Method and system for on-line monitoring of early damage and abnormal operation of high-temperature quartz furnace tube

Abstract

The present application relates to a kind of high-temperature quartz furnace tube early damage and operation anomaly online monitoring method and system, comprising: real-time acquisition quartz furnace tube temperature and process flow state;When the temperature of quartz furnace tube is at furnace tube working temperature, and process flow state is at heat preservation stage, switch to active monitoring mode: to one end of quartz furnace tube apply ultrasonic sweep excitation signal, in the other end of quartz furnace tube acquisition ultrasonic response signal, based on ultrasonic response signal and the high-temperature health benchmark signal stored in system initialization stage are compared, and calculate damage factor, based on damage factor exceeds damage threshold value determine early damage;When process flow state is at loading and unloading stage, switch to passive monitoring mode: listen to acoustic emission signal in furnace tube, based on the amplitude of acoustic emission signal exceeds dynamic amplitude threshold value determine process anomaly.The present application solves the deficiency of periodic preventive replacement, the defect of shutdown manual visual inspection and the problem of dynamic anomaly monitoring loss.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of online monitoring technology of semiconductor and photovoltaic manufacturing equipment, and in particular to an early damage and operation anomaly online monitoring method and system for high-temperature quartz furnace tube. BACKGROUND

[0002] As a core process equipment for semiconductor and photovoltaic manufacturing, the quartz furnace tube needs to be operated at an extreme high temperature of 1000-1200℃ for a long time and bear huge thermal stress generated by frequent thermal cycles. The brittle nature of quartz material causes microcracks to be easily generated under thermal stress gradient, and these cracks continue to expand in thermal cycles, eventually causing sudden rupture of the furnace tube, resulting in equipment scrap, production line downtime, and contamination of the entire batch of wafers or solar cells, with a single economic loss of up to one million yuan. In addition, dynamic anomalies in the process (such as “boat sliding” impact on the inner wall of the furnace tube due to mechanical failure of the quartz boat loaded with wafers) will directly form crack sources or accelerate the expansion of existing damage, further shortening the service life of the furnace tube.

[0003] The current industry monitoring and maintenance methods have the following significant defects:

[0004] Shortcomings of regular preventive replacement: The furnace tube is replaced based on a fixed cycle (such as every six months), ignoring actual working condition differences. This results in waste of resources due to early replacement of healthy furnace tubes, and prominent safety hazards due to failure to timely warn damaged furnace tubes.

[0005] Defects of manual visual inspection during downtime: The inspection needs to be performed after the furnace tube is cooled to room temperature, which takes several hours and results in loss of production capacity. Manual inspection can only identify macroscopic surface cracks and is completely ineffective for early internal microcracks. The results depend on personnel experience and lack objective quantitative standards.

[0006] Lack of dynamic anomaly monitoring: There is no real-time monitoring capability for sudden process anomalies such as “boat sliding”. Usually, only after the wafer is damaged or the impact mark on the furnace tube is found can the anomaly be traced back and inferred, which cannot be immediately intervened or traced back to optimize.

[0007] In summary, the existing technology has the core defects of non-real-time, non-continuous, inability to detect early internal damage, and inability to capture dynamic anomalies. There is an urgent need for a monitoring technology that can continuously operate in a high-temperature environment while capturing early internal damage and dynamic anomalies, to promote the transition of furnace tube maintenance from a passive experience mode to a proactive prediction mode. SUMMARY

[0008] Therefore, it is necessary to provide an early damage and operation anomaly online monitoring method and system for high-temperature quartz furnace tube to solve the problems of the shortcomings of regular preventive replacement, defects of manual visual inspection during downtime, and lack of dynamic anomaly monitoring.

[0009] The application provides a high-temperature quartz furnace tube early damage and operation anomaly online monitoring method, which comprises the following steps of:

[0010] Real-time acquisition of quartz furnace tube temperature and process flow state;

[0011] When the temperature of the quartz furnace tube is at the working temperature of the furnace tube, and the process flow state is at the heat preservation stage, the active monitoring mode is switched to: an ultrasonic sweep excitation signal is applied to one end of the quartz furnace tube, an ultrasonic response signal propagating through the quartz furnace tube is collected at the other end of the quartz furnace tube, the ultrasonic response signal is compared with the high-temperature health reference signal stored in the system initialization stage, a damage factor is calculated, and early damage is determined based on the damage factor exceeding the damage threshold.

[0012] When the process flow state is at the loading and unloading stage, the passive monitoring mode is switched to: the acoustic emission signal in the furnace tube is listened to, and the process anomaly is determined based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold.

