A method and device for regulating ultra-pure water used in a stable output semiconductor process

Abstract

A kind of regulating method and device for stabilizing output ultra-pure water for semiconductor process, the regulating method includes: S1 deep processing: to the secondary pure water of once pure water treatment;S2 first-order circulation: part of secondary pure water is backflowed and circulated to step S1, and the secondary pure water that is not backflowed is stored in pure water storage tank, according to the analog output result of pure water storage tank liquid level, proportionally distribute backflow water volume, form first-order circulation ratio, according to the detection result of secondary pure water and first-order circulation ratio, regulate the target decomposition dose of first-order decomposition treatment;S3 fine processing: to the ultra-pure water of secondary pure water treatment;S4 second-order circulation: according to the water quantity of downstream semiconductor process, output ultra-pure water stably, and the remaining ultra-pure water is backflowed and circulated to step S3, while according to the detection result of process ultra-pure water and ultra-pure water, regulate the target decomposition dose of second-order decomposition treatment.The present application can output quality and flow stable ultra-pure water according to downstream semiconductor process water demand, efficiently and with low energy consumption.

Description

Technical Field

[0001] This invention relates to the field of ultrapure water technology for semiconductor processes, and more particularly to a method and apparatus for regulating the stable output of ultrapure water for semiconductor processes. Background Technology

[0002] With the development of the electronics industry, the requirements for water quality in chip manufacturing are becoming increasingly stringent. For the production of very large-scale integrated circuits, in addition to high-purity raw materials, high-purity gases, and high-purity chemicals, ultrapure water is also a key factor. Ultrapure water is mainly used in semiconductor manufacturing processes for product cleaning and chemical dilution. The ultrapure water manufacturing process mainly consists of three stages: pretreatment, primary pure water treatment, and ultrapure water treatment. In recent years, with the shrinking of semiconductor device manufacturing processes, extremely high requirements have been placed on the water used in production processes for indicators such as trace metals, total organic carbon (TOC), total silicon, microparticles, and dissolved oxygen (DO). Currently, much of the technological research focuses on the design and engineering assurance of various water treatment processes, aiming to develop advanced ultrapure water preparation processes to meet the water quality requirements of semiconductor advanced manufacturing processes and achieve the combined removal of multiple pollutants, thereby achieving comprehensive control of indicators such as trace metals, TOC, boron (B), DO, and H2O2. However, little attention is paid to the stable production of ultrapure water from ultrapure water preparation processes and its coordination with downstream semiconductor process water. Even less attention is paid to rationally adjusting the treatment time, intensity, and circulation mode of each treatment stage based on the quality requirements of downstream semiconductor process water and the detection data of each treatment stage, resulting in energy waste in some treatment stages and high production costs.

[0003] Invention CN114751539A discloses a process for preparing ultrapure water that improves process stability and water quality. The process includes: a PLC system controlling the electric proportional valves and pumps in the first-stage reverse osmosis system; the PLC system monitoring the SDI value of the ultrafiltration effluent and the pressure difference of the permeate in the UF ultrafiltration system; backwashing when the SDI rises to a certain value; and chemical cleaning when the pressure difference of the permeate reaches a certain value; monitoring the pH value of the raw water entering the MB regeneration mixed bed and adjusting the influent pH value; monitoring the inlet and outlet resistance values ​​of the TOC (Total Organic Carbon) and dynamically adjusting the number of polishing resin tanks; and monitoring the system's water temperature difference variation to be less than 5°C. This ultrapure water process can improve the permeate water stability of the ultrapure water system, reduce process wastewater discharge, increase the system's permeate water rate, and meet the semiconductor industry's more stable, reliable, and stringent water quality requirements for ultrapure water systems. However, while the invention can improve the stability of water quality and production volume by using monitoring and backwashing systems, it does not take into account changes in water consumption and quality requirements of downstream semiconductor processes. It is difficult to quickly adjust the output of high-quality and stable ultrapure water, which can easily lead to insufficient downstream water use, water waste, or mismatch in water quality.

[0004] Invention CN118545861A discloses an intelligent control system and method for ultrapure water quality. The system includes a multi-stage filtration unit, a reverse osmosis treatment unit, an electro-deionization purification unit, and an ultrapure water tank. The outlet of the ultrapure water tank is connected to at least one water supply pipe. It also includes a control unit, a rating unit, and at least one monitoring unit. Each monitoring unit corresponds to one water supply pipe and is used to monitor the water quality data of the pure water in the supply pipe in real time and send it to the rating unit. The rating unit receives the water quality data, performs integrated calculations and management, rates the water quality according to preset levels, and sends the data to the control unit. The control unit executes a return water procedure or a water supply procedure corresponding to the rating result. This invention monitors the pure water quality stored in the ultrapure water tank in real time and rates it to allow for targeted return purification based on different rating results, thereby improving purification efficiency, ultrapure water quality stability, and reducing losses in each purification unit. However, the ultrapure water stored in the tank for a long time becomes increasingly contaminated, and return water purification will significantly increase energy consumption.

[0005] Therefore, how to design and improve existing ultrapure water preparation processes, and combine them with modern monitoring, detection and automated control methods to achieve scientific prediction and comprehensive control of water quality indicators, provide a continuous and stable supply of ultrapure water, improve water resource utilization, and reduce energy consumption and operating costs has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] To address the deficiencies in the existing technologies, this invention provides a method and apparatus for regulating the stable output of ultrapure water for semiconductor processes. This method enables the estimation, prediction, and comprehensive control of indicators such as trace metals, TOC, boron (B), DO, and H2O2, continuously providing high-quality ultrapure water and ensuring a controllable and stable output to meet the water needs of downstream semiconductor processes, improving water resource utilization, and effectively reducing energy consumption and operating costs.

[0007] In a first aspect, the present invention provides a method for regulating the stable output of ultrapure water for semiconductor processes, comprising the following steps: S1 Deep Treatment: Deep desalination, first-stage decomposition, first-stage absorption and exchange, and degassing treatment are performed on primary pure water to obtain secondary pure water. S2 First-order cycle: Part of the secondary pure water obtained in step S1 is returned to the deep processing step S1, and the secondary pure water that is not returned is stored in the pure water storage tank. S3 Fine Treatment: The secondary pure water output from the pure water storage tank is hydrogenated to make the dissolved hydrogen concentration above 0.05 mg / L. Then, it undergoes second-stage decomposition treatment, second-stage absorption and exchange treatment, degassing and ultrafiltration treatment to obtain ultrapure water. S4 Second-order cycle: Based on the water consumption of downstream semiconductor processes, output ultrapure water stably, and return the remaining ultrapure water to step S3 for fine treatment.

[0008] This invention achieves a stable and reliable supply of ultrapure water that meets the requirements of semiconductor processes through a combination of multi-stage purification and circulation control. Multi-stage purification ensures maximum removal of impurities, while circulation control guarantees the continuous stability of water quality and output volume. Furthermore, by controlling the degree of purification and the circulation ratio, an optimal balance is achieved between water purity and output efficiency.

[0009] Specifically, the raw water is pretreated to obtain primary pure water (conductivity < 2 μS / cm, TOC < 50 μg / L). The series of treatments of the raw water can refer to the method provided in the previous invention patent CN115636557B, or other methods that can obtain primary pure water can be used.

[0010] Preferably, the first-order decomposition process and the second-order decomposition process are performed using several independently controlled ultraviolet radiation sources. The target decomposition dose for first-order decomposition treatment is 100-800 mJ / cm³. 2 Continuously adjustable; The target decomposition dose for the second-order decomposition treatment is 200-1000 mJ / cm³. 2 Continuously adjustable.

