An electrothermal adsorption exhaust gas treatment device for RPS dissociation rate testing

Abstract

This invention discloses an electrothermal adsorption-type exhaust gas treatment device for RPS dissociation rate testing in the field of remote plasma sources. The device comprises a heating system, a steam injection system, a cooling system, and an adsorption system connected in sequence. The heating system includes a segmented reaction tube with a temperature field that increases progressively from the inlet to the outlet. The adsorption system includes a primary solid adsorption layer and a secondary circulating spray system. The segmented reaction tube has a three-section coaxial nested structure, including a preheating section, a main decomposition section, and a deep pyrolysis section. Each section is independently temperature-controlled and heated by a high-frequency induction coil. This electrothermal adsorption exhaust gas treatment device achieves the step-by-step decomposition of NF3 through segmented heating. Combined with a multi-stage adsorption system for efficient neutralization of harmful gases (such as HF), it effectively removes harmful substances from exhaust gas and reduces environmental pollution.

Description

Technical Field

[0001] This invention relates to the field of remote plasma source technology, and in particular to an electrothermal adsorption type exhaust gas treatment device for RPS dissociation rate testing. Background Technology

[0002] A remote plasma source (RPS) is an advanced plasma generation device, also known as a remote high-density plasma generator, commonly used in process chamber cleaning and etching processes during integrated circuit manufacturing. Its core function is to efficiently and stably ionize the cleaning gas (NF3) or process gas (NH3, O2), thereby significantly enhancing the reactivity of the reactant gas and the consistency of the process. Compared to traditional plasma sources, remote plasma sources have a physical separation between the plasma generation region and the processing region. After plasma generation, it is transported to the processing region, where active particles (such as free radicals, ions, and neutral particles) diffuse during transport. This design allows the plasma to act more uniformly and efficiently on the surface of the material to be treated.

[0003] Dissociation rate is one of the important parameters characterizing the reaction efficiency of remote plasma sources. It refers to the proportion of reactant gases that are dissociated into active species (such as free radicals, mononuclear ions, polynuclear ions, and neutral atoms) in a strong electric field environment. A higher and more stable dissociation rate means that a higher plasma density can be obtained under the same input power, thereby reducing the cleaning time of the process chamber and improving processing efficiency and quality. Therefore, the measurement of RPS dissociation rate and its stability is crucial.

[0004] However, NF3 is a potent greenhouse gas (GWP=17200), and direct emission is not advisable. The residual gas after RPS dissociation rate testing requires treatment. For undissociated NF3... 3， Traditional treatment methods, such as high-temperature incineration, suffer from high energy consumption (requiring temperatures above 1200℃), while catalytic methods are prone to deactivation due to fluorine corrosion. Existing electric heating technologies suffer from low decomposition efficiency (<95%) and secondary pollution from corrosive byproduct gases (such as F2 and HF). Summary of the Invention

[0005] This application provides an electrothermal adsorption type exhaust gas treatment device for RPS dissociation rate testing, which solves the problem of inconvenient exhaust gas treatment after RPS dissociation rate testing in the prior art, thereby efficiently treating the remaining gas after RPS dissociation rate testing.

[0006] This application provides an electrothermal adsorption type exhaust gas treatment device for RPS dissociation rate testing, comprising: a heating system, a steam injection system, a cooling system, and an adsorption system connected in sequence; the heating system includes a segmented reaction tube, the temperature field of which increases from the inlet end to the outlet end; the adsorption system includes a primary solid adsorption layer and a secondary circulating spray system.

[0007] The beneficial effects of the above embodiments are as follows: the electrothermal adsorption exhaust gas treatment equipment achieves the stepwise decomposition of NF3 through segmented heating, and combined with the multi-stage adsorption system to efficiently neutralize harmful gases (such as HF), it can effectively remove harmful substances in exhaust gas and reduce environmental pollution.

[0008] Based on the above embodiments, this application can be further improved as follows:

[0009] In one embodiment of this application, the segmented reaction tube of the heating system is a three-segment coaxial nested structure, including a preheating segment, a main decomposition segment, and a deep pyrolysis segment. Each segment is independently temperature-controlled and heated by a high-frequency induction coil. By precisely adjusting the reaction temperature gradient (500℃→1000℃) through three-segment independent temperature control, the NF3 decomposition efficiency is improved (>99.5%), while high-frequency induction heating reduces energy consumption by 30%.

[0010] In one embodiment of this application, the steam injection system is a ring-shaped injection device that controls the injection rate of ultrapure steam via a mass flow meter, dynamically matching the molar ratio with NF3. Dynamically matching the molar ratio of steam to NF3 (0.8:1~1.2:1) ensures that F2 is fully converted to HF, reducing the risk of secondary contamination from byproducts.

[0011] In one embodiment of this application, a heat exchanger is provided between the outlet of the steam injection system and the inlet of the heating system to recover waste heat from the exhaust gas to preheat the intake gas. By recovering waste heat, the intake gas temperature is increased to 300°C, reducing the energy consumption of the heating system (overall power consumption ≤ 1.5 kWh / m³ NF3) and improving energy utilization efficiency.

[0012] In one embodiment of this application, the secondary circulating spray system of the adsorption system is equipped with a pH feedback device for dynamically adjusting the concentration and flow rate of the spray liquid. The pH value of the spray liquid is monitored in real time, and the Ca(OH)2 solution concentration (10wt%) is adjusted to ensure HF neutralization efficiency (HF concentration in the tail gas < 1 ppm) while preventing scaling in the adsorption tower.

[0013] In one embodiment of this application, the outlet of the steam injection system is further provided with a particle collection tank for capturing solid particles generated during the reaction. Collecting solid particles (such as CaF2 precipitate) generated during the reaction prevents pipe blockage and extends the service life of the equipment.

[0014] In one embodiment of this application, an emergency pressure relief valve is provided between the air inlet of the heating system and the inlet of the adsorption system, for opening and releasing pressure when the pressure exceeds the limit. This rapid pressure relief in case of abnormal pressure prevents the reaction tube or pipeline from bursting, thus improving the safety of equipment operation.

[0015] In one embodiment of this application, a gas content detection system is also included. This system comprises an NF3 detector and an HF sensor, used to monitor the concentrations of NF3 and HF in the exhaust gas in real time and feed this information back to the control system to adjust the heating power and steam injection rate. By monitoring the NF3 and HF concentrations in real time and dynamically adjusting the heating power and steam flow rate, the exhaust gas treatment meets the standards (NF3 decomposition rate > 99%, HF < 1 ppm), adapting to high-concentration shock load conditions. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0017] Figure 1 This is a front view schematic diagram of a dissociation rate testing device for a remote plasma source according to an embodiment of this application;

[0018] Figure 2 This is a three-dimensional structural schematic diagram of a dissociation rate testing device for a remote plasma source according to an embodiment of this application;

[0019] Figure 3 This is a schematic diagram showing the relationship between the components in the dissociation rate acquisition process in an embodiment of this application;

[0020] Figure 4 This is a schematic diagram of the RPS control platform display screen in the embodiments of this application;

[0021] Figure 5 This is a flowchart illustrating the method for obtaining the dissociation rate in an embodiment of this application.

[0022] Figure 6 This is a schematic diagram of the exhaust gas treatment equipment in the embodiments of this application;

[0023] Figure 7 This is a connection diagram of the control module of the exhaust gas treatment equipment in the embodiments of this application;

[0024] Figure 8 This is a flowchart illustrating the operation of the exhaust gas treatment device in the embodiments of this application;

[0025] Figure 9 This is a schematic diagram of the traditional structure of the water-cooled pipe at the air outlet, where 9(a) is a schematic diagram of the internal structure and 9(b) is a schematic diagram of the external structure.