[0013] In one of the embodiments, the comparison between the ultrasonic response signal and the high-temperature health reference signal stored in the system initialization stage, and the calculation of the damage factor, and the determination of early damage based on the damage factor exceeding the damage threshold, comprise the following steps of:

[0014] Performing fast Fourier transform to convert the ultrasonic response signal into a frequency domain response signal;

[0015] Comparing the frequency domain response signal with the health reference signal, calculating the normalized value of the energy difference in the key frequency band as the damage factor;

[0016] When the damage factor exceeds the damage threshold for a plurality of times in succession, it is determined that the quartz furnace tube has early damage.

[0017] In one of the embodiments, the determination of the process anomaly based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold comprises the following steps of:

[0018] Real-time analysis of the relative amplitude, energy and duration of the acoustic emission signal, the dynamic amplitude threshold is set to be a preset multiple higher than the average amplitude of the background noise, and the energy decay rate and duration characteristics of the acoustic emission signal are combined for multi-dimensional verification;

[0019] When the amplitude of the acoustic emission signal is detected to instantaneously break through the dynamic amplitude threshold, and the energy and duration determination conditions are met, the slipper abnormal event is determined.

[0020] The application further provides a high-temperature quartz furnace tube early damage and operation anomaly online monitoring system, which comprises the following steps of:

[0021] The excitation and sensing module comprises the following steps of:

[0022] A waveguide rod, one end of which is connected to the end of the furnace tube, and the other end of which is a low-temperature end;

[0023] A vibration exciter, which is installed at the low-temperature end of the waveguide rod, and is used to generate a sweep excitation signal;

[0024] A sensor, which is encapsulated at the low-temperature end of the other waveguide rod, and is used to collect an ultrasonic response signal and an acoustic emission signal;

[0025] A data acquisition and control module, which is used to drive the vibration exciter, and digitize the sensor signal;

[0026] An analysis and decision module, which comprises:

[0027] A mode switching unit, which automatically activates an active or passive monitoring mode according to the input furnace tube temperature and process flow state;

[0028] An active analysis unit, which is used to calculate a damage factor and determine early damage;

[0029] A passive analysis unit, which is configured to determine a process anomaly by the amplitude of the acoustic emission signal exceeding a dynamic amplitude threshold value.

[0030] In one of the embodiments, the waveguide rod is made of a high-temperature resistant material, and is used to achieve thermal isolation, so as to reduce the working temperature of the sensor to below a preset temperature, and one end of the waveguide rod is coupled to the end of the furnace tube.

[0031] In one of the embodiments, the waveguide rod is made of quartz material, one end of which has a split pipe clamp, and the waveguide rod is coupled to a tail pipe which is integrally formed with the furnace tube at the end of the quartz furnace tube through the split pipe clamp, and the part of the split pipe clamp which is connected to the waveguide rod is made of quartz material and is integrally formed with the waveguide rod.

[0032] In one of the embodiments, the active analysis unit is configured to: when calculating the damage factor, perform a fast Fourier transform to convert the real-time collected ultrasonic response signal into a frequency domain response spectrum, and compare it with a pre-stored healthy baseline signal, and output the damage factor through the normalized value of the energy difference in the key frequency band.

[0033] In one of the embodiments, the passive analysis unit is configured to: by analyzing the amplitude, energy and duration characteristics of the acoustic emission signal, set the dynamic amplitude threshold value to be a preset multiple of the average amplitude of the background noise; when the signal amplitude instantaneously breaks through the dynamic amplitude threshold value, identify a slipper abnormal event and trigger an alarm.

[0034] In one of the embodiments, the system further comprises a user terminal and an alarm module, which are used to display the furnace tube state, the damage factor value and the real-time waveform in a graphical interface in real time, and immediately issue an alarm and automatically record event data when damage or abnormality is detected.

[0035] In one embodiment, the data acquisition and control module has multi-channel cooperative working capability, can monitor multiple furnace tubes simultaneously, and is configured to generate a sweep excitation signal of 50 kHz to 200 kHz to drive the exciter to perform active monitoring.