[0011] Preferably, the radiation source for the first-order decomposition process and the second-order decomposition process includes VUV / UV low-pressure high-intensity mercury vapor or low-pressure high-intensity mercury alloy arc discharge source.

[0012] The specific number is determined based on the volume and quality requirements of the water to be treated. When the water production demand is low, 1-5 radiation light sources can be set. Typically, 5-50 radiation light sources can be set to meet the needs of most application scenarios. The operating current and irradiation duration of each radiation light source are independently adjustable, thereby controlling the overall ultraviolet target decomposition dose. More preferably, multiple radiation light sources are grouped, connected, and controlled, for example, into 2-10 groups, with approximately 1-8 radiation light sources in each group, making the radiation light sources easier to control. Through the optimized design of the radiation light sources in this invention, the current, output power, and energy consumption can be reduced according to the actual water volume and quality requirements. On the other hand, the water usage in downstream semiconductor processes is usually relatively stable, and frequent switching on and off of the radiation light sources is not recommended as it can easily reduce the lifespan of the light sources. Therefore, it is further preferred to control the variable current output of the ballast to reduce the current intensity and power output, thereby extending the lifespan of the radiation light sources while saving energy and reducing overall production costs.

[0013] Preferably, the first-order absorption exchange treatment includes positive charge adsorption treatment, complexation reaction treatment and ion polishing treatment in sequence, and the ratio of the treatment time of positive charge adsorption treatment, complexation reaction treatment and ion polishing treatment is (1-4):(1-12):(1-6). The second-order absorption-exchange treatment includes catalytic decomposition treatment and ion polishing treatment in sequence, with the treatment time ratio of catalytic decomposition treatment to ion polishing treatment being 1:(1-50).

[0014] Based on the characteristics of water flow, the duration of each of the above-mentioned treatment stages is related to the thickness and amount of the treatment material that the water flows through. The present invention sets the above-mentioned treatment time ratio based on the material usage of each treatment zone of absorption and exchange configured through multiple experiments, which can better meet the treatment effect.

[0015] The purified water undergoes a continuous electro-desalination system or ion exchange system to deeply remove anions and cations, and a small amount of TOC. It then undergoes the aforementioned first-stage decomposition treatment, followed by downstream first-stage absorption-exchange treatment (positive charge adsorption, complexation reaction, and ion polishing). This process decomposes low-molecular-weight organic matter (LMWOM), removes weakly ionized impurities, and lowers resistivity without contamination. Specifically, the positive charge adsorption treatment uses a positively charged adsorbent to efficiently adsorb low-molecular-weight acidic organic matter (LMW CAs) generated by 185nm UV oxidation of LMWOM. The complexation reaction treatment uses a boron absorbent to achieve deep boron removal through a complexation reaction. The ion polishing treatment uses an ion exchanger to remove micro-polluting electrolytes released by NMDG-based absorbents, inhibiting the decrease in resistivity and controlling the increased TOC concentration to 1 μg / L or even lower, comprehensively improving the quality of the permeate from the first-stage absorption-exchange treatment. Finally, degassing removes dissolved oxygen (including dissolved gases and volatile substances) from the water and resin, forming secondary purified water.

[0016] The secondary purified water in the pure water storage tank meets the following water quality requirements: resistivity > 18.1 MΩ·cm, TOC < 5 μg / l, B < 5 ng / l, DO < 5 μg / l; preferably, resistivity > 18.2 MΩ·cm, TOC < 3 μg / l, B < 3 ng / l, DO < 2 μg / l.

[0017] The secondary purification process first involves dissolving high-purity H2 in a membrane gas absorber (MGA) to achieve a dissolved hydrogen concentration above 0.05 mg / L. Then, following the aforementioned two-stage decomposition treatment, and downstream of this decomposition treatment, a two-stage absorption-exchange treatment (catalytic decomposition and ion polishing) further removes, absorbs, and decomposes trace metal ions, dissolved oxygen, weakly ionized impurities, and low-molecular-weight organic matter, reducing them to extremely low limits at the ppq, ppt, and ppb levels, respectively. Simultaneously, under the action of nano-multiphase catalysis, the H2O2 generated during the photo-oxidation of TOC can be controlled to sub-ppb levels (below 1 μg / L). Specifically, a metal catalyst is used in the catalytic decomposition process, preferably a supported metal catalyst. The supported metal catalyst matrix can be a positively charged adsorbent capable of efficiently adsorbing low-molecular-weight acidic organic compounds (LMW CAs) generated by 185nm UV oxidation of organic matter. Simultaneously, it can decompose the photo-oxidation byproduct H2O2, ensuring H2O2 < 1 μg / L. Furthermore, under the action of an appropriate amount of H2, it can catalytically reduce the byproduct O2 of the decomposition reaction to H2O at the active sites on the catalyst surface. Subsequently, the ion exchanger used in the ion polishing process further removes trace metals and increases resistivity. Finally, degassing and ultrafiltration processes achieve deep removal of dissolved gases and microparticles.

[0018] After the above series of treatments, the output ultrapure water quality can stably reach: Trace metals < 0.1 ng / l, TOC < 0.5 μg / l, DO < 1 μg / l, B < 1 ng / l, H2O2 < 1 μg / l, and particle number concentration greater than 0.05 μm < 0.1 pcs / mL.

[0019] Preferably, the positive charge adsorption treatment uses a positive charge adsorbent, which is a positive charge adsorption resin with amine polyhydroxy functional groups or a mixed resin containing positive charge adsorption resin with amine polyhydroxy functional groups. One method of preparing this adsorbent is to prepare it by suspension polymerization, chloromethylation and amination reaction of dimethylbenzene, trimethylamine and other main raw materials on a chloromethylated polystyrene cross-linked microsphere skeleton. More preferably, a trimethylbenzylammonium gel-type divinylbenzene cross-linked adsorbent or a mixed resin containing this adsorbent is selected, which has a stronger adsorption function for anionic electrolytes in water, especially small molecule organic matter. Even more preferably, a high-purity grade of this type of adsorbent is selected to ensure and meet the special requirement of ΔTOC≤1μg / l.

[0020] The complexation reaction treatment uses a boron absorbent, which is a monodisperse porous absorbent, including meglumine-based granular beads or chelating resins. The boron absorbent can be prepared by grafting aliphatic polyols or aromatic polyhydroxyphenols onto a polymer backbone. Preferably, to overcome the limitations of porous hydrophobic polymer backbones being difficult to wet and affecting mass transfer, and the defects of the crosslinking agent divinylbenzene in the backbone containing multiple isomers that significantly affect the polymer structure and properties, polyglycerol methacrylate (GMA, chemical formula C7H4) with strong hydrophilicity and increased average pore size after grafting is used. 10 O3) and ethylene glycol dimethacrylate (EDM, chemical formula C 10 H 14 Using a macroporous copolymer formed from O4 as the backbone matrix, NMDG is grafted onto the macroporous particle backbone of the copolymer dissolved in dimethyl sulfoxide solution to prepare the high-efficiency boron absorbent GMA-EDM-NMDG. More preferably, a mixture of dimethylformamide and deionized water is used to enhance resin swelling to improve pore size and functional group density, and a porous chloromethyl polystyrene crosslinked resin (CMPS) with better structure and mechanical properties after crosslinking provides more active sites for adsorption is used as the polymer backbone carrier. Similarly, a polyol containing more extended polyhydroxy aliphatic long carbon chain polyol is used as the functional monomer. A one-step adsorption method is used, involving stirring, washing, and drying, to obtain a monodisperse porous resin boron absorbent containing ortho- and meta-dihydroxy functional groups.

