors includes: a furnace shell 1, a feeding system 3, a hydrogenation targeted impurity removal system 8, an acid leaching targeted impurity removal system 29, a plasma targeted impurity removal system 53, a quality control and product collection and processing system 77, and a process auxiliary system 97. The feeding system includes: 3 (material hopper), 4 (vacuum suction gun), 6 (vacuum double cone feeder), and 7 (vacuum double cone feeder). Specifically, vacuum-sealed feeding is adopted to avoid contamination from contact between raw materials and air; the vacuum double cone feeder 7 achieves uniform, quantitative, and continuous feeding, ensuring stable flow matching between upstream and downstream processes, and a dust-free and sealed environment throughout the process to prevent secondary contamination; the feeding speed is precisely controllable (0.2-2kg / min), ensuring stable continuous production and improving batch consistency of products. The hydrogenation targeted impurity removal system 8 includes a vacuum interface I10, a feed inlet I11, a feed and discharge vacuum tube and sealing seat I12, a rotary sealing device I13, a feed pipe I14, a heating device I15, a reactor I7, a magnetron I21, a feed and discharge vacuum tube and sealing seat II23, an exhaust port and waste gas treatment interface I24, a temperature controller I25, an inert gas and flow meter interface I26, and a reaction gas and flow meter interface I27. Specifically, under high vacuum (0.01-0.1 Pa) and high temperature (600-1200℃) conditions, selective microwave heating is used. Hydrogen, as a reducing gas, reacts with lattice impurities to convert lattice impurities such as Al, Ti, Fe, and alkali metals into volatile substances. At the same time, the high temperature causes the micro-nano inclusions inside the quartz to burst, creating conditions for subsequent acid leaching. This directionally breaks the chemical bonds of lattice impurities, achieving preliminary deep removal of lattice impurities. The high-temperature bursting of micro-nano inclusions significantly improves the efficiency of subsequent acid leaching. It is chlorine-free and fluorine-free, making it environmentally friendly and safe. The acid leaching targeted impurity removal system 29 includes a feed inlet II 30, an exhaust port and waste gas treatment interface II 32, a pressure gauge I 33, an ultrapure water inlet 34, a temperature controller II 35, an auxiliary material inlet 37, a magnetron II 38, a gradient reaction circulation chamber 42, a multifunctional microwave rotating reaction chamber 43, a three-way valve I 47, a three-way valve II 49, a three-way valve III 51, a microwave cleaning and drying chamber 52, and a waste liquid discharge interface 44; Specifically, a three-stage gradient acid leaching process using high-purity phosphoric acid (20%-40%, 40%-60%, 60%-80%) is employed, under microwave heating, high pressure (2-10MPa), and medium temperature (200-250℃), to progressively leach out impurities from the burst inclusions and residual surface impurities. Subsequently, microwave cleaning and drying with 18.2MΩ·cm ultrapure water remove residual acid and soluble impurities, targeting and removing micro- and nano-sized inclusions. The total impurities after purification are <8ppm. Phosphoric acid is environmentally friendly and recyclable, avoiding corrosion and pollution from hydrofluoric acid. Microwave heating is uniform, preventing localized over-etching and protecting the integrity of the quartz crystal structure. The plasma targeted impurity removal system 53 includes a vacuum interface II 55, a feed inlet III 56, a feed and discharge vacuum tube and sealing seat III 57, a rotary sealing device III 58, a feed pipe II 59, a heating device II 60, a plasma chamber I 61, a plasma chamber II 62, a plasma chamber III 63, a plasma reactor 65, a magnetron III 69, an exhaust port and waste gas treatment interface III 72, a temperature controller III 73, an inert gas and flow meter interface II 74, and a reaction gas and flow meter interface II 75. Specifically, in ultra-high vacuum (10⁻²-10⁻²) 4 Under high temperatures (600-1500℃) and at Pa, high-energy hydrogen-mixed plasma is excited. Utilizing the high activity and high energy characteristics of plasma, single-particle quartz is finely etched and reduced to completely remove residual nanoscale inclusions and trace amounts of lattice impurities, achieving ultimate deep purification. Single-element impurities are <0.1ppm, and the quartz purity stably reaches 6N or higher. There are no chemical reagent residues, meeting the ultra-high cleanliness requirements for semiconductors. The quality control and product collection and processing system 77 includes a vacuum interface Ⅲ 79, a feed inlet Ⅳ 80, a cooling device 83, a cooling chamber 84, a vacuum packaging machine 93, and a vacuum packaging barrel 96. Specifically, high-purity argon gas is used for rapid cooling under high vacuum to avoid secondary oxidation and contamination of the high-temperature quartz; online quality inspection is conducted, and qualified products directly enter the vacuum packaging machine 93, where they are sealed and packaged in a high-purity atmosphere, and rapid cooling protects the quartz crystal structure; air is completely isolated throughout the process to prevent secondary adsorption of impurities; vacuum packaging ensures long-term quality and meets the storage and transportation standards for high-end semiconductor materials. The process auxiliary system 97 includes a power supply system 99, a vacuum system 100, a temperature control system 101, a gas control system 102, a cooling system 103, a water production system 104, an auxiliary material system 105, a waste gas treatment system 106, a waste liquid treatment system 107, a solid waste treatment system 108, and a monitoring system 109. Specifically, it provides stable vacuum, precise temperature, high-purity gas, ultrapure water, and auxiliary material supply for the entire process; it carries out harmless treatment of waste gas, waste liquid, and waste solid, reuses waste acid, and recycles wastewater to ensure long-term stability of parameters of each system; it ensures that the three wastes meet emission standards, has a high waste acid recycling rate, saves more than 40% of energy, and achieves green and environmentally friendly production.