[0036] The above high-temperature quartz furnace tube early damage and operation anomaly online monitoring method and system directly implement active monitoring in the high-temperature operation of the quartz furnace tube by judging the real-time temperature and process flow state of the quartz furnace tube, without the need for shutdown and cooling, eliminating the loss of production capacity; based on the damage factor quantitative calculation of the ultrasonic response signal, the internal microcracks of 0.1 mm level can be identified, overcoming the micro-defect missing detection limitation of artificial visual inspection; the acoustic emission signal is automatically monitored during the loading and unloading stage, the amplitude mutation detection is used to capture the "sliding boat" impact event in real time, filling the monitoring blank of the existing technology for sudden abnormalities; the active / passive mode is automatically switched according to the process stage, covering the whole life cycle of the furnace tube from heating to holding to cooling to loading and unloading, eliminating the blindness of the regular replacement strategy. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0038] Figure 1 The flow chart of the high-temperature quartz furnace tube early damage and operation anomaly online monitoring method of one embodiment of the present application;

[0039] Figure 2 The principle diagram of the high-temperature quartz furnace tube early damage and operation anomaly online monitoring method system of one embodiment of the present application;

[0040] Figure 3 The structure schematic diagram of the waveguide rod, exciter and split type pipe clamp of the present application;

[0041] Figure 4 The structure schematic diagram of the waveguide rod, sensor and split type pipe clamp of the present application;

[0042] Figure 5 The principle diagram of the high-temperature quartz furnace tube early damage and operation anomaly online monitoring method device of one embodiment of the present application;

[0043] Figure 6 The internal structure diagram of the computer equipment of one embodiment. DETAILED DESCRIPTION

[0044] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0045] Quartz furnace tubes are indispensable core process equipment in modern high-precision manufacturing, especially in the production lines of semiconductor integrated circuits and photovoltaic solar cells. In key processes such as chemical vapor deposition (CVD), high-temperature diffusion and oxidation, quartz furnace tubes provide an ultra-pure, stable and controllable high-temperature reaction environment. The success of these processes directly determines the yield and performance of the final product, so the structural integrity and operational stability of the quartz furnace tube are crucial. However, its working environment is extremely harsh. Quartz furnace tubes need to operate at extremely high temperatures of up to 1000°C or even 1200°C for a long time, and frequently experience severe thermal cycling with rapid heating and cooling. Although quartz material itself is resistant to high temperature, its inherent brittleness makes it particularly vulnerable under a huge thermal stress gradient. This repeated, uneven thermal expansion and contraction gradually accumulates stress inside the material, leading to material fatigue and the emergence of microscopic cracks that cannot be detected by the naked eye. These initial small defects become stress concentration points and rapidly expand in subsequent thermal cycles, ultimately leading to sudden and catastrophic rupture of the furnace tube without any warning. The consequences are extremely serious: first, the furnace tube itself, which is not cheap, is scrapped; second, the production line is forced to shut down, causing huge production losses; most fatally, the fragmentation of the furnace tube can instantly contaminate the high-purity production environment, causing the entire batch of valuable wafers or solar cells being processed in the cavity to be scrapped, resulting in economic losses of hundreds of thousands or even millions of yuan. In addition to the aging damage of the material itself, dynamic abnormalities in the production process also pose a serious threat to the furnace tube. In automated production, quartz boats (or "flower baskets") loaded with wafers need to be precisely pushed into and pulled out of the furnace tube. Due to mechanical tolerances, guide rail wear or control system errors, sometimes "boat slipping" occurs - the quartz boat is temporarily stuck during movement and then suddenly accelerates under the action of the pushing force, hitting the inner wall of the furnace tube or the front baffle. This abnormal impact not only can directly cause the fragile wafers to break, but also can cause local damage to the inner wall of the quartz furnace tube, forming new crack sources or exacerbating the expansion of existing micro-cracks, greatly shortening the safe service life of the furnace tube.

[0046] In the face of the above serious challenges, the current industry-wide maintenance and monitoring methods have significant defects and shortcomings and cannot effectively deal with these risks:

[0047] Periodic preventive replacement: This is the most common strategy, which sets a fixed service life (such as half a year or a year) for the furnace tube according to the recommendations of the equipment supplier or historical experience, and the furnace tube is replaced when the service life expires. This "one-size-fits-all" approach is essentially a blind operation based on probability, completely ignoring the actual working condition differences and health status of each furnace tube. The disadvantages are obvious: on the one hand, a large number of furnace tubes that can still be safely used are replaced prematurely, resulting in a huge waste of materials and an increase in costs; on the other hand, for furnace tubes with poor working conditions or occasional impacts, their damage may have developed to a dangerous level before the replacement cycle arrives, and this method cannot provide any risk warning, and the safety hazard still exists.