[0026] Figure 10 This is a schematic diagram of the structure of the water-cooled pipe at the air outlet in the embodiment of this application, wherein 10(a) is a schematic diagram of the internal structure and 10(b) is a schematic diagram of the external structure;

[0027] Figure 11 This is a flowchart illustrating the steps of a method for diagnosing a fault in the outlet water pipe of a remote plasma source according to an embodiment of this application.

[0028] Figure 12 A flowchart for evaluating the importance relationship between scaling, clogging, and microleakage and process parameters;

[0029] Figure 13 A flowchart for constructing a decision tree to evaluate importance relationships;

[0030] Figure 14 A diagram showing the ranking of the importance of scaling, clogging, and microleakage with respect to process parameters.

[0031] Among them, 100-remote plasma source; 101-air inlet; 102-equipment status display screen; 103-water cooling pipe; 1031-cooling water channel; 104-etching test platform; 105-etching observation window; 106-RPS inlet and outlet; 107-gas pressure gauge; 108-sampling gas pressure gauge; 200-gas ionization detection device; 201-Fourier transform infrared spectrometer; 202-ionized gas sample collection pipeline; 203-spectrum exhaust gas output pipeline; 300-RPS control test platform; 301-test platform display screen; 302-test platform status operation indicator light; 400-host computer system; 500-vacuum pump; 501-exhaust gas transmission pipeline; 600-exhaust gas treatment equipment; 601-exhaust gas treatment equipment inlet; 602-exhaust gas treatment equipment outlet. Detailed Implementation

[0032] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0033] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] Embodiment 1 of this application provides a dissociation rate testing device for a remote plasma source, which solves the problem of inconvenience in testing the dissociation rate of RPS in the prior art, thereby making it convenient and accurate to test the dissociation rate of RPS.

[0035] Embodiment 2 of this application provides an electrothermal adsorption type exhaust gas treatment device for RPS dissociation rate testing, which solves the problem of inconvenient exhaust gas treatment after RPS dissociation rate testing in the prior art, thereby efficiently treating the remaining gas after RPS dissociation rate testing.

[0036] Embodiment 3 of this application provides a heat dissipation water pipe structure for the outlet of a remote plasma source, which solves the problems in the prior art where uneven temperature of the heat dissipation water pipe affects the accuracy of the dissociation rate test and the heat dissipation efficiency of the heat dissipation water pipe is low, thereby improving the temperature uniformity and heat dissipation efficiency of the heat dissipation water pipe.

[0037] Embodiment 4 of this application provides a fault diagnosis method for the outlet water pipe of a remote plasma source, which solves the problem of lack of fault monitoring for the outlet heat dissipation water pipe in the prior art, thereby achieving accurate identification of scaling, blockage and leakage faults.

[0038] Example 1:

[0039] like Figure 1-3 As shown, a dissociation rate testing device for a remote plasma source includes a remote plasma source 100, a gas ionization detection device 200, a Fourier transform infrared spectrometer 201, an RPS control platform 300, a host computer system 400, and an exhaust gas treatment device 600. Figure 2 (The text is omitted here.)

[0040] The remote plasma source 100 is used to dissociate process gases and perform thin film deposition and cleaning processes under vacuum conditions. The remote plasma source 100 includes a dissociation chamber, an inlet 101, an outlet, and RPS inlet / outlet water inlets 106. The outlet is connected to the etching stage 104 through an outlet water-cooling pipe 103. The etching stage 104 has an etching observation window 105 and is equipped with a gas pressure gauge 107. The RPS inlet / outlet water inlets 106 are controlled by the RPS control stage 300 to regulate the flow rate of cooling water. The etching stage 104 is used to perform thin film etching on materials such as silicon wafers and wafers. The gas pressure gauge 107 monitors the internal pressure of the etching stage 104, and the RPS stage is used for regulation. The remote plasma source 100 is also equipped with an equipment status display screen 102, which is used to observe the operating status, such as power, voltage, and current.

[0041] The gas ionization detection device 200 includes a gas dissociation circuit control device (maintenance gas input control module) for maintaining gas input, which is connected to the dissociation chamber of the remote plasma source 100 and is used to control the amount of maintenance gas input to the dissociation chamber. The gas ionization detection device 200 is also equipped with a sampling gas pressure gauge 108 to ensure an ultra-low pressure test environment of 100 mTorr and to ensure the accuracy of residual gas quantity acquisition. The gas ionization detection device 200 also includes an output detection unit, which is connected to the dissociation chamber through an ionized gas sample collection pipeline 202 and is used to detect the amount of residual maintenance gas in the gas in the dissociation chamber. The gas ionization detection device 200 also includes an output calculation unit, which is connected to the maintenance gas input gas dissociation circuit control device and the output detection unit and is used to calculate the ionization rate based on the amount of maintenance gas input to the dissociation chamber and the amount of residual maintenance gas in the gas output to the dissociation chamber.

[0042] The gas ionization detection device 200 detects the amount M of residual gas in the dissociation chamber and the amount N of input maintenance gas, respectively, and the dissociation rate is 1-M / N. In the remote plasma engineering process, nitrogen trifluoride (NF3) is decomposed into nitrogen and fluorine atoms when it is ionized by plasma. The fluorine atoms perform thin film etching on the silicon wafer. When the amount M of residual NF3 gas is less than the residual gas threshold, it means that there is not enough NF3 waste gas. Since NF3 is toxic, the etching station 104 can be opened to remove the silicon wafer. The furnace of the tail gas treatment device also stops working at this time to increase the power application efficiency. When the amount M of residual NF3 gas is greater than or equal to the residual gas threshold, it means that the process gas ionization process has not ended and the silicon wafer is continuously etched. The furnace of the tail gas treatment device also needs to work continuously.

[0043] Fourier transform infrared spectrometer 201 is used to collect infrared spectral data of the remaining maintenance gas. The spectrometer is connected to the etching stage 104 through the ionized gas sample acquisition pipeline 202 to sample the spectral data of the remaining maintenance gas in the dissociation chamber. The spectrometer exhaust gas output pipeline 203 is connected to the exhaust gas transmission pipeline, and the exhaust gas is output to the exhaust gas treatment device by the vacuum pump 500.

[0044] The RPS control station 300 is equipped with a gas flow meter, a pressure gauge, a water flow meter, a station display screen 301, and station status indicator lights 302. The gas flow meter, pressure gauge, and water flow meter are used to detect the inlet gas flow, cavity pressure, and cooling water flow of the remote plasma source 100. The RPS control station 300 is used to control the process gas flow, vacuum pressure, and water cooling system of the remote plasma source 100, including displaying parameters such as equipment operating status, power, voltage, and current, as well as recording fault information and modifying process parameters. Specifically, the gas flow meter controls the gas flow entering the RPS, working in conjunction with the vacuum pump 500 to achieve different power outputs of the RPS, simulating actual operating conditions.

[0045] The function diagram on the RPS test station display screen 301 is as follows: Figure 4 As shown, the test platform control module includes a process gas module, a vacuum pressure module, a water cooling module, a parameter display module, a fault information recording module, and a process parameter module. The process gas module can control the flow rate of the input gas and read it in real time, and work with the vacuum pump 500 to achieve different power outputs of the RPS to simulate actual operating conditions. The vacuum pressure module can control the pressure in the RPS cavity and the Fourier transform infrared spectrometer 201 by setting the pressure value and read it in real time. The water cooling module provides water cooling for the plasma source and can control the inlet and outlet water flow rates and read them in real time.