[0027] As a preferred embodiment of the present invention, the system includes an intelligent control center 2, controller I 5, controller II 9, controller III 31, controller IV 54, controller V 78, and controller VI 98, which are respectively linked to the feeding system 3, the hydrogenation targeted impurity removal system 8, the acid leaching targeted impurity removal system 29, the plasma targeted impurity removal system 53, the quality control and product collection and processing system 77, and the process auxiliary system 97; equipped with temperature / pressure / time / composition composite sensors to achieve intelligent monitoring of the entire process. Specifically, the central control center provides unified scheduling, while the controllers of each subsystem independently execute parameter settings; sensors collect data in real time and automatically adjust key parameters such as feeding, temperature, vacuum, gas flow, and acid leaching time, enabling fully automated and intelligent operation and 24-hour uninterrupted production; precise parameter control ensures high product consistency and significantly reduces labor costs and operational errors.

[0028] As a preferred technical solution of the present invention, the power supply system 99, vacuum system 100, temperature control system 101, gas control system 102, cooling system 103, water production system 104, auxiliary material system 105, waste gas treatment system 106, waste liquid treatment system 107, and waste solid treatment system 108 are respectively connected to the corresponding units, and the waste liquid / waste acid is recycled after reaching the standard.

[0029] As a preferred technical solution of the present invention, the acid leaching targeted impurity removal system 29 is provided with a three-level gradient reaction chamber to realize segmented acid leaching, targeted impurity removal, microwave cleaning and microwave drying, and is lined with an acid-resistant, high-temperature-resistant, pressure-resistant and pollution-free material.

[0030] As a preferred embodiment of the present invention, all the infeed / outfeed vacuum sealing seats and rotating sealing devices meet the requirements for high vacuum / high temperature / high pressure sealing.

[0031] As a preferred embodiment of the present invention, the reactor 17, the plasma reactor 65, and the cooling tube are made of high-purity quartz tubes; the silicon carbide tube has a hollow structure; and the microwave source is preferably 2.45 GHz.

[0032] Example 1 (Low load mode: 0.35 kg / min) Preparation: Raw material - 4N5, 0.1-0.3mm, impurities <50μg / g; Feeding rate: 0.35 kg / min; Hydrogenation: 1000℃, 0.01Pa, mixed gas -60sccm, 40min; Acid leaching: Phosphoric acid - 30% / 50% / 70%, 5MPa, 200℃, 40min per stage, followed by rinsing and drying; Plasma: 1000℃, 10⁻³Pa, mixed gas -80sccm, 40min; Cooling: Ar flow rate -20cm³ / min, cool to -25℃, vacuum packaged; Product: Purity -6N, single impurity <0.1ppm.