[0048] Shutdown manual visual inspection: This method requires the production line to be completely stopped, waiting for the furnace tube to naturally cool from thousands of degrees to room temperature (this process usually takes several hours or even longer), and then a visual inspection is performed by an experienced engineer or a simple endoscope is used for exploration. The defects of this method are as follows:

[0049] Low efficiency, affecting production capacity: Long shutdown and cooling waiting time seriously affects the continuity and production efficiency of the production line. Limited detection capability: manual visual inspection can only find large-sized surface cracks that have developed to the macro level, and is completely powerless for small cracks in the material interior that are in the early stage of development. This makes it a "stopgap" inspection rather than a "preventive" monitoring, and it does not have early warning capability; high subjectivity, dependent on experience: the detection result is highly dependent on the experience and responsibility of the inspector, and lacks objective and quantitative evaluation criteria, so the reliability cannot be guaranteed.

[0050] Lack of real-time monitoring of process abnormalities: For dynamic and occasional process abnormal events such as "sliding boats", there is almost no effective real-time online monitoring means in the existing technical system. Usually, only when the wafer is inspected later or the furnace tube is inspected during shutdown, can it be inferred that an abnormality may have occurred. This lag makes it impossible for the factory to intervene in time, trace the cause of the accident, or prevent the problem from happening again by optimizing process parameters or maintaining the robot.

[0051] In summary, the existing technology has a huge technical gap in the health and safety monitoring of high-temperature quartz furnace tubes, which is non-real-time, non-continuous, cannot detect early internal damage, and cannot capture dynamic process abnormalities. The industry urgently needs an intelligent monitoring technology that can achieve 7x24 hours online, real-time, early damage warning and process abnormality diagnosis, so as to change the passive, experience-based mode of furnace tube maintenance to a proactive, data-based predictive maintenance mode.

[0052] The purpose of the present application is to provide a multifunctional method and system integrating active damage monitoring and passive abnormal event monitoring, which can perform real-time online health assessment and process abnormal alarm on quartz furnace tubes in high temperature environment, so as to solve the pain points in the prior art.

[0053] The furnace tube temperature during the holding stage is usually 1000-1200 DEG C, and if the ultrasonic wave is used to detect the furnace tube, the following difficulties need to be solved:

[0054] The temperature resistance limit of the probe: the core material (such as lead zirconate titanate PZT) of the conventional piezoelectric ultrasonic probe and the working temperature are usually limited below 50-150 DEG C. The working upper limit of the high-temperature special probe (such as lithium niobate ) or electromagnetic acoustic transducer (EMAT) is usually in the range of 300-600 DEG C. The core working temperature of the quartz furnace tube is usually 800-1200 DEG C or even higher. The conventional probe cannot directly contact the tube wall at such a high temperature and will be damaged immediately.

[0055] Coupling agent failure: ultrasonic detection must have good acoustic coupling (medium) to effectively transmit acoustic energy from the probe to the measured object (quartz furnace tube). Water, oil or special coupling paste is the most commonly used coupling agent. At the high temperature of the furnace tube (much higher than the boiling point of water), any liquid coupling agent will evaporate, decompose or carbonize instantly, and cannot form an effective acoustic coupling layer. High-temperature solid coupling agent (such as special molten metal, ceramic powder) is extremely difficult to apply, has poor effect and may contaminate the furnace tube.

[0056] Therefore, in the key quartz furnace tube monitoring of the semiconductor, photovoltaic and other industries, acoustic emission (AE) has been widely used and verified. The advantages of acoustic emission (AE) are:

[0057] Non-contact high-temperature area: the sensor is installed on the low-temperature flange or support structure at both ends of the furnace tube, far away from the high-temperature area; no coupling agent is needed: the stress wave is transmitted through the structure; dynamic monitoring: the transient energy release of crack propagation is directly captured, which is an ideal means for early warning of failure; simple engineering implementation: the installation has little effect on the furnace body, and the cost is relatively controllable. Acoustic emission (AE) is often considered to be the most effective, most practical and most mature online crack monitoring technology. However, acoustic emission mainly detects dynamic cracks, and it is difficult to determine static cracks that already exist but do not expand, and background noise (such as mechanical vibration, fluid flow sound) may interfere with signal recognition, which requires complex signal processing technology.

[0058] The high-temperature quartz furnace tube early damage and operation abnormal online monitoring method and system of the present application will be described below. Figures 1-6

[0059] As Figure 1 ​As shown, in one embodiment, a high-temperature quartz furnace tube early damage and operation anomaly online monitoring method includes the following steps:

[0060] Step S110, real-time acquisition of quartz furnace tube temperature and process flow state.