[0021] The catalytic decomposition process employs a metal catalyst, preferably a supported metal nanoparticle catalyst, which is a multiphase metal catalyst in which a transition metal is used as a complex to directly bond with the copolymer backbone of styrene, acrylic acid, etc., to form a polymeric complex. More preferably, noble metal nanoparticles such as Pd or Pt are dispersed on the surface of a dimethylhydroxyethyl benzyl ammonium polymer support phase to prepare UP-grade palladium-supported resin or platinum-supported resin. Furthermore, a polystyrene-divinylbenzene crosslinked polymer is functionalized with trimethylamine quaternary ammonium groups as a solid support, and a static adsorption method and a one-step reduction method are used, utilizing coordination covalent bonds. Heterogeneous gel-type or macroporous resin-based catalysts are obtained by complexing heterogeneous platinum group metal (palladium, platinum, ruthenium, rhodium, osmium, iridium) ionic precursors and reducing them. Typical examples include gel-type polystyrene-supported palladium metal nanoparticle catalysts. Alternatively, amino-functionalized PS microspheres can be used as polymer supports. A heterogeneous condensation method based on thermodynamic principles can be applied, using a liquid bimetallic solution as a precursor salt. Stabilizers and reducing agents are added to synthesize a nanoparticle dispersion, which is then mixed, stirred, filtered, and dried with the PS microsphere dispersion to obtain a nano-alloy composite particle catalyst.

[0022] Ion polishing treatment uses two ion exchangers that are pre-mixed in a certain proportion and respectively contain basic and acidic groups. Preferred is a non-regenerative high-purity mixed ion exchanger with a TOC leaching amount ≤1μg / l and a metal leaching amount ≤0.1ng / l.

[0023] Specifically, the first-order and second-order decomposition processes utilize ultraviolet light from UV lamps for decomposition. The target decomposition dose can be predicted and dynamically controlled using a kinetic model. The construction method of the molecular dynamics calculation model (VUV Dosing CalcEM) includes: when molecules absorb ultraviolet radiation, they gain energy, and the amount of absorbed energy is related to the incident wavelength. According to Einstein's law, the photon energy absorbed by 1 mol of TOC molecules is shown in Equation 1 (unit: eV). The required ultraviolet dose depends on the ultraviolet intensity and exposure time, as shown in Equation 2. The core of the reaction is the hydroxyl radical (OH·), which, when homolytically cleaved by 185nm ultraviolet light irradiating water flow, generates OH· that can oxidize organic matter into carbon dioxide, water, and intermediate products (Equations 3 and 4).

[0024] (Equation 1) (Equation 2) (Equation 3) (Equation 4) Where E is the photon energy, h is Planck's constant, c is the speed of light, λ is the radiation wavelength, D is the target decomposition dose of ultraviolet radiation, I is the radiation intensity, and t is the radiation time.

[0025] Based on the mass balance at the mixing point and the equality of mass flow input and output, the volume of the decomposition reaction zone for first-order decomposition treatment can be obtained using the first-order rate equation. Through (Equation 5), the amount of micro-pollutants in primary pure water can be further determined. and first-order cycle ratio R m After first-order decomposition and first-order absorption-exchange treatments, the target decomposition dose D of the first-order decomposition treatment is adjusted. pm The amount of micro-pollutants in the secondary pure water was obtained. See (Equation 6) for the amount of micro-pollutants in secondary pure water. The calculation process is as follows: (Equation 5) (Equation 6) Among them, R m R is the first-order cycle ratio. m It ranges from 0.1 to 10. Q mr To reflux the secondary pure water volume, Q me The amount of secondary pure water stored in the pure water storage tank; The volume of the decomposition reaction zone for the first-order decomposition treatment. RE mdi To improve the decomposition efficiency of deep desalination treatment, TOC me This refers to the amount of trace pollutants in the secondary purified water. TOC mi This refers to the amount of micro-contaminants in a single batch of pure water. R m The cycle ratio for first-order processing. K m1 K m2 The reaction rate constant is... For example, when R m When the concentration is 0.1, the amount of micro-pollutants after mixing primary pure water with secondary pure water from the first-stage circulation return stream is... :

[0026] Based on the above calculations, the present invention can achieve the target decomposition dose D through first-order decomposition processing. pm The first-order processing cycle ratio R m Based on factors such as these, the amount of micro-pollutants in secondary pure water can be predicted or preset. .

[0027] Considering pipeline characteristics, and based on the mass balance at the mixing point of the pure water storage tank and the equality of input and output mass flow rates, the volume of the decomposition reaction zone for the second-order decomposition process can be obtained using the first-order rate equation. See (Equation 7). The amount of micro-pollutants in ultrapure water can be obtained through dosage calculation formulas and related calculations. See (Equation 8) for the amount of micro-pollutants in ultrapure water. The calculation process is as follows:

[0028] (Equation 7) (Equation 8) Among them, R p R is the second-order cyclic ratio. p Between 0.2 and 0.8, Q pr To reflux ultrapure water volume, Q pe This indicates the amount of ultrapure water used in downstream semiconductor processes. D pe The target decomposition dose for the second-order decomposition process. TOC pe For ultrapure water with minimal contamination, The ultrapure water reflux is used to observe the concentration gradient of micro-contaminant leaching; v is the second-order decomposition treatment rate; K t K is the time constant. p1 K p2 K p3 The reaction rate constant is... λ is the characteristic coefficient of the pipeline network, which satisfies equation (9): (Equation 9) L represents the length of the pipeline network. There are several options for the connection location of the return water pipe. It can be set at the outlet of the membrane microparticle separator or downstream along the water supply network, for example, near the ultrapure water usage point, so as to supply water to the semiconductor process water usage point more stably and accurately. Therefore, L preferably includes the total length of the water supply network and the return water network. Due to the precipitation factor of the pipe material, the amount of micro-contamination in the return water flowing back to the pure water storage tank in the second-order circulation will be slightly higher than the amount of micro-contamination in the ultrapure water supplied to the downstream semiconductor process. This invention summarizes the experimental data of this factor and thus introduces the pipeline network characteristic coefficient λ, which is beneficial to improve the accuracy of actual calculation.

[0029] Under normal circumstances, the second-order circulation ratio is not significantly adjusted, but the pipe network flow velocity will change because the flow rate fluctuates with the water consumption. If the pipe diameter remains unchanged, the pipe flow velocity will change accordingly. In practice, the second-order decomposition treatment rate v is also equivalent to the pipe flow velocity.

[0030] Through the aforementioned deep treatment, first-stage circulation, fine treatment, and second-stage circulation, this invention can stably provide ultrapure water that simultaneously meets the following water quality conditions over a long period: Trace metals < 0.1 ng / l, TOC < 0.5 μg / l, DO < 1 μg / l, B < 1 ng / l, H2O2 < 1 μg / l, and particle number concentration greater than 0.05 μm < 0.1 pcs / mL.