[0033] Example 2 (Medium load mode: 0.70 kg / min) Preparation of materials: Same as in Example 1; Feeding rate: 0.70 kg / min; Hydrogenation: 1100℃, 0.01Pa, mixed gas -80sccm, 50min; Acid leaching: Phosphoric acid - 30% / 50% / 70%, 6MPa, 200℃, 50min per stage; Plasma: 1100℃, 10⁻³Pa, mixed gas -100sccm, 50min; Cooling: Ar flow rate - 30 cm³ / min; Product: Purity -6N, meets the standard.

[0034] Example 3 (High load mode: 1.05 kg / min) Preparation of materials: Same as in Example 1; Feeding rate: 1.05 kg / min; Hydrogenation: 1200℃, 0.01Pa, mixed gas -100sccm, 60min; Acid leaching: Phosphoric acid - 40% / 60% / 80%, 7MPa, 200℃, 60min per stage; Plasma: 1200℃, 10⁻³Pa, mixed gas -120sccm, 60min; Cooling: Ar flow rate - 40 cm³ / min; Product: Purity -6N+, meeting the requirements of high-end semiconductors.

[0035] 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 process for the intelligent, continuous, targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors, characterized in that, Includes the following steps: Step 1: Material Preparation: After soaking, washing, crushing and grading, color sorting, magnetic separation, flotation, and acid leaching, the high-purity quartz ore is loaded into the feed system silo for later use; Raw material requirements: SiO2 ≥ 3N, total impurities < 100 μg / g; Preferred: 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; Particle size 0.1~0.3mm, purity ≥ 4N, qualified material purity reaches 4N5, total impurities < 50 μg / g; Step 2: The vacuum suction gun feeds the raw material into the vacuum double cone feeder at a feed / discharge speed of 0.2-2 kg / min; Step 3: Hydrogenation-Coordinated Acid Leaching Targeted Impurity Removal: Vacuum microwave hydrogenation removes lattice impurities, simultaneous microwave gradient acid leaching removes bursting micro / nano inclusions, and ultrapure water microwave cleaning and drying; Hydrogenation parameters: Ar / H2≥5N, mixed gas flow rate 10~100sccm, temperature 600~1200℃, time 30~240min, vacuum degree 0.1~0.01Pa; Acid leaching uses high-purity phosphoric acid gradient leaching: 20%~40%, 40%~60%, 60%~80%, liquid-solid ratio 2:1~5:1, pressure 2~10MPa, temperature 200~250℃, time 1~4h, ultrapure water resistivity ≥18.2MΩ・cm, drying temperature 200~250℃; Total impurities after removal <8ppm; Step 4: Plasma-targeted impurity removal: High-energy hydrogen mixed plasma is used for fine purification to remove residual nanoscale inclusions and lattice impurities; Parameters: Ar / H2≥6N, mixed gas flow rate 10~150sccm, vacuum degree 10⁻²~10⁻ 4 Pa, temperature 600–1500℃, time 20–180 min; single element impurities <0.1 ppm; Step 5: Quality Control and Collection Processing: Vacuum cooling, testing, vacuum packaging and warehousing; cooling vacuum degree 0.1~0.01Pa, cooling medium ≥6NAr, flow rate 5~100cm³ / min, cooling rate 20~50℃ / min, cooling to 0~25℃; product purity ≥6N, single impurity <0.1ppm.

2. The environmentally friendly process for intelligent continuous targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors according to claim 1, characterized in that: In step one, the qualified raw material has a particle size of 0.1-0.3 mm, a purity of 4N5, and a total impurity content of <50 μg / g.

3. The environmentally friendly process for intelligent continuous targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors according to claim 1, characterized in that: In step three, the cyclic parameters enable stepwise targeted impurity removal, and in step four, temperature control, speed control, and time control are used to achieve fine purification of single particles.

4. The environmentally friendly process for intelligent continuous targeted removal of inclusions and lattice impurities using ultra-high purity quartz sand for semiconductors according to claim 1, characterized in that: The entire process is completed in a Class 100 cleanroom environment with humidity ≤40%. The exhaust gas, wastewater, waste acid, and waste residue are all treated to meet standards. Waste acid is recycled and wastewater is reused to produce ultrapure water.