[0061] In the system initialization phase, the active monitoring mode is executed when the process flow state is in the holding phase, the frequency domain response signal is acquired and stored as a health reference signal. After installing the system on a new furnace tube or a known healthy furnace tube, perform an active monitoring scan in a high-temperature (1000℃-1200℃) steady state, acquire the frequency domain response signal and store it as a health reference. Thus, by establishing a reliable health reference signal, an objective quantitative reference is provided for subsequent damage detection, avoiding the subjectivity and lag of manual visual inspection. The problem of missing reference in the prior art is solved, ensuring the accuracy and consistency of early damage identification, and laying the foundation for subsequent fully automatic monitoring, eliminating the risk of misjudgment due to experience dependence from the source.

[0062] Based on the real-time acquisition of the furnace tube temperature and the process flow state (such as the holding phase or the loading and unloading phase), the system automatically switches to the active monitoring mode or the passive monitoring mode.

[0063] Step S120, when the quartz furnace tube temperature is at the furnace tube working temperature (1000℃-1200℃) and the process flow state is in the holding phase, switch to the active monitoring mode: apply an ultrasonic sweep excitation signal to one end of the quartz furnace tube, collect the ultrasonic response signal propagating through the quartz furnace tube at the other end of the quartz furnace tube, compare the ultrasonic response signal with the high-temperature health reference signal stored in the system initialization phase, and calculate the damage factor, and determine early damage based on the damage factor exceeding the damage threshold.

[0064] Specifically, the ultrasonic sweep excitation signal with a frequency range of 50 kHz to 200 kHz is injected into the quartz furnace tube through the waveguide rod, the sweep excitation signal propagates along the inner wall of the quartz furnace tube in the form of circumferential guided wave to the other end of the quartz furnace tube, forming a guided wave mode around the tube wall, and a single excitation can cover the entire length of the furnace tube. If the excitation signal is injected into the quartz furnace tube (the initial injection angle can be selected to be 5-25°), the ultrasonic wave spirals along the tube wall, and a single excitation can cover the entire tube wall surface area, which helps to detect the damage (such as fine cracks) of the tube wall. After the excitation signal is injected, the reflected wave of the inner wall reflection (reflection angle = incidence angle) and the outer wall reflection (forming a folded path) is coherently superimposed to form a stable propagation mode, and the energy propagates along the circumferential direction of the tube wall. By limiting the sweep signal to a specific frequency band, the system can more accurately excite and capture ultrasonic guided waves in the active monitoring mode. The signal propagation efficiency is optimized, the sensitivity to fine cracks is enhanced, the frequency band covers the high sensitivity region of the quartz furnace tube material response, can effectively reduce noise interference, improve the accuracy of damage factor calculation, and thus more reliably identify early internal damage.

[0065] In practical applications, on the basis of 50 kHz to 200 kHz sweep excitation, the frequency band is further divided into three sensitive sub-frequency bands: low frequency band (50-80 kHz): for detecting deep cracks (depth >1 mm) in the furnace tube; medium frequency band (80-150 kHz): for capturing sub-surface micro-cracks (0.1-1 mm); high frequency band (150-200 kHz): for identifying surface damage (<0.1 mm).

[0066] The real-time collected frequency domain response signal is compared with the healthy benchmark signal, and the normalized value of the energy difference in the key frequency band is calculated as the damage factor (through signal energy attenuation, correlation coefficient change, etc. algorithms). If the damage factor calculation uses a weighted energy attenuation model:

[0067] ,

[0068] wherein, is the frequency domain amplitude of the healthy benchmark signal, is the frequency domain amplitude of the real-time collected signal, is the sub-frequency band weight coefficient (for example, =0.3, =0.5, =0.2), and the system performs sweep excitation every 30 minutes when the furnace tube is at 1200°C. For a furnace tube with a 0.2 mm micro-crack, the energy attenuation rate in the medium frequency band is 18.7%, and the DF is calculated to be 0.42 (threshold = 0.35), successfully triggering early warning.

[0069] The frequency domain response signal is obtained by Fourier transform of the ultrasonic response signal propagating through the furnace tube. Thus, a quantitative diagnostic criterion is provided, the influence of temperature and environmental changes is eliminated by normalization processing, and the objectivity and comparability of damage judgment are ensured. The problem of subjective experience dependence in the prior art is solved, early damage warning is more reliable, and data support is provided for maintenance decision-making. When the damage factor exceeds the damage threshold for multiple times in succession, it is determined that the furnace tube has early damage.