[0046] The parameter display module can read the actual power value, bus current and voltage, and equipment operating status from the RPS. First, the power switch is turned on, process gas is introduced, and the power value is set. Then, it checks whether the "Initialization Status (Ready)" and "Power Input (AC OK)" indicator lights are constantly on. "Initialization Status (Ready)" indicates that the equipment initialization status is normal; "Power Input (AC OK)" indicates that the power input is within the allowable range. Next, the ignition switch is pressed. "Ignition Status (Plasma ON)" indicates that the equipment has successfully ignited or is processing process gas; otherwise, it indicates that the equipment is not igniting or has failed to ignite. A constantly lit "Equipment Alarm (Fault)" light indicates that an alarm has occurred; otherwise, there is no alarm.

[0047] The fault information recording module allows users to view faults sent by the device, including the time of occurrence, type of fault, and number of occurrences of the current fault type. Fault types include: over-temperature alarm (OT), over-power alarm (OP), abnormal input voltage (ACV), output current drop (LC), output current exceeding limit (OC), and water leakage alarm. The process parameter module allows users to select either ignition process or burn-in aging process to test RPS.

[0048] The detection device is also designed with real-time monitoring capabilities, enabling immediate feedback on the plasma dissociation state. Real-time monitoring allows for timely adjustments to the plasma source's operating conditions, ensuring the stability and consistency of the production process.

[0049] The host computer system 400 is used to perform dissociation rate detection steps such as preprocessing, feature extraction, and pattern recognition on Fourier transform infrared spectral data.

[0050] The exhaust gas treatment equipment 600 is a system for treating various process waste gases on site. It is equipped with an exhaust gas treatment equipment inlet 601 and an exhaust gas treatment equipment inlet 602. The exhaust gas treatment equipment inlet 601 is connected to the outlet of the vacuum pump 500 through a pipeline. The inlet of the vacuum pump 500 is connected to the dissociation chamber through the exhaust gas transmission pipeline 501. The vacuum pump 500 ensures a low-pressure environment in the reaction chamber. Under low pressure, the collisions between gas molecules are reduced, which makes it more effective to excite gas molecules during plasma treatment. It also promotes the stable generation and maintenance of plasma and removes pollutants from the exhaust gas before it is introduced into the exhaust gas treatment equipment 600.

[0051] Among them, such as Figure 5 As shown, the dissociation rate detection method in this embodiment adopts a traditional method, such as...

[0052] S1. Near-infrared spectra of remote plasma source 100 with different dissociation rates are collected by Fourier transform infrared spectrometer 201; gas ionization detection device 200 detects the amount M of residual gas in the gas of dissociation chamber and the amount N of input maintenance gas respectively, then the dissociation rate is 1-M / N.

[0053] S2. A dataset of 100 ionization rates for a remote plasma source was established using near-infrared spectral data with different dissociation rates.

[0054] S3. Using the same near-infrared spectral acquisition conditions, sample the near-infrared spectrum of the plasma source to be detected, compare the measured characteristic spectral peak with the ionization dataset, determine the current residual gas (NF3) concentration, and then the dissociation rate is 1 - residual gas (NF3) concentration.

[0055] This device employs infrared mass spectrometry analysis and detection technology, enabling high-precision and high-sensitivity measurement of various active particles in plasma. This allows for accurate calculation of the dissociation rate, providing reliable data for plasma source performance evaluation. Furthermore, by applying near-infrared spectral data with different dissociation rates under varying pressures, flow rates, and temperatures, an ionization rate dataset is established. Characteristic spectral peaks are identified based on the detected residual NF3 gas quantity, and compared with the ionization rate dataset, enabling real-time detection of gas dissociation rates under different pressures, flow rates, and temperatures.

[0056] This testing device integrates an automated control system, infrared mass spectrometry analysis, and an RPS exhaust gas treatment system. Through the automated control system coordinating the operation of various functional modules, it can automatically complete the detection of relevant RPS technical indicators. This device achieves reliable testing of the RPS dissociation rate and simulates actual RPS operating conditions, eliminating the need for RPS testing on actual integrated circuit manufacturing equipment, resulting in low cost and short cycle time. The testing device realizes full-process monitoring and closed-loop control of the plasma source's operating status, improving the accuracy of dissociation rate detection and process stability.

[0057] Example 2:

[0058] like Figure 6-7 As shown, an electrothermal adsorption-type exhaust gas treatment device for a remote plasma source dissociation rate testing apparatus includes a control system and a gas content detection system, as well as a heating system, a steam injection system, a cooling system, and an adsorption system (neutralization tower) connected in sequence. A particle collection tank is also installed at the outlet of the steam injection system to collect solid particles (such as CaF2 precipitate) generated during the reaction, preventing pipe blockage and extending the equipment's service life. A heat exchanger is installed between the outlet of the steam injection system and the inlet of the heating system to recover waste heat from the exhaust gas to preheat the intake gas, raising the intake gas temperature to 300°C through waste heat recovery and reducing the energy consumption of the heating system. The inlet of the heating system is connected to the vacuum pump of the remote plasma source dissociation rate testing apparatus.

[0059] The heating system employs a three-section coaxial nested nickel-based alloy reaction tube (Inconel 600), with a length ratio of 1:2:1 (corresponding to the preheating section, main decomposition section, and deep pyrolysis section). The temperature gradient is 500℃ (preheating section) → 800℃ (main decomposition section) → 1000℃ (deep pyrolysis section). The inner wall is coated with a 200 μm thick Al2O3 ceramic layer (purity ≥99.5%), which is resistant to fluorine corrosion. A high-frequency induction coil (copper tube diameter 8 mm, turn spacing 5 mm) is wound around the outer wall of each section. The output power (0~20kW) is controlled by an independent frequency converter (frequency 50-100kHz), achieving precise adjustment of the temperature gradient.

[0060] High-frequency induction heating technology is adopted: the reaction tube wall is directly heated by the electromagnetic eddy current effect, with a heating rate of up to 50℃ / s, which saves 30% energy compared with traditional electric anode heating.

[0061] The steam injection system consists of a steam injection ring (made of 316L stainless steel, with an orifice diameter of 0.5 mm) installed at the outlet of the deep pyrolysis section. The injection rate of ultrapure steam is controlled by a mass flow meter (MFC), dynamically matched to the molar ratio of NF3 (range 0.8:1~1.2:1). This dynamic matching of the steam-NF3 molar ratio (0.8:1~1.2:1) ensures that F2 is fully converted to HF, reducing the risk of secondary pollution from byproducts. The decomposition of NF3 requires high-temperature pyrolysis or catalytic hydrolysis, typically represented by the chemical equation: 2NF3 + 3H2O → 6HF + NO + NO2. In this reaction, steam acts as a hydrolysis medium, providing hydroxyl groups (-OH) to accelerate the breaking of NF bonds. If the steam is insufficient (molar ratio below 0.8:1), NF3 may not decompose completely, and residual NF3 will be emitted as toxic gases. If the steam is excessive (above 1.2:1), it may dilute the reaction system, reduce reaction efficiency, or even inhibit the decomposition reaction due to localized temperature drops.

[0062] The cooling system is used to cool the mixed gas. The cooling temperature is determined by the pipe length and water flow rate, and it is generally cooled to 500±50℃.