[0031] Secondly, the present invention also provides an apparatus for operating the control method, comprising a circulating deep treatment system, a pure water storage tank, and a circulating fine treatment system connected in sequence; The circulating deep treatment system includes a deep desalination device, a first-stage mixed photolysis absorber, and a membrane degasser. The outlet of the membrane degasser is connected to the pure water storage tank and the inlet of the deep desalination device in a controlled manner. The circulating fine treatment system includes a membrane absorber, a second-stage mixed photolysis absorber, a membrane degasser, and a membrane microparticle separator. The outlet of the membrane microparticle separator is connected to the ultrapure water point and the pure water storage tank in a controlled manner. The first-order hybrid photolysis absorber is compatible with the first-order decomposition region and its downstream first-order absorption-exchange region; the second-order hybrid photolysis absorber is compatible with the second-order decomposition region and its downstream second-order absorption-exchange region. The membrane absorber includes a hydrogen-dissolving membrane and a hydrogen supply line, providing hydrogen-filled water with a dissolved hydrogen concentration of 0.05 mg / L or higher to the downstream second-stage mixed photolysis absorber.

[0032] A first-order hybrid photolysis absorber compatible with the first-order decomposition region and its downstream first-order absorption-exchange region, and a second-order hybrid photolysis absorber compatible with the second-order decomposition region and its downstream second-order absorption-exchange region, their basic structures can be found in patent CN115636557B. The main differences are the order and processing time of each functional processing region in the first-order absorption-exchange region and the second-order absorption-exchange region, as well as the improved functions of grouping and controlling the radiation source in the first-order decomposition region and the second-order decomposition region.

[0033] Preferably, the deep desalination equipment includes at least one of a continuous electro-desalination device, a mixed ion exchange tower, and a composite ion exchange tower.

[0034] Preferably, it also includes a control unit and an online detection unit; The detection unit includes a level detector installed in the pure water storage tank, and sampling points installed at the inlet of the deep desalination equipment, the outlet of the membrane degasser and the membrane microparticle separator, as well as detection equipment connected to the sampling points. The control unit is connected to the level detector, the first distribution actuator, and the second distribution actuator. Based on the feedback value from the level detector, the first distribution actuator is driven to distribute the return water volume of the secondary pure water at a proportional opening, forming a first-order circulation ratio. Based on the amount of ultrapure water used in the process, the second distribution actuator is driven to distribute the return water volume of the ultrapure water at a proportional opening, forming a second-order circulation ratio.

[0035] Preferably, in the direction of water flow, the first-order absorption and exchange region includes a stacked positively charged adsorption layer, a complexation reaction layer, and an ion polishing layer, and the second-order absorption and exchange region includes a stacked catalytic decomposition layer and an ion polishing layer. The control unit adjusts the target decomposition dose in the first-order decomposition zone and / or the target decomposition dose in the second-order decomposition zone based on the feedback results from the detection equipment.

[0036] The detection equipment includes at least one of a TOC analyzer, a dissolved oxygen analyzer, a particulate matter analyzer, and a boron concentration analyzer. Preferably, the control unit adjusts the target decomposition dose in the first-stage decomposition zone and the target decomposition dose in the second-stage decomposition zone based on the feedback results from the detection equipment. Specifically, the target decomposition dose of the first-stage decomposition treatment is adjusted based on the amount of micro-contamination in the primary pure water and the first-stage circulation ratio to control the amount of micro-contamination in the secondary pure water. Furthermore, the target decomposition dose of the second-stage decomposition treatment is adjusted based on the amount of micro-contamination in the secondary pure water and the second-stage circulation ratio to control the amount of micro-contamination in the ultrapure water. This allows for the control of the quality and quantity of output ultrapure water with lower processing energy consumption, for example, by predicting and dynamically adjusting the ultraviolet target decomposition metering in the first-stage and second-stage decomposition treatments.

[0037] The present invention has at least the following beneficial effects: (1) This invention, through its novel deep-processing system and fine-processing system, can provide high-quality ultrapure water for semiconductor manufacturing processes. By employing a dual-cycle strategy of first-order and second-order circulation, it can stably and controllably output ultrapure water that meets the requirements of semiconductor processes. While ensuring that key indicators such as trace metals, TOC (total organic carbon), DO (dissolved oxygen), boron content, and hydrogen peroxide in the output water meet or exceed stringent semiconductor industry standards, it provides a stable output of ultrapure water.

[0038] (2) This invention automatically sets and adjusts the target decomposition dose for decomposition treatment by simulating the output of the pure water storage tank level, measuring the amount of micro-pollutants, and considering the actual demand for ultrapure water for downstream semiconductor processes. It controls the working state of the ultraviolet lamp ignition and the decomposition absorber, enabling the system to achieve energy-saving and consumption-reducing economic operation based on circulating water storage and adapting to downstream water consumption. It can provide high-quality ultrapure water for semiconductor processes for a long time, reduce the consumption of water production energy and operating load, and improve system efficiency and economy. Furthermore, by adjusting the variable current output of the ballast, the current intensity is reduced, the power output is lowered, and the lamp life is extended while reducing energy consumption. Based on the molecular dynamics model of reactive oxygen species decomposing TOC (VUV Dosing Calc EM), it not only provides an analytical means for controlling the target decomposition dose of first-order and second-order decomposition treatment, but also provides a predictive method for calculating the reduction of TOC in water. By coupling empirical coefficients, it achieves accurate prediction of the target decomposition dose and water quality index output of the mixed photolysis absorber, and can be extended to the design, selection, and engineering application of traditional ultraviolet decomposition total organic carbon devices, which has universal practical value.

[0039] (3) The coordinated operation of the control unit, online detection unit and dual circulation system of this invention not only keeps water quality indicators (such as trace metals, TOC, DO, boron content, hydrogen peroxide, etc.) within the set range, avoiding water quality fluctuations caused by changes in raw water quality, material performance degradation, leaching pollution from flowing materials, changes in equipment operating parameters, secondary micro-pollution, unreasonable energy matching of decomposition radiation source, and equipment aging, but also adjusts the working current and power of the radiation source according to the water volume and water quality stability, effectively reducing energy consumption while ensuring water quality, and providing an intelligent ultrapure water treatment and control method and device. Attached Figure Description

[0040] Figure 1 This is a process flow diagram for the stable output of ultrapure water for semiconductor processes according to the present invention; Figure 2 This is a process flow diagram of the fine treatment and second-order cycle of the present invention.

[0041] Explanation of reference numerals in the attached drawings: 11-Continuous electro-desalination device, 12-First-stage mixed photolysis absorber, 13-First membrane degasser, 101-First sampling point, 102-Second sampling point, 21-Pure water storage tank, 22-Membrane absorber, 23-Second-stage mixed photolysis absorber, 24-Second membrane degasser, 25-Membrane microparticle separator, 26-Sampling cell, 201-Third sampling point, 202-Fourth sampling point, 203-Fifth sampling point, 204-Sixth sampling point. Detailed Implementation

[0042] To better understand the above technical solutions, a detailed description of the solutions will be provided below in conjunction with the specification and specific implementation methods. Obviously, the described embodiments are merely 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.