5. An environmentally friendly device for intelligent, continuous, targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand used in semiconductors, characterized in that, include: Furnace shell (1), feeding system (3), hydrogenation targeted impurity removal system (8), acid leaching targeted impurity removal system (29), plasma targeted impurity removal system (53), quality control and product collection and processing system (77), process auxiliary system (97). The feeding system (3) includes a hopper (4), a vacuum suction gun (6), and a vacuum double cone feeder (7); The hydrogenation targeted impurity removal system (8) includes a vacuum interface I (10), a feed inlet I (11), a feed inlet and outlet vacuum tube and sealing seat I (12), a rotary sealing device I (13), a feed pipe I (14), a heating device I (15), a reactor (17), a magnetron I (21), a feed inlet and outlet vacuum tube and sealing seat II (23), an exhaust port and waste gas treatment interface I (24), a temperature controller I (25), an inert gas and flow meter interface I (26), and a reaction gas and flow meter interface I (27). The acid leaching targeted impurity removal system (29) includes feed inlet II (30), exhaust port and waste gas treatment interface II (32), pressure gauge I (33), ultrapure water inlet (34), temperature controller II (35), auxiliary material inlet (37), magnetron II (38), gradient reaction circulation chamber (42), multifunctional microwave rotating reaction chamber (43), three-way valve I (47), three-way valve II (49), three-way valve III (51), microwave cleaning and drying chamber (52), and waste liquid discharge interface (44); The plasma targeted impurity removal system (53) includes a vacuum interface II (55), a feed inlet III (56), a feed and discharge vacuum tube and sealing seat III (57), a rotary sealing device III (58), a feed pipe II (59), a heating device II (60), a plasma chamber I (61), a plasma chamber II (62), a plasma chamber III (63), a plasma reactor (65), a magnetron III (69), an exhaust port and waste gas treatment interface III (72), a temperature controller III (73), an inert gas and flow meter interface II (74), and a reaction gas and flow meter interface II (75). The quality control and product collection and processing system (77) includes vacuum interface III (79), feed port IV (80), cooling device (83), cooling chamber (84), vacuum packaging machine (93), and vacuum packaging barrel (96); The process auxiliary system (97) includes a power supply system (99), a vacuum system (100), a temperature control system (101), a gas control system (102), a cooling system (103), a water production system (104), an auxiliary material system (105), a waste gas treatment system (106), a waste liquid treatment system (107), a waste solid treatment system (108), and a monitoring system (109).

6. The environmentally friendly equipment for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors according to claim 5, characterized in that: The system is equipped with an intelligent control center (2), controller I (5), controller II (9), controller III (31), controller IV (54), controller V (78), and controller VI (98), which are linked to the feeding system (3), hydrogenation targeted impurity removal system (8), acid leaching targeted impurity removal system (29), plasma targeted impurity removal system (53), quality control and product collection and processing system (77), and process auxiliary system (97), respectively; and equipped with temperature / pressure / time / composition composite sensors to realize intelligent monitoring of the entire process.

7. The environmentally friendly equipment for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors according to claim 5, characterized in that: The power supply system (99), vacuum system (100), temperature control system (101), gas control system (102), cooling system (103), water production system (104), auxiliary material system (105), waste gas treatment system (106), waste liquid treatment system (107), and waste solid treatment system (108) are respectively connected to the corresponding units, and the waste liquid / waste acid is recycled after reaching the standard.

8. The environmentally friendly equipment for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors according to claim 5, characterized in that: The acid leaching targeted impurity removal system (29) is equipped with a three-level gradient reaction chamber to realize segmented acid leaching, targeted impurity removal, microwave cleaning, and microwave drying. The inner lining is made of acid-resistant, high-temperature-resistant, pressure-resistant, and pollution-free material.

9. An environmentally friendly device for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors according to claim 5, characterized in that: All the inlet and outlet vacuum sealing seats and rotary sealing devices meet the high vacuum / high temperature / high pressure sealing requirements.

10. An environmentally friendly device for intelligent continuous targeted removal of inclusions and lattice impurities from ultra-high purity quartz sand for semiconductors according to claim 5, characterized in that: The reactor (17), plasma reactor (65), and cooling tube are made of high-purity quartz tube; the silicon carbide tube has a hollow structure; and the microwave source is preferably 2.45 GHz.

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