[0063] The adsorption system is a neutralization absorption tower with a two-stage series design. The first-stage tower is filled with Ca(OH)₂ particles (3-5 mm in diameter) for initial adsorption of HF. The second-stage tower is equipped with a pH-feedback circulating spray system (Ca(OH)₂ solution concentration 10 wt%), with a spray rate of 5 L / min. By using the circulating spray of Ca(OH)₂ solution, HF is fixed as CaF₂ precipitate, achieving a fluoride content of <1 ppm in the tail gas.

[0064] The gas content detection system includes several NF3 detectors and an electrochemical HF sensor. The control system operates these systems according to a pre-set program. By monitoring the NF3 and HF concentrations in real time, the heating power and steam flow rate are dynamically adjusted to ensure that the exhaust gas treatment meets the standards (NF3 decomposition rate > 99%, HF < 1 ppm), adapting to high-concentration shock load conditions.

[0065] The exhaust gas treatment equipment in this embodiment 1 adopts the aforementioned electrothermal adsorption type exhaust gas treatment equipment, which includes thermal oxidation decomposition and reagent adsorption processes. The waste gas generated in the process is decomposed at high temperature by a heating system, and then discharged to the plant treatment system after dry adsorption treatment. The high-temperature system (400~1200℃) generated by the heating furnace decomposes and oxidizes the toxic NF3 gas that has not been dissociated in the upstream equipment at high temperature, turning the toxic gas into non-toxic reactants. After being cooled by a cooling system, the gas is then subjected to active chemical adsorption or reaction to generate deposited substances, achieving complete absorption of toxic and corrosive gases. The treated harmless gas then enters the plant exhaust system.

[0066] like Figure 8 As shown in the figure, this embodiment also provides a flowchart of the electrothermal adsorption type exhaust gas treatment device, the main process of which is as follows:

[0067] S1. Heating System: The system uses a three-stage independently temperature-controlled nickel-based alloy reaction tube (lined with ALO and ceramic coating to prevent oxidation of fluorine atoms F, which would reduce its lifespan). The temperature gradient is 500℃ (preheating stage) → 800℃ (main decomposition stage) → 1000℃ (deep pyrolysis stage), ensuring that NF is decomposed into NF3 and F2 step by step, thus improving the decomposition efficiency of NF3.

[0068] Each of the three independent temperature control sections is equipped with an NF3 detector, which detects the NF3 concentration (n vol%) of the input gas and the flow rate (lm) during the preheating stage. 3 / h, if the concentration n is less than the first concentration threshold N1 and the flow rate l is less than the flow rate threshold L, the preheating section is set to a furnace temperature of 500℃ (heating rate 30℃ / s, power 8 kW). (2) Main decomposition section: 800℃ (constant temperature accuracy ±5℃, power 15 kW), when the NF3 concentration is less than the second concentration threshold N2, it enters the deep pyrolysis stage, otherwise it continues heating. (3) Deep pyrolysis section: 1000℃ (power 18 kW, residence time ≥2 s), when the NF3 concentration is less than the third concentration threshold N3, it enters the steam injection system;

[0069] When the NF3 concentration (n vol%) of the input gas is detected during the preheating stage, and the flow rate is lm... 3If the concentration n is greater than or equal to the first concentration threshold N1, i.e., the heating system detects an increase in concentration within 0.5 s, the system automatically adjusts, raising the temperature of the main decomposition section to 850℃ and increasing the power to 20 kW. Furthermore, when the NF3 gas flow rate l is greater than or equal to the flow rate threshold L, the inlet gas velocity is reduced by 15% through the inlet valve, extending the residence time in the preheating stage. When the NF3 concentration is less than the second concentration threshold N2, the system enters the deep pyrolysis stage; otherwise, heating continues. Deep pyrolysis stage: 1000℃ (power 18 kW, residence time ≥ 2 s). When the NF3 concentration is less than the third concentration threshold N3, the system enters the steam injection system and simultaneously increases the steam flow rate to km. 3 / h (molar ratio 1.05:1).

[0070] S2, In-situ Neutralization System:

[0071] When the NF3 concentration (n vol%) of the input gas is detected during the preheating stage, and the flow rate (l km) is... 3 / h, if the concentration n is greater than or equal to the first concentration threshold N1, or when the NF3 gas flow rate l is greater than or equal to the flow rate threshold L, the water vapor injection system needs to synchronously increase the water vapor flow rate by km. 3 / h.

[0072] Water vapor injection system: Inject ultrapure water vapor (flow rate to NF3 molar ratio 1:1) at the end of the reactor to convert F2 into HF gas. The reaction formula is: 2F2 + 2H2O → 4HF + O2.

[0073] Multi-stage alkaline adsorption system: The neutralization absorption tower adopts a two-stage series design. The first-stage tower is filled with Ca(OH)₂ particles (3-5 mm in diameter) for initial adsorption of HF. The second-stage tower is equipped with a pH-feedback circulating spray system (Ca(OH)₂ solution concentration 10 wt%), with a spray rate of 5 L / min. The pH value of the spray liquid is monitored in real time, and the Ca(OH)₂ solution concentration (10 wt%) is adjusted to ensure HF neutralization efficiency (HF concentration in the tail gas <1 ppm) while preventing scaling in the adsorption tower. The circulating spray of Ca(OH)₂ solution fixes HF as CaF₂ precipitate, achieving a fluoride content in the tail gas <1 ppm. After passing through the adsorption system, if the NF₃ concentration is less than the fourth concentration threshold N₄ as monitored by an NF₃ detector, it is discharged into the plant system; otherwise, it is recirculated into the multi-stage alkaline adsorption system by a gas pump. Since NO and NO# can be absorbed by calcium hydroxide solution when mixed in a 1:1 ratio to produce calcium nitrite and water, and nitrogen dioxide can react directly with calcium hydroxide to produce calcium nitrate and calcium nitrite, nitrogen oxides in the exhaust gas can be treated together with Ca(OH)2 solution.

[0074] S3. Waste heat recovery and intelligent control:

[0075] The heat exchanger exchanges heat with the 1000℃ exhaust gas in a counter-current manner with the intake gas, raising the NF3 intake temperature from 25℃ to 300±10℃. By recovering the waste heat of the 1000℃ exhaust gas through the heat exchanger and preheating the intake port to 300℃, energy consumption can be reduced.

[0076] Dynamic control is achieved using a gas sensor (NF3 detector + electrochemical HF sensor): the NF3 concentration is monitored in real time by the gas sensor, and the heating power and the inlet gas flow rate are adaptively adjusted to ensure a stable decomposition rate.

[0077] Example 1 of the above-mentioned electro-adsorption exhaust gas treatment equipment working scenario: Standard operating condition treatment:

[0078] A. Operating parameters: Input gas: NF3 concentration 10 vol%, flow rate 12 m³ / s. 3 / h, O2 is used as the carrier gas (accounting for 90%).

[0079] Temperature control: (1) Preheating section: 500℃ (heating rate 30℃ / s, power 8 kW). (2) Main decomposition section: 800℃ (temperature control accuracy ±5℃, power 15 kW). (3) Deep pyrolysis section: 1000℃ (power 18 kW, residence time ≥2 s).

[0080] B. Neutralization system: Water vapor flow rate 6 m³ / h 3 / h, Ca(OH)2 solution spraying rate 8 L / min.