[0043] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0044] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0045] See Figure 1 A method for controlling the stable output of ultrapure water for semiconductor processes specifically includes the following steps: S1 deep treatment purifies pretreated primary pure water into secondary pure water, including: S1.1 Deep desalination treatment: The primary pure water enters the continuous electro-desalination device 11 to further remove anions and cations, obtaining deep desalinated water; S1.2 First-order decomposition treatment: The deep desalinated water enters the first-order mixed photolysis absorber 12, passes through the first-order decomposition zone, and yields primary decomposed water. The first-order decomposition treatment employs several independently controlled radiation sources, including VUV / UV low-pressure high-intensity mercury vapor or low-pressure high-intensity mercury alloy arc discharge sources with a radiation wavelength of 185nm. The target decomposition dose for the first-order decomposition treatment is 100-800 mJ / cm³. 2 Continuously adjustable; S1.3 First-order absorption and exchange treatment: The water from the first decomposed water flows through the first-order absorption and exchange zone of the first-order mixed photolysis absorber 12, and undergoes positive adsorption treatment, complexation reaction treatment and ion polishing treatment in sequence. The ratio of the treatment time of positive adsorption treatment, complexation reaction treatment and ion polishing treatment is (1-4):(1-12):(1-6), preferably (1-4):(8-10):(1-4). Positive charge adsorption treatment uses a positive charge adsorbent, which is a positive charge adsorption resin with amine polyhydroxy functional groups or a mixed resin containing a positive charge adsorption resin with amine polyhydroxy functional groups. The complexation reaction treatment uses a boron absorbent; Ion polishing treatment uses a mixed ion exchanger with both basic and acidic groups.

[0046] S1.4 Degassing treatment: The water that has undergone first-stage absorption and exchange treatment enters the first membrane degasser 13 to remove dissolved gases and volatiles, and obtain secondary pure water; the secondary pure water at the outlet of the first membrane degasser 13 is sampled and detected online, and the online detection results are fed back to the control unit; S2 First-order circulation: Part of the secondary pure water flowing out of the first membrane degasser 13 is returned to steps S1.1-S1.4. The secondary pure water that is not returned is stored in the pure water storage tank 21. Based on the simulated output of the real-time change in the liquid level of the pure water storage tank 21, the actuator is driven to distribute the return water volume of the secondary pure water according to the proportional opening to form the first-order circulation ratio. Based on the amount of micro-contamination in the primary pure water and the first-order circulation ratio, the target decomposition dosage of the first-order decomposition treatment is adjusted to control the amount of micro-contamination in the secondary pure water.

[0047] Preferably, the first-order cycle ratio R m : R m =Q mr / Q me Q me =Q mt -Q mr R m Between 0.1 and 10, Among them, Q mt Q represents the total amount of secondary pure water obtained from deep treatment. mrQ represents the amount of secondary pure water returned. me This indicates the amount of secondary pure water stored in the pure water storage tank 21.

[0048] After deep treatment and primary circulation, the secondary pure water in pure water storage tank 21 reaches the following quality: Resistivity > 18.1 MΩ·cm, TOC < 5.0 μg / l, B < 5 ng / l, DO < 5 μg / l; preferably, resistivity > 18.2 MΩ·cm, TOC < 3 μg / l, B < 3 ng / l, DO < 2 μg / l.

[0049] S3 Refining: Purifies secondary pure water into ultrapure water, including: S3.1 Hydrogen charging treatment: Secondary pure water is output from the pure water storage tank 21 and enters the membrane absorber 22. Hydrogen gas with a purity greater than 99.9% is introduced into the membrane absorber 22 to obtain hydrogen-charged water with a dissolved hydrogen concentration of more than 0.05 mg / L. S3.2 Second-order decomposition treatment: Hydrogen-filled water enters the second-order mixed photolysis absorber 23, passes through the second-order decomposition zone, and yields secondary decomposed water. The second-order decomposition treatment employs several independently controlled radiation sources, including VUV / UV low-pressure high-intensity mercury vapor or low-pressure high-intensity mercury alloy arc discharge sources with a radiation wavelength of 185nm. The target decomposition dose for the second-order decomposition treatment is 200-1000 mJ / cm². 2 Continuously adjustable; S3.3 Second-stage absorption and exchange treatment: The water from the secondary decomposition flows through the second-stage absorption and exchange zone of the second-stage mixed photolysis absorber 23, and then undergoes catalytic decomposition treatment and ion polishing treatment in sequence. The ratio of the treatment time for catalytic decomposition treatment and ion polishing treatment is 1:(1-50), preferably 1:(2.5-20). The catalytic decomposition process uses a metal catalyst, preferably a supported metal nanoparticle catalyst. Ion polishing treatment uses a mixed ion exchanger with both basic and acidic groups.

[0050] S3.4 Degassing and Ultrafiltration: The water that has undergone the second-stage absorption and exchange treatment enters the second membrane degasser 24 and membrane microparticle separator 25 for degassing and solid-liquid separation to remove dissolved gases, volatiles and microparticles, and obtain ultrapure water.

[0051] S4 Second-order cycle: Based on the downstream semiconductor process water consumption, output ultrapure water with a margin, and use a voltage regulator actuator to distribute the remaining ultrapure water back to steps S3.1-3.4 to form a second-order cycle ratio; adjust the target decomposition dosage of the second-order decomposition treatment according to the amount of micro-contamination in the secondary pure water and the second-order cycle ratio, control the amount of micro-contamination in the ultrapure water, and monitor the amount of micro-contamination in the output ultrapure water online in real time, and compare it with the ultrapure water micro-contamination amount obtained by the aforementioned preset and controlled methods.

[0052] Second-order cycle ratio R p satisfy: R p =Q pr / Q pe Q pe =Q pt -Q pr Among them, R p In the range of 0.2-0.8, Q pt Q represents the total amount of ultrapure water obtained after fine treatment. pr Q represents the volume of ultrapure water returned. pe This indicates the amount of ultrapure water used in downstream semiconductor processes; The ultrapure water produced by the above method has the following quality: Trace metals < 0.1 ng / l, TOC < 0.5 μg / l, DO < 1 μg / l, B < 1 ng / l, H2O2 < 1 μg / l, and particle number concentration greater than 0.05 μm < 0.1 pcs / mL.

[0053] To operate the aforementioned control method, the present invention also provides a corresponding apparatus, comprising a circulating deep treatment system, a pure water storage tank 21, and a circulating fine treatment system connected in sequence, wherein: (1) A deep processing system, including: (1.1) Deep desalination equipment, including at least one of continuous electro-desalination device 11, mixed ion exchange tower, and composite ion exchange tower; (1.2) First-order hybrid photolysis absorber 12, which integrates and is compatible with the first-order decomposition region and its downstream first-order absorption exchange region; The UV target decomposition dose in the first-order decomposition region is 300-800 mJ / cm. 2 The TOC concentration in the outlet water of the first-order mixed photolysis absorber 12 is below 5 μg / l, preferably less than 3 μg / l, and more preferably less than 2 μg / l; Along the direction of water flow, the first-order absorption and exchange zone sequentially includes a positively charged adsorption layer, a complexing reaction layer, and an ion polishing layer. Based on the treatment time ratio, the thickness ratio of the positively charged adsorption layer, the complexing reaction layer, and the ion polishing layer is designed to be approximately (1-4):(1-12):(1-6), preferably (1-4):(8-10):(1-4). The positively charged adsorption layer includes a positively charged adsorbent, which is either a positively charged adsorption resin with amine polyhydroxy functional groups or a mixed resin containing positively charged adsorption resins with amine polyhydroxy functional groups. The complexing reaction layer includes a boron absorbent. The ion polishing layer includes a mixed ion exchanger with basic and acidic groups, respectively. (1.3) The first membrane degasser 13 includes a membrane contact degassing device; (2) First-stage circulation pipeline: In addition to being normally connected to the pure water storage tank 21, the outlet of the first membrane degasser 13 is also equipped with a first-stage circulation pipeline, which is connected to the inlet of the desalination equipment to return a certain proportion of the secondary pure water to the circulation deep treatment system. The first-stage detection unit includes a level detector installed in the pure water storage tank 21, a first sampling point 101 installed at the inlet of the deep desalination equipment, a second sampling point 102 installed at the outlet of the first membrane degasser 13, and detection equipment connecting the sampling points (101, 102). The detection equipment includes, but is not limited to, at least one of a TOC analyzer, a dissolved oxygen analyzer, a boron analyzer, and a dissolved silica analyzer. The measurement data from the detection equipment is transmitted to the control unit. Based on the first-stage circulation ratio and the amount of micro-contamination in the primary pure water, the target decomposition dose of the first-stage decomposition treatment is adjusted to control the amount of micro-contamination in the secondary pure water; or, based on the first-stage circulation ratio, the amount of micro-contamination in the primary pure water, and the target amount of micro-contamination in the secondary pure water, the target decomposition dose of the first-stage decomposition treatment is adjusted. That is, the above parameters are interrelated and adjustable.