[0081] C. Performance Results: (1) Decomposition Efficiency: NF3 decomposition rate 99.7% (residual NF3 concentration <50ppm as determined by FTIR spectroscopy). (2) Byproduct Control: F2 conversion rate >99.9%, HF concentration in tail gas <0.5ppm (compliant with GB16297-1996 standard). (3) CaF2 precipitate purity at the outlet of the secondary absorption tower ≥98%, which can be directly recycled as industrial raw material. (4) Energy Consumption: Comprehensive power consumption 1.2 kWh / m³ 3 NF3 saves 52% more energy than traditional incineration methods.

[0082] Example 2 of the above-mentioned electro-adsorption exhaust gas treatment equipment working scenario: Treatment of high-concentration NF3 shock load:

[0083] A. Operating parameters: Input gas: NF3 concentration 30 vol%, flow rate suddenly increases to 20 m³ / h 3 / h (simulates abnormal operating conditions in the process).

[0084] B. Dynamic Response: The heating system detects an increase in concentration within 0.5 seconds and automatically adjusts: the main decomposition section temperature is raised to 850℃, and the power is increased to 20kW. The steam flow rate is simultaneously increased to 10m³ / h. 3 / h (molar ratio 1.05:1). The intake airflow rate is reduced by 15%, and the residence time is extended to 3s.

[0085] C. Performance results: (1) Decomposition efficiency: NF3 decomposition rate 99.6%, no F2 leakage (sensor alarm threshold 0.1 ppm). (2) System stability: temperature fluctuation < ±10℃, neutralization tower pH value maintained at 8.5-9.0 (avoiding Ca(OH)2 scaling).

[0086] The key process verification data for the above-mentioned work scenarios, Examples 1 and 2, are shown in Table 1 below:

[0087]

[0088] Special case handling:

[0089] This electrothermal adsorption type exhaust gas treatment equipment also includes an emergency pressure relief valve located between the air inlet of the heating system and the inlet of the adsorption system. When the air inlet pressure increases, the emergency pressure relief valve will open, and the exhaust gas will flow through a bypass pipeline to the adsorption tank to prevent back pressure buildup at the downstream end.

[0090] This exhaust gas treatment device achieves the step-by-step decomposition of NF3 through segmented heating, combined with a multi-stage adsorption system for efficient neutralization of harmful gases (such as HF), effectively removing harmful substances from exhaust gas and reducing environmental pollution. Its principle is as follows:

[0091] Preheating section: Gradually raises the temperature of the exhaust gas to the initial reaction temperature to prevent uneven reaction or incomplete decomposition due to sudden high temperature. Preheating also reduces thermal stress damage to the equipment.

[0092] Main decomposition stage: The temperature is raised to the optimal decomposition temperature of 800℃. At this temperature, the chemical bonds of NF3, namely the NF bonds, are more easily broken, generating N2 and F2 through thermal decomposition or catalytic reaction, or further transforming into stable products such as HF. This stage ensures that most of NF3 decomposes rapidly.

[0093] Deep pyrolysis section: Maintain a temperature of 1000℃ or slightly higher than the main reaction zone, extend the residence time to completely decompose residual NF3, prevent byproducts from recombinizing, and inhibit the reverse reaction of F2.

[0094] The decomposition of NF3 is an endothermic reaction, and high temperatures favor shifting the thermodynamic equilibrium towards the products. However, maintaining high temperatures throughout the process significantly increases energy consumption. Furthermore, consistently high temperatures may lead to side reactions, such as the formation of NO. xOr other fluorides. Staged temperature control optimizes the reaction pathway, ensuring that NF3 preferentially decomposes into target products such as N2 and F2 / HF, reducing harmful byproducts. Through three-stage temperature gradient control, the furnace achieves precise regulation of the NF3 decomposition process, balancing reaction rate, completeness, and energy efficiency, ultimately increasing the NF3 decomposition rate to over 99.5%, effectively reducing emissions of this potent greenhouse gas.

[0095] Example 3:

[0096] Figure 9 The diagram shows a traditional structure of the water-cooled duct at the air outlet. Figure 9 In this diagram, L represents the length of the water pipe, l represents the inner diameter of the cooling water channel, d represents the inner diameter of the water pipe, and D represents the outer diameter of the water pipe. Increasing the length of the cooling water pipe may mean a longer cooling time, leading to a decrease in the temperature of the plasma region. If the temperature is too low, it may hinder the dissociation reaction, potentially reducing the dissociation rate by 20%-30%, as gas dissociation requires sufficiently high temperatures and energy. Conversely, if the water pipe is too short, cooling is insufficient, or the temperature is too high, it may damage the equipment or cause the reaction to run away from control, interfering with the stability of the dissociation reaction.

[0097] Larger diameter water pipes allow for greater water flow, improving cooling efficiency and thus removing heat and lowering the temperature more quickly. However, an excessively large diameter can reduce flow velocity, affecting turbulence and reducing heat exchange efficiency. Conversely, while smaller diameters increase flow velocity, they can lead to excessive pressure drop, increased pump load, or even poor cooling performance due to insufficient flow.

[0098] In remote plasma testing systems, the design of the outlet water-cooled pipe directly affects the stability of plasma temperature and free radical distribution, thus impacting the accuracy of dissociation rate measurement. A pipe that is too short will result in insufficient heat dissipation, leading to increased outlet temperature, accelerated free radical recombination, and a lower dissociation rate measurement. Conversely, a pipe that is too long will increase flow resistance and pressure drop ΔP, requiring higher pump power and potentially causing localized boiling due to excessive coolant temperature rise, thus disrupting temperature uniformity.

[0099] Figure 10 This embodiment shows an optimized structural diagram of the outlet water-cooled pipe 103 of a remote plasma source dissociation rate testing device. The structure of the outlet water-cooled pipe has been improved by dividing it into multiple segments with progressively decreasing diameters. Each segment has its own pipe length L, pipe diameter D, and inner diameter l of the cooling water channel 1031. Specifically:

[0100] S1: Determine the heat dissipation requirements of the water-cooled pipes through thermodynamic calculations to avoid interference from local temperature fluctuations on the plasma dissociation state.

[0101] Calculate the heat load at the plasma outlet based on the plasma source power, gas velocity, and gas type (e.g., NF3 / Ar mixture). Q Heat load formula: Q = P · η ,in P For input power, η Energy conversion efficiency. Temperature change. Further calculations can be performed using gas parameters: Where m is the mass flow rate of the gas, and C m The isobaric specific heat capacity of the gas mixture is determined by the gas type and mixing ratio. Deionized water or ethylene glycol solution is selected as the coolant, and the flow rate is set. V (L / min) and cooling water temperature rise T in Typically, the temperature rise between the inlet and outlet water is controlled between 10 and 20°C to prevent vaporization or affect heat dissipation efficiency; ensure the coolant temperature rise Δ T Controlled within a reasonable range, where Δ T ≤5℃.

[0102] Traffic can be represented as ,in ρ Where is the density of the coolant, C p This is the specific heat capacity of water (approximately 4186 J / (kg·℃)).

[0103] S2: By controlling the pipe length, heat dissipation efficiency and flow resistance are balanced, and the interference of temperature gradient on dissociation rate measurement is avoided.

[0104] Pipe length L , k The thermal conductivity of the pipe material. K Let K be a proportionality coefficient, and K be an empirical constant, typically ranging from 0.8 to 1.2. Then, the length of the outlet cooling pipe can be expressed as:

[0105] (1);

[0106] The length L of the air outlet cooling pipe can be composed of the lengths L1, L2, and Ln of the first, second, and nth water pipe segments. n In other words, that is:

[0107] (2);

[0108] S3: Within the allowable ΔP range, optimize the design by adjusting the length L or diameter D. If the pressure loss is too high, the pipe diameter needs to be increased or the length shortened.

[0109] The target water flow velocity v should be controlled between 1 and 3 m / s to avoid excessive turbulence leading to high pressure loss or laminar flow causing poor heat dissipation in the water pipes. (Based on the flow rate formula...) The diameter of the water pipe can be preliminarily deduced as follows:

[0110] (3);

[0111] Among them, D1, D2, D n Represents the diameters of the first, second, and nth segments of the water pipe; Q1, Q2, Q n This represents the heat load at the plasma outlet in the first, second, and nth segments of the water pipe;

[0112] The relationship between pipe length L and pressure drop ΔP can be used to optimize the calculation of pipe lengths for each section. According to the Darcy-Weisbach formula:

[0113] (4);

[0114] in, f The coefficient of friction, f It is related to the Reynolds number Re and the pipe wall roughness. For water at 20°C, the relationship is as follows: .

[0115] If the relationship Re < 2000 exists in laminar flow, then f =64 / Re; The inner diameter of the i-th waterway segment can be expressed as:

[0116] (5);

[0117] If P is greater than the first pressure drop threshold P1 set for flow resistance, that is, the pressure loss ΔP is too high at this time, the pipe diameter needs to be increased or the length shortened to optimize the current i-th segment of the water pipe; the following equation can be derived from equation (4):

[0118] (6);

[0119] Therefore, the optimized pipe diameter and length are expressed as equations (7) and (8):

[0120] (7);

[0121] (8);

[0122] By accurately matching the parameters of each pipe section based on thermodynamic and fluid mechanics formulas, the coolant temperature rise ΔT ≤ 5℃ is ensured, the plasma dissociation temperature is kept stable, and the dissociation rate measurement error is reduced.

[0123] The temperature at the far-field plasma outlet is the highest, and the temperature decreases sequentially as it moves further away from the outlet. To address the excessively high outlet temperature, the water pipe near the outlet is designed with increased pipe diameter D and decreased inner channel diameter l to increase channel density. Figure 9 Compared with traditional water pipe design schemes, this embodiment adopts a water cooling temperature gradient adjustment method, and designs suitable length L, diameter D and water channel inner diameter l according to different water pipe sections, thereby improving the heat dissipation efficiency of remote plasma water cooling.

[0124] This outlet cooling water pipe structure balances heat dissipation efficiency and flow resistance through a variable diameter design, ensuring that heat dissipation requirements match the flow pressure drop, avoiding local boiling or insufficient cooling, and maintaining the temperature stability of the plasma dissociation reaction. This outlet cooling water pipe structure solves the problem of free radical recombination caused by excessively high local temperatures at the outlet, improves the accuracy of dissociation rate measurement, and enhances heat dissipation efficiency.

[0125] To verify the heat dissipation efficiency of the remote plasma source cooling system, it is necessary to quantify the impact of different waterway parameters on temperature gradient control through multiple sets of comparative experiments.

[0126] Example 1 is a three-section cooling water pipe design, with the following variable parameters set: cooling water pipe inner diameter 4.2cm, total cooling water pipe length... L It is 20.0cm; the diameter of the air outlet section is 20.0cm. D 1 is 12.3cm, length L 1=8.2cm, inner diameter of the first section of water channel l 1 is 1.5cm; middle section diameter D 2 is 8.3cm, length L 2 = 6.7cm, inner diameter of the second waterway l 2 is 2.0 cm; diameter of the final section D 3 is 6.0cm, length L 3 = 5.1cm, inner diameter of the third waterway l 3 is 2.5cm;

[0127] Example 2 is a design for a 5-segment cooling water pipe. The variable parameters are set as follows: the inner diameter of the cooling water pipe is 4.2 cm, and the total length of the cooling water pipe is... L It is 20cm; the diameter of the air outlet section is 20cm. D 1 is 15.2cm, length L 1 = 6.0 cm, inner diameter of the first waterway section l 1 is 1.0 cm; the diameter of the second section of the water pipe D 2 is 12.1cm, length L 2 = 5.0 cm, inner diameter of the second waterway l 2 is 1.2cm; middle section diameter D 3 is 10.0cm, lengthL 3 = 4.0 cm, inner diameter of the third waterway l 3 is 1.5cm; the diameter of the fourth section of the water pipe D 4 is 8.1cm, length L 4 = 3.0 cm, inner diameter of the 4th waterway l 4 is 1.7cm; diameter of the final segment D 5 is 6.0cm, length L 5 = 2.0 cm, inner diameter of the 5th waterway l 5 is 2.0cm;

[0128] The control group consisted of traditional cooling water pipes, with the following variable parameter: inner diameter of the cooling water pipe. d It is 4.2cm in diameter and has an outer diameter of 4.2cm. D It is 6.1cm, and the total length of the cooling water pipe is... L The diameter is 20.0 cm, and the inner diameter l of the cooling water channel is 2.5 cm;

[0129] The remote plasma source was preheated to full power to a steady state and maintained for 10 minutes before ignition and shutdown. Cooling water circulation was started and the water flow rate was kept at 5 L / min. After 30 seconds, the temperature of the remote plasma source outlet, the middle section temperature, and the cooling water outlet temperature were recorded using an infrared thermal imager. The experiment was repeated 3 times and the average value was taken, as shown in Table 2 below.

[0130]

[0131] Compared with Example 1, Example 2 shows that the 5-segment gradient water channel, through its refined segmented design, outperforms the 3-segment gradient water pipe in terms of temperature control at the air outlet, middle section, and end. The addition of two high-density water channels at the air outlet reduces local thermal resistance and significantly reduces temperature. The refined segmentation of the 5-segment gradient cooling structure makes the temperature gradient in the middle section gentler. At the end of the water channel, the 5-segment gradient cooling structure, with its longer cooling section, reduces residual heat accumulation and achieves higher cooling efficiency.

[0132] Compared to traditional water pipe structures, the gradient cooling structure reduces the highest temperature zone at the air outlet from 525℃ to 384℃, meeting the heat load control requirements of semiconductor processes; this is achieved through gradient adjustment of water channel parameters. D , L , l This increased the rate of temperature drop from the outlet to the end by 40%, verifying the effectiveness of the temperature gradient design.

[0133] Example 4:

[0134] In remote plasma systems, scaling, blockage, or micro-leakage in the outlet water pipe can directly affect heat dissipation efficiency, gas dissociation stability, and even lead to safety accidents. This embodiment presents a fault diagnosis method for the outlet water pipe of a remote plasma source, combining multiphysics sensing technology, data analysis, and intelligent algorithms to achieve real-time perception and early warning. Figure 11 As shown, it includes the following steps:

[0135] S1: The flow resistance pressure drop ΔP is monitored in real time by differential pressure sensors installed at the inlet and outlet of the air outlet water pipe, and local temperature distribution data ΔT is collected by an infrared thermal imager outside the wall of the air outlet water pipe. At the same time, a capacitive humidity sensor is arranged near the air outlet water pipe to monitor changes in ambient humidity ΔR.

[0136] S2: Based on the Kalman filter algorithm, the ΔP, ΔT, and ΔR data are fused to eliminate noise interference and obtain the state estimates of pressure drop, temperature, and humidity ΔP(k), T(k), and R(k).