[0054] (3) A circulating fine treatment system, including: (3.1) Membrane absorber 22, including a hydrogen dissolving membrane and a hydrogen supply line, is used to fill the secondary pure water with dissolved hydrogen gas to obtain hydrogen-filled water with a dissolved hydrogen concentration of more than 0.05 mg / L; (3.2) Second-order hybrid photolysis absorber 23, integrated and compatible with the second-order decomposition region and its downstream second-order absorption exchange region; the ultraviolet target decomposition dose in the second-order decomposition region is 200-1000 mJ / cm. 2 The TOC concentration in the outlet water of the second-order mixed photolysis absorber 23 is below 0.5 μg / l, preferably below 0.3 μg / l; In the direction of water flow, the second-order absorption and exchange zone includes a catalytic reaction layer and an ion polishing layer in sequence. According to the ratio of treatment time, the thickness ratio of the catalytic reaction layer and the ion polishing layer is 1:(1-50), preferably 1:(1.2-50), and more preferably 1:(2.5-20). (3.3) The second membrane degasser 24 and the membrane microparticle separator 25 include a membrane contact degasser and an ultrafiltration unit connected in sequence; (4) Second-stage circulation pipeline: In addition to the downstream water point that is normally connected to the ultrapure water output port, the outlet of the membrane microparticle separator 25 is also equipped with a second-stage circulation pipeline, which is connected to the pure water storage tank 21 to return a certain proportion of ultrapure water for fine treatment, so as to meet the real-time changing process water demand while ensuring water quality requirements. The second-stage detection unit includes a third sampling point 201 located at the outlet of the membrane microparticle separator 25 and a detection device connected to the third sampling point 201. This detection device can be shared with or separate from the detection device in the first-stage detection unit, and includes, but is not limited to, at least one of a TOC analyzer, dissolved oxygen analyzer, boron analyzer, microparticle analyzer, H2O2 analyzer, and dissolved silica analyzer. The unit transmits the measurement data from the detection device to the control unit. Based on the amount of micro-contamination in the secondary pure water and the second-stage circulation ratio, the target decomposition dose of the second-stage decomposition treatment is adjusted to control the amount of micro-contamination in the ultrapure water; or, based on the amount of micro-contamination in the secondary pure water, the second-stage circulation ratio, and the target amount of micro-contamination in the ultrapure water, the target decomposition dose of the second-stage decomposition treatment is adjusted. In other words, the above parameters are interrelated and adjustable.

[0055] (5) Control unit, the control unit is connected to the aforementioned first-order detection unit and second-order detection unit, including but not limited to being connected to the liquid level detector, the first distribution actuator and the second distribution actuator. Based on the feedback value of the liquid level detector, the first distribution actuator is driven to distribute the return water volume of the secondary pure water at a proportional opening to form a first-order circulation ratio. Based on the amount of ultrapure water used in the process, the second distribution actuator is driven to distribute the return water volume of the ultrapure water at a proportional opening to form a second-order circulation ratio.

[0056] To facilitate a better understanding of the method and apparatus for controlling the stable output of ultrapure water for semiconductor processes according to the present invention, the overall process and control method are further explained based on the aforementioned core control method and apparatus: During the startup and operation phase, all light sources designed for the first-order and second-order decomposition zones can be turned on to perform micro-pollution treatment in maximum power mode, so that the output ultrapure water can quickly meet the requirements for water consumption and water quality. During the stable operation phase, based on the detection results of the micro-contamination levels in the primary and secondary pure water by the detection unit, and the resulting first-order circulation ratio, the target decomposition dose for the first-order decomposition treatment is adjusted according to the preset micro-contamination level in the secondary pure water. When the micro-contamination level in the secondary pure water is low, especially significantly better than the preset or predicted value, the optimal lower target decomposition dose is calculated by the TOC kinetic model. This allows for adjustment of the current output of a portion of the radiation source in the first-order decomposition zone by controlling the ballast, reducing the current intensity and power output. Simultaneously, based on the real-time detection results from the online detection device, it is determined whether the micro-contamination level in the secondary pure water at the outlet of the first membrane degasser 13 meets the preset requirements. If the requirements are met, the radiation source status can be maintained or further adjustment can be made based on the detected micro-contamination indicators. When the amount of micro-contamination in the secondary pure water rises above the preset value (i.e., a certain micro-contamination index exceeds the threshold), the optimal higher target decomposition dose is calculated by the TOC kinetic model. The current output of part of the radiation source in the first-order decomposition zone can be adjusted by regulating the ballast, gradually increasing the current intensity and power output. At the same time, based on the real-time detection results of the online detection device, it is determined whether the amount of micro-contamination in the secondary pure water at the outlet of the first membrane degasser 13 meets the preset requirements. The option is to maintain the radiation source state or continue to increase the current intensity and power output until the requirements are met.

[0057] When the amount of ultrapure water used in downstream semiconductor processes decreases, especially when it is significantly lower than the average consumption of process water and reaches a stable state, a high second-order circulation ratio is formed for a long time. As a result, the secondary pure water in the pure water storage tank 21 is diluted more. The optimal lower target decomposition dose is calculated by the TOC kinetic model. The operating current of the radiation source in the second-order decomposition zone can be appropriately reduced by adjusting the ballast, thereby reducing the power output. Based on the monitoring of the amount of micro-contamination in the ultrapure water at the outlet of the membrane microparticle separator 25, the radiation dose provided by the second-order mixed photolysis absorber 23 is determined under the premise of ensuring system stability.

[0058] In general, the first-order circulation ratio, the amount of micro-contamination in the primary pure water, the amount of micro-contamination in the secondary pure water, and the target decomposition dose of the first-order decomposition treatment are closely related; similarly, the amount of micro-contamination in the secondary pure water, the amount of micro-contamination in the ultrapure water, the second-order circulation ratio, and the target decomposition dose of the second-order decomposition treatment are closely related. Based on multiple simulation experiments, this invention proposes the aforementioned method and apparatus for controlling the stable output of ultrapure water for semiconductor processes. Example

[0059] The stable output method for ultrapure water in semiconductor processes described in this embodiment is applied to a pilot line for the domestic substitution of ultrapure water in nanoscale semiconductor manufacturing. The apparatus specifically includes a circulating deep treatment system, a pure water storage tank 21, and a circulating fine treatment system connected in sequence. The circulating deep treatment system mainly provides S1 deep treatment and S2 first-order circulation; the circulating fine treatment system is described in the appendix. Figure 2 It mainly provides S3 fine processing and S4 second-order loop.

[0060] The specific processing steps are as follows: S1 deep treatment purifies pretreated primary pure water into secondary pure water, including: S1.1 Deep desalination treatment: The pretreated primary pure water enters the continuous electro-desalination unit 11 to further remove anions and cations, and obtain deep desalinated water; S1.2 First-order decomposition treatment: Deep demineralized water enters the first-order mixed photolysis absorber 12 (the first-order mixed photolysis absorber 12 is compatible with the first-order decomposition zone and its downstream first-order absorption exchange zone), and after decomposition treatment, primary decomposed water is obtained; the first-order decomposition treatment uses nine independently controlled 185nm low-pressure high-intensity mercury discharge lamps of 155W each (3 groups × 3 units, VioPure); the target UV decomposition dose for the first-order decomposition treatment is 100-800mJ / cm². 2 Continuously adjustable; S1.3 First-order absorption and exchange treatment: This includes positive charge adsorption treatment, complexation reaction treatment, and ion polishing treatment in sequence, with the treatment time ratio of positive charge adsorption treatment, complexation reaction treatment, and ion polishing treatment being 1:8:2; wherein, the positive charge adsorption treatment uses a positively charged adsorbent, which is a positively charged adsorption resin with amine polyhydroxy functional groups; the complexation reaction treatment uses a boron absorbent; and the ion polishing treatment uses a mixed ion exchanger with basic and acidic groups respectively.

[0061] S1.4 Degassing treatment: The water that has undergone first-stage absorption and exchange treatment enters the first membrane degasser 13 to remove dissolved gases and volatiles, and obtain secondary pure water; the secondary pure water at the outlet of the first membrane degasser 13 is sampled and detected online, and the online detection results are fed back to the control unit; S2 First-order circulation: Part of the secondary pure water flowing out of the first membrane degasser 13 is recycled back to the circulation in steps S1.1-S1.4. The secondary pure water that is not recycled is stored in the pure water storage tank 21. The amount of water stored and the amount of water recycled are controlled by the liquid level detector. The actuator is driven to distribute the water volume according to the proportional opening based on the feedback value of the liquid level detector, forming a first-order circulation ratio. After deep treatment and first-stage circulation, the secondary pure water in the pure water storage tank 21 has a water quality of at least: resistivity 18.10 MΩ·cm, TOC concentration 2.1 μg / l, boron (B) concentration 2 ng / l, and DO concentration 1.3 μg / l.

[0062] S3 Fine Processing: S3.1 Hydrogen charging treatment: Secondary pure water output from pure water storage tank 21 enters membrane absorber 22. Membrane absorber 22 is equipped with gas transfer membrane ArrayforceTM 10×28 (provided by Cobetter). Hydrogen gas with a purity greater than 99.9% is introduced into membrane absorber 22. The hydrogen concentration of hydrogen-charging water at the liquid phase outlet of membrane absorber 22 is monitored by Dextens 62101 hydrogen dissolution instrument connected to the fourth sampling point 202 and found to be 0.05 mg / L. S3.2 Second-order decomposition treatment: Hydrogen-filled water at SV=500h -1The water enters a second-order hybrid photolysis absorber 23 (which is compatible with the second-order decomposition region and its downstream second-order absorption exchange region), undergoes second-order decomposition treatment, and yields secondary decomposed water. The second-order decomposition treatment uses 12 independently controlled 185nm low-pressure high-intensity mercury discharge lamps (6 groups × 2, VioPure). The target UV decomposition dose for the second-order decomposition treatment is 200-1000 mJ / cm². 2 Continuously adjustable; S3.3 Second-order absorption and exchange treatment: The water from the secondary decomposition process was sequentially subjected to catalytic decomposition treatment and ion polishing treatment, with a treatment time ratio of 1:7. The catalytic decomposition treatment used platinum-based nanoparticle catalyst Pd@PS-DVB-QA (laboratory-prepared, particle size measured as 1.5±0.2nm using JEM-100CX image); the ion polishing treatment used electronic-grade UPS resin Monojet 6040U (Sunresin).

[0063] The outlet of the second-order hybrid photolysis absorber 23 is provided with a fifth sampling point 203, which is connected to a combined sampling valve of the ALH2O2 Analyzer and the Sievers M500e Online TOC Analyzer for online analysis of H2O2 and TOC mass concentrations. S3.4 Degassing and Ultrafiltration: The water that has undergone two-stage absorption and exchange treatment enters the second membrane degasser 24 for degassing (using the SEPAREL EF-120 deoxygenation membrane, provided by Sinochem), and then enters the membrane microparticle separator 25 for solid-liquid separation (using the APA6SN ultrafiltration membrane, provided by Cobetter) to remove dissolved gases, volatiles and microparticles, and obtain ultrapure water.

[0064] S4 Second-Stage Circulation: Based on the downstream semiconductor manufacturing process water consumption, a margin of ultrapure water is output. A voltage regulator actuator distributes the remaining ultrapure water back to the system for recirculation in steps S3.1-3.4, forming the circulation ratio for the second-stage treatment. The amount of micro-contamination in the output ultrapure water is monitored online in real time, and the target decomposition dosage for the second-stage decomposition treatment is adjusted according to the amount of ultrapure water used in the process. A sampling pool 26 is set at the outlet of the membrane microparticle separator 25, with a sixth sampling point 204. The sampled water from the sixth sampling point 204 is delivered in real time to three analyzers: Orbisphere 510, PMS Ultra DI50, and NexION 5000 ICP-MS, to detect the concentrations of DO, microparticles (>0.05 μm), and boron online, respectively, allowing for real-time online monitoring of the output ultrapure water.

[0065] After the water quality indicators of the ultrapure water were basically stable, the water was continuously supplied for two days, and the water quality became more stable. The detection data of the membrane microparticle separator 25 outlet in this embodiment are shown in Table 1.

[0066] Table 1. Detection data of various micro-pollution indicators

[0067] Catalyst space velocity of 500 h⁻¹ during catalytic decomposition treatment -1 The catalyst packing height is 0.1m, the UPS resin layer height in the ion polishing zone is 0.7m, and the second-order hybrid photolysis absorber 23 is a Type-Ⅱ-1000 model with a standard configuration of 12 185nm lamps (6 groups × 2 lamps). The UV target decomposition dose of the actual lamps in the second-order hybrid photolysis absorber 23 was verified using VUV Dosing Calc EM: based on the experimental model calculations, the design dose to achieve the TOC target reduction concentration is 514 mJ / cm³. 2 The dose ratio adjustment factor is 1.36, therefore the calculated radiation dose of the second-order hybrid photolysis absorber 23 is 698 mJ / cm². 2 Therefore, the actual calculated TOC concentration is 0.2 μg / L, which is basically consistent with the measured value of 0.19 μg / L. Other design data are shown in Table 2.

[0068] Table 2 Design parameters of the second-order hybrid photolysis absorber 23 (U-PMB)

[0069] Using the above-mentioned device, and following the control and monitoring methods, the quality of the output ultrapure water can be made to meet the following standards: TOC < 0.5 μg / l, DO < 1 μg / l, B < 1 ng / l, H2O2 < 1 μg / l, and the number concentration of particles larger than 0.05 μm < 0.1 pcs / mL.