[0137] S3: Construct the scaling / clogging objective function M and the leakage objective function N;

[0138] The mean of all decision trees is used as the final output to fit the scaling, clogging, and microleakage formed by each combination of process parameters, and the importance relationship between scaling, clogging, and microleakage and each process parameter is evaluated.

[0139] S4: Assign the importance of each process parameter to the weighting of differential pressure, flow rate, temperature, and humidity in the objective functions M and N for scaling, clogging, and micro-leakage, respectively. When M exceeds the first threshold M1, it is determined to be scaling; when it exceeds the second threshold M2, it is determined to be clogging; when N exceeds the leakage threshold N1, it is determined to be micro-leakage. M1 / M2 / N1 are all set values ​​and are adjusted according to actual conditions.

[0140] The following are the key steps and technical solutions for functional design:

[0141] The detection of scale and blockage in water pipes is as follows:

[0142] Scale forms when minerals from hard water adhere to the inner walls of water pipes under high temperatures and prolonged exposure. Blockage occurs because the continuous accumulation of scale gradually reduces the flow area of ​​the water pipes.

[0143] High-precision differential pressure sensors with an accuracy of ±0.1% FS are installed at the inlet and outlet of the water pipe. Scale or blockage will increase local flow resistance and reduce the differential pressure Δ. P A significant increase. Set the initial pressure differential to... P 0 kPa, if Δ P Continues to rise to the first differential pressure threshold PA pressure drop of 1 kPa triggers an alarm indicating excessive flow resistance and pressure drop. A non-invasive flow velocity measurement method is used, and the water flow rate is calculated based on the time difference of sound wave propagation. v The water flow velocity abnormally dropped to the flow threshold. v 1. If the flow rate drops from 10 L / min to 7 L / min, an abnormal flow alarm will be triggered. An infrared thermal imager is installed on the outside of the pipe wall. Due to poor thermal conductivity, scale-covered areas will form localized high-temperature points. When Δ... T A temperature difference greater than 10°C can be identified when the local high temperature point exceeds the temperature threshold. T At 1 o'clock, an over-temperature alarm was triggered.

[0144] The micro-leakage detection of the water pipe is as follows:

[0145] A capacitive humidity sensor is placed near the air outlet to detect abnormal increases in ambient humidity, with an initial humidity of [value missing]. R 0RH, if the humidity suddenly rises to the humidity threshold R If the humidity level reaches 1RH, an alarm for abnormal water pipe humidity will be triggered. Furthermore, the rate of decrease in water flow velocity and pressure differential within the pipes also reflects the presence of minor leaks. Using a differential pressure sensor, the rate of pressure decrease within the pipes is monitored after the water pump is shut off; normally it is <0.1 bar / min, while during a leak it is >0.5 bar / min. Similarly, the water flow velocity will also decrease appropriately during minor leaks, and a non-invasive flow velocity measurement method can be used.

[0146] To achieve real-time sensing and early warning, this embodiment uses the Kalman filter algorithm to fuse multi-source data such as pressure difference, flow rate, temperature, and humidity to eliminate noise interference, and infers the status of water pipes through observation data.

[0147] Kalman filtering involves two parts: prediction and update. It adjusts the weights of the predicted and observed values ​​by updating the Kalman gain to make the result closer to the true value. The steps are as follows:

[0148] S1: System state equations:

[0149] Establish the system's state equations, which describe how the system's current state is determined by its previous states and external inputs. This can typically be represented in the form of a linear dynamic system. x ( k ) = Ax ( k- 1) + Bu ( k ) + w ( k ),in x ( k ) indicates that the system at time t k The state;

[0150] A yes n *n State transition matrix, B It is the input control matrix. u ( k ) is a moment k Input, w ( k () is system process noise. x ( k () represents the data value at the current moment. x ( k- 1) This is the data value from the previous moment. The data value includes multi-source data such as differential pressure, flow rate, temperature, and humidity.

[0151] S2: Observation equation:

[0152] Establish observation equations to describe how to obtain observations by measuring the system; these are usually linear relationships. y ( k ) = Hx ( k ) + v ( k ),in y ( k ) indicates at time k The observed values, H It is the observation matrix. v ( k ) represents observation noise.

[0153] S3: Prediction Steps:

[0154] In Kalman filtering, a prediction step is first performed, using the system state equation and prior information to estimate the current state and state uncertainty of the system. The uncertainty equation is as follows:

[0155] (9);

[0156] (10);

[0157] In the formula, P - ( k )for k The prior estimate of the covariance matrix at time t; P - ( k -1) is k Prior estimate of the covariance matrix at time -1; Q Let be the covariance matrix of the prediction error.

[0158] S4: Update steps:

[0159] The next step is to update the state, comparing the predicted state with the actual observation, and using Kalman gain to correct the predicted value to obtain an estimate that is closer to the true state.

[0160] The three update equations are as follows:

[0161] (11);

[0162] In the formula, R The covariance matrix of the observation errors; K ( k )for k Kalman gain at time step;

[0163] (12);

[0164] (13);

[0165] In the formula P ( k )for k The covariance matrix at time t; I It is an identity matrix.

[0166] S5: Continuous iteration:

[0167] Finally, by continuously repeating the prediction and update steps, the estimation of the system state is gradually optimized over time, ultimately yielding highly accurate state estimates Δ for pressure difference, flow rate, temperature, and humidity. P ( k ), v ( k ), T ( k ), R ( k ).

[0168] S6: Fault type determination:

[0169] First, determine whether the system has triggered alarms such as excessive flow resistance and pressure drop, abnormal flow, over-temperature, or abnormal humidity. When an alarm command is issued, the system needs to be stopped for inspection and fault type determination.

[0170] Establish objective functions for scaling and clogging respectively. M Objective function for leakage faults N :

[0171] The relationship between the importance of scaling and clogging fault characteristics and various process parameters is as follows:

[0172] 1) Pressure differential (λ1): Scale buildup or blockage can lead to mineral accumulation on the inner wall of the pipe, increasing flow resistance and thus increasing the system's pressure differential. Since the pressure differential reflects the resistance to gas flow in the system, the increased flow resistance caused by scale buildup will directly increase the pressure differential;

[0173] 2) Flow rate (λ2): Scaling or blockage affects the flow path and reduces the effective flow area of ​​the pipeline, thus leading to a decrease in gas flow rate;

[0174] 3) Temperature (λ3): Reduced flow due to scaling or blockage can lead to poor heat dissipation and cause local temperature rise;

[0175] 4) Humidity (λ4): The humidity sensor is installed at the RPS outlet and does not reflect the effects of scaling and clogging; therefore:

[0176] (14);

[0177] The relationship between the importance of micro-leakage fault characteristics and various process parameters is as follows:

[0178] 1) Pressure difference (λ1): When a small leak occurs in the water pipe, the leak will cause the pressure difference before and after the leak point to increase;

[0179] 2) Flow rate (λ2): Micro-leakage will reduce the flow rate in the water pipe, resulting in a decrease in downstream flow rate;

[0180] 3) Humidity (λ4): The humidity sensor is installed at the RPS outlet and can accurately detect the degree of water pipe leakage; therefore:

[0181] (15);

[0182] In equation (14 / 15), t ( k (This refers to the current time.) t ( k- 1) is the previous time step, Δ P ( k ), v ( k ), T ( k ), R ( k ) represents the current state estimates of pressure difference, flow rate, temperature, and humidity, Δ P ( k- 1) v ( k -1) T ( k -1) R ( k-1) represents the estimated values ​​of pressure difference, flow rate, temperature, and humidity at the previous moment. λ 1. λ 2. λ λ1 represents the weighting of differential pressure, flow rate, and temperature, respectively; λ4 represents the weighting of humidity, where λ4 > λ1 and λ2. The weighting coefficients λ1 to λ4 are obtained based on historical fault data and are dynamically adjusted with the pipeline's service life.

[0183] when M Greater than the first fault threshold M At time 1, it is determined that scale buildup has occurred in the water pipes; when M Greater than the second fault threshold M At 2 o'clock, among them M 2> M If 1, it can be determined that there is a partial blockage in the water pipe at this time;

[0184] when N Greater than the leakage fault threshold N At time 1, it was determined that a minor leak had occurred in the water pipe.

[0185] This method for diagnosing gas outlet pipeline faults achieves accurate identification of scaling, blockage, and leakage (accuracy ≥ 95%) by integrating multi-sensor collaborative monitoring (differential pressure, temperature, humidity) with Kalman filter data, and reduces the false alarm rate to below 5%.

[0186] Weighting of pressure difference, flow rate, temperature, and humidity λ 1-4 The assessment of importance relationships is further explained as follows:

[0187] like Figure 12-13 As shown, the random forest regression algorithm evaluates the importance relationship between scaling, clogging, and micro-leakage and process parameters. The steps are as follows:

[0188] Step P1: Bootstrap Sampling:

[0189] A linear regression model can be used to fit the approximate linear relationship between scaling, clogging, and micro-leakage and various process parameters. T subsets {D1, D2, ..., D...} are drawn with replacement from the original dataset D. T}, where each subset has a sample size of N. The probability P(N) of each sample being selected in a single sampling is:

[0190] (16);

[0191] The samples that were not selected constitute the out-of-bag (OOB) dataset, which is used for error estimation and feature importance analysis.

[0192] Step P2: Decision Tree Construction:

[0193] Features are randomly selected, and the total number of features is M. t For each subset D t Construct a regression decision tree h t (x), when a node splits, m features are randomly selected (m≤M). t ).

[0194] The objective of node splitting in a regression tree is to minimize the mean squared error (MSE). For feature j and splitting threshold R... R (j,s), select the optimal split pair (j∗,s∗):

[0195] (17);

[0196] Among them, the actual threshold y for scaling and clogging faults i The actual threshold y of the micro-leakage fault is represented by the objective function M. i Represented by the objective function N; R L With R R c represents the left and right child node sample sets after the split. L and c R These are the predicted values ​​for the left and right child nodes, respectively. That is, the target mean of the subset samples:

[0197] (18);

[0198] Step P3: Integration of prediction results:

[0199] The final output is obtained by using the average prediction of all decision trees. Ensemble learning is used to reduce the uncertainty of predictions from individual trees, and the final output is as follows:

[0200] (19);

[0201] in, This is the average result; h t (x) represents the prediction result of a single decision tree; T represents the number of decision trees.

[0202] Step P4: Model performance evaluation metrics:

[0203] The root mean square error (RMSE) metric is used to quantify the accuracy of predicting scaling, clogging, and micro-leakage, respectively.

[0204] (20);

[0205] Determine whether the root mean square error of scaling, blockage, and micro-leakage and process parameters meets the error accuracy requirement of 0.1; otherwise, return to step P1 to continue iterating until the maximum number of iterations is reached.

[0206] Step P5: Feature Importance Assessment Analysis

[0207] Feature importance is measured by the change in out-of-bag (OOB) error after permuting the feature value. After randomly permuting feature Xj, its importance is measured by the change in OOB error. If the error increases significantly after permutation, it indicates that the feature has a significant impact on model prediction. The importance is calculated as follows:

[0208] (twenty one);

[0209] Among them, MSE t Let be the OOB error of the t-th tree.

[0210] Accordingly, the scores for assessing the importance of scaling, clogging, and microleakage in relation to process parameters are ranked as follows: Figure 14 As shown, the importance relationships between scaling and clogging faults and differential pressure, flow rate, and temperature are 0.51, 0.30, and 0.19, respectively, and these values ​​are assigned to the weights of differential pressure, flow rate, and temperature in the objective function M for scaling and clogging. Similarly, the importance relationships between microleakage and humidity, flow rate, and differential pressure are 0.83, 0.10, and 0.07, respectively. Therefore, the weights of humidity, flow rate, and differential pressure in the objective function M for microleakage can be obtained.

[0211] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0212] 1. This testing device integrates an advanced automated control system, which can automatically complete the testing process.

[0213] 2. This device uses infrared mass spectrometry analysis and detection technology, which can achieve high-precision and high-sensitivity measurement of various active particles in plasma, thereby accurately calculating the dissociation rate and providing reliable data for the performance evaluation of plasma sources.

[0214] 3. The device is designed with real-time monitoring capabilities, enabling immediate feedback on the plasma dissociation state. Real-time monitoring allows for timely adjustments to the plasma source's operating conditions, ensuring the stability and consistency of the production process.

[0215] 4. The RPS device is designed with a variable circulation heat dissipation device at the air outlet to solve the problem of temperature imbalance affecting the reliability of dissociation rate measurement.

[0216] 5. The detection device is designed with an exhaust gas treatment device that can effectively remove harmful substances from the exhaust gas and reduce environmental pollution.

[0217] 6. This remote plasma source dissociation rate assessment does not require testing on actual integrated circuit manufacturing equipment, resulting in low cost and short cycle time.

[0218] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An electrothermal adsorption type exhaust gas treatment device for RPS dissociation rate testing, characterized in that, include: The system comprises a heating system, a steam injection system, a cooling system, and an adsorption system connected in sequence. The heating system includes a segmented reaction tube, which is a three-section coaxial nested structure comprising a preheating section, a main decomposition section, and a deep pyrolysis section. Each section is independently temperature-controlled and heated by a high-frequency induction coil. The temperature field of the segmented reaction tube increases progressively from the inlet to the outlet, with the preheating section at 500°C, the main decomposition section at 800°C, and the deep pyrolysis section at 1000°C. The steam injection system is a ring-shaped injection device, with the injection rate of ultrapure steam controlled by a mass flow meter and dynamically matched to the molar ratio of NF3. The adsorption system includes a primary solid adsorption layer and a secondary circulating spray system. The primary solid adsorption layer is filled with Ca(OH)2 particles, and the secondary circulating spray system is equipped with a pH feedback device for dynamically adjusting the concentration and flow rate of the spray solution.

2. The electrothermal adsorption type exhaust gas treatment equipment according to claim 1, characterized in that: A heat exchanger is provided between the outlet of the steam injection system and the inlet of the heating system to recover waste heat from the exhaust gas and preheat the intake gas.

3. The electrothermal adsorption type exhaust gas treatment equipment according to claim 1, characterized in that: The outlet of the steam jet system is also equipped with a particle collection tank for capturing solid particles generated during the reaction.

4. The electrothermal adsorption type exhaust gas treatment equipment according to claim 1, characterized in that: An emergency pressure relief valve is provided between the air inlet of the heating system and the inlet of the adsorption system, which is used to release pressure when the pressure exceeds the limit.

5. The electrothermal adsorption type exhaust gas treatment equipment according to claim 1, characterized in that: It also includes a gas content detection system, which includes an NF3 detector and an HF sensor, used to monitor the concentration of NF3 and HF in the exhaust gas in real time and feed it back to the control system to adjust the heating power and water vapor injection amount.

Images