[0070] By changing the additional circulation coefficient and adjusting the actuator opening, second-order circulating return water volumes Q of 1, 1.5, 2, 2.5, and 3 CMH were obtained respectively. pr The TOC values ​​at the outlet of the water collection chamber of the second-order hybrid photolysis absorber 23 were recorded and compared with the calculated values ​​by VUV Dosing Calc EM. The experimental data are shown in Table 3. Table 3. Experimental data record of the second-order hybrid photolysis absorber 23

[0071] The results show that the experimental study of the second-order hybrid photolysis absorber 23 is reproducible. The relative error between the predicted second-order decomposition concentration using VUV Dosing CalcEM and the measured value at the outlet of the second-order hybrid photolysis absorber 23 is small, indicating high design accuracy. Therefore, this invention can set suitable water quality and output flow rate according to the downstream semiconductor process water requirements, ensuring a stable and continuous water supply while maintaining high water quality. Furthermore, it can quickly adjust and predict the technical effect according to changes in downstream demand, and adjust the radiation source parameters in the decomposition zone. This reduces energy consumption and saves costs while ensuring a high-quality and stable supply of ultrapure water.

[0072] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the invention is intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope.

Claims

1. A method for controlling the stable output of ultrapure water for semiconductor processes, characterized in that, Includes the following steps: S1 Deep Treatment: Deep desalination, first-stage decomposition, first-stage absorption and exchange, and degassing treatment are performed on primary pure water to obtain secondary pure water. S2 First-order circulation: A portion of the secondary pure water obtained in step S1 is recirculated for further treatment in step S1. The remaining secondary pure water is stored in a pure water storage tank. Based on the simulated output of the pure water storage tank level, the recirculation volume of the secondary pure water is proportionally allocated to form a first-order circulation ratio, determined according to the amount of micro-contamination in the primary pure water. and first-order cycle ratio R m After first-order decomposition and first-order absorption-exchange treatments, the target decomposition dose D of the first-order decomposition treatment is adjusted. pm The amount of micro-pollutants in the secondary pure water was obtained. Micro-pollutants in secondary purified water Satisfying equation (1): （1）； Among them, RE mdi To improve the efficiency of deep desalination treatment, D pm The target decomposition dose for first-order decomposition processing. This refers to the amount of trace pollutants in the secondary purified water. This refers to the amount of micro-contaminants in a single batch of pure water. Rm is the cycle ratio of the first-order processing. K m1 K m2 It is the reaction rate constant; S3 Fine Treatment: The secondary pure water output from the pure water storage tank is hydrogenated to make the dissolved hydrogen concentration above 0.05 mg / L. Then, it undergoes second-stage decomposition treatment, second-stage absorption and exchange treatment, degassing and ultrafiltration treatment to obtain ultrapure water. S4 Second-order cycle: Based on the downstream semiconductor process water consumption, ultrapure water is stably output, and the remaining ultrapure water is returned for further treatment in step S3; wherein, based on the ultrapure water consumption for the process, the return water volume of ultrapure water is allocated proportionally to form a second-order cycle ratio, and based on the amount of micro-contamination in the secondary pure water... Second-order cycle ratio R p The characteristic coefficient λ of the pipeline network is subjected to second-order decomposition treatment, second-order absorption and exchange treatment, degassing and ultrafiltration treatment, and the target decomposition dose D of the second-order decomposition treatment is adjusted. pe The amount of micro-pollutants in ultrapure water was obtained. Micropollutants in ultrapure water Satisfying equation (2): （2）； Among them, D pe The target decomposition dose for the second-order decomposition process. This refers to the amount of micro-pollution in the secondary pure water. R p The cycle ratio for the second-order decomposition process. λ is the characteristic coefficient of the pipeline network, satisfying equation (3): （3） L is the length of the pipeline network; The concentration gradient of micro-contaminant leaching from the ultrapure water reflux network is given by v, which is the second-order decomposition treatment rate, and Kt is the time constant. p1 K p2 K p3 It is the reaction rate constant; Furthermore, the first-order decomposition process and the second-order decomposition process each employ several independently controlled ultraviolet radiation sources for ultraviolet decomposition. The target decomposition dose for first-order decomposition treatment is 100-800 mJ / cm³. 2 Continuously adjustable; The target decomposition dose for the second-order decomposition treatment is 200-1000 mJ / cm³. 2 Continuously adjustable.

2. The control method as described in claim 1, characterized in that, The secondary purified water in the pure water storage tank meets the following quality standards: Resistivity > 18.1 MΩ·cm, TOC < 5.0 μg / l, B < 5 ng / l, DO < 5 μg / l.

3. The control method as described in claim 1 or 2, characterized in that, The output ultrapure water quality reaches: Trace metals < 0.1 ng / l, TOC < 0.5 μg / l, DO < 1 μg / l, B < 1 ng / l, H2O2 < 1 μg / l, and the number concentration of particles larger than 0.05 μm < 0.1 pcs / mL.

4. The control method as described in claim 1 or 2, characterized in that, The first-order absorption-exchange treatment includes positive charge adsorption treatment, complexation reaction treatment and ion polishing treatment in sequence. The ratio of the treatment time of positive charge adsorption treatment, complexation reaction treatment and ion polishing treatment is (1-4):(1-12):(1-6). The second-order absorption-exchange treatment includes catalytic decomposition treatment and ion polishing treatment in sequence, with the treatment time ratio of catalytic decomposition treatment to ion polishing treatment being 1:(1-50).

5. An apparatus for operating the control method according to any one of claims 1-4, characterized in that, It includes a circulating deep treatment system, a pure water storage tank, and a circulating fine treatment system connected in sequence; The circulating deep treatment system includes a deep desalination device, a first-stage mixed photolysis absorber, and a membrane degasser. The outlet of the membrane degasser is connected to the pure water storage tank and the inlet of the deep desalination device in a controlled manner. The circulating fine treatment system includes a membrane absorber, a second-stage mixed photolysis absorber, a membrane degasser, and a membrane microparticle separator. The outlet of the membrane microparticle separator is connected to the ultrapure water point and the pure water storage tank in a controlled manner. The first-order mixed photolysis absorber is compatible with the first-order decomposition region and its downstream first-order absorption-exchange region; the second-order mixed photolysis absorber is compatible with the second-order decomposition region and its downstream second-order absorption-exchange region; the membrane absorber includes a hydrogen-dissolving membrane and a hydrogen supply pipeline, providing hydrogen-filled water with a dissolved hydrogen concentration of 0.05 mg / L or higher to the downstream second-order mixed photolysis absorber.

6. The apparatus as claimed in claim 5, characterized in that, It also includes a control unit and a detection unit; The detection unit includes a level detector installed in the pure water storage tank, and sampling points installed at the inlet of the deep desalination equipment, the outlet of the membrane degasser and the membrane microparticle separator, as well as detection equipment connected to the sampling points. The control unit is connected to the level detector, the first distribution actuator, and the second distribution actuator. Based on the feedback value from the level detector, the first distribution actuator is driven to distribute the return water volume of the secondary pure water at a proportional opening to form a first-order circulation ratio. Based on the amount of ultrapure water used in the process, the second distribution actuator is driven to distribute the return water volume of the ultrapure water at a proportional opening to form a second-order circulation ratio.

7. The apparatus as claimed in claim 6, characterized in that, In the direction of water flow, the first-order absorption and exchange region includes a stacked positively charged adsorption layer, a complexation reaction layer, and an ion polishing layer, while the second-order absorption and exchange region includes a stacked catalytic decomposition layer and an ion polishing layer. The control unit adjusts the target decomposition dose in the first-order decomposition zone and / or the target decomposition dose in the second-order decomposition zone based on the feedback results from the detection equipment.

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