[0070] In step S130, when the process flow state is in the loading and unloading stage, the passive monitoring mode is switched to: listening to the acoustic emission signal in the furnace tube, and determining the process abnormality based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold.

[0071] Specifically, the relative amplitude, energy and duration of the acoustic emission signal are analyzed in real time, the dynamic amplitude threshold is set to be a preset multiple (such as 10 times) higher than the average amplitude of the background noise, and the energy decay rate and duration characteristics of the acoustic emission signal are combined for multi-dimensional verification. When the amplitude of the acoustic emission signal is detected to break through the dynamic amplitude threshold instantaneously and meets the energy and duration determination conditions, it is determined that the boat sliding abnormal event occurs. Thus, through adaptive threshold adjustment, the noise fluctuation in the production environment is adapted, the false positive rate is greatly reduced, and the sensitive capture of sudden events such as boat sliding is ensured. The reliability of abnormal detection is improved, false judgments caused by background noise changes are avoided, and the practicability of the system is enhanced.

[0072] In the high-temperature holding stage, the system performs periodic frequency sweeping excitation and signal acquisition (such as once every 30 minutes), and in the loading and unloading stage, the system switches to continuously listen to the acoustic emission signal. Thus, the coverage of the whole life cycle (heating, holding, cooling, loading and unloading) of the furnace tube is realized, no manual intervention is required, and the blindness of the existing regular replacement strategy and the production capacity loss problem caused by shutdown inspection are completely solved. Through intelligent mode switching, the system performs active damage detection in the key process stage (such as high-temperature operation), and performs passive abnormal listening in the dynamic process stage (such as quartz boat movement), which significantly improves the real-time and continuity of monitoring, optimizes the use of system resources, and ensures 7x24 hours unattended operation. The execution interval of the active monitoring mode is set to be once every 30 minutes, which balances the monitoring frequency and system resource consumption, avoids excessive monitoring leading to hardware burden, and ensures timely capture of damage evolution in the high-temperature holding stage, improving the efficiency and sustainability of the system.

[0073] In the active monitoring mode, the system calculates the damage factor (such as the normalized value of the energy difference in the key frequency band), and determines early damage when the damage factor exceeds the damage threshold; in the passive monitoring mode, the system analyzes the amplitude, energy and duration of the acoustic emission signal, and determines process abnormalities (such as boat slipping events) when the signal amplitude instantaneously breaks through the dynamic amplitude threshold. The high sensitivity identification of early internal damage and the real-time capture of dynamic abnormalities are realized. Specifically, based on the frequency domain analysis of the ultrasonic response signal, microcracks (including dynamic cracks and static cracks) of 0.1mm level can be detected, overcoming the limitations of manual visual inspection for microscopic defects; at the same time, through the dynamic threshold judgment of the acoustic emission signal, the monitoring blank of sudden events such as boat slipping in the prior art is filled, ensuring that the wafer can be warned at the moment of abnormality, preventing wafer contamination and equipment damage.

[0074] When determining early damage or process abnormalities, the system immediately triggers an alarm and automatically records the event time, furnace tube number and characteristic signal data (such as signal waveforms before and after triggering). This step solves the problem of response lag in the prior art through the immediate alarm mechanism, allowing the operator to quickly intervene and reduce production losses; the automatic recording function provides detailed event data for subsequent traceability analysis and process optimization, enhancing the reliability and traceability of the system.

[0075] In addition, the present application also provides an online monitoring system for early damage and operation abnormalities of high-temperature quartz furnace tubes.

[0076] As shown in Figure 2 , Figure 3 and Figure 4 , in one embodiment, a high-temperature quartz furnace tube damage and operation abnormality monitoring system includes an excitation and sensing module 210, a data acquisition and control module 220, and an analysis and decision module 230.

[0077] The excitation and sensing module 210 includes a waveguide rod 212, an exciter 214 and a sensor 216. One end of the waveguide rod 212 is connected to the end of the quartz furnace tube 50, and the other end is the low-temperature end. The waveguide rod 212 is made of high-temperature resistant material, which is used to realize thermal isolation, reduce the working temperature of the sensor to below the preset temperature (such as 50°C), and the waveguide rod 212 is coupled to the end of the quartz furnace tube 50 through a fixing device, and based on the acoustic impedance matching design to ensure efficient propagation of ultrasonic waves. As an option, the waveguide rod 212 is made of quartz material, one end of which has a split pipe clamp 218, and is coupled to the tail pipe (exhaust pipe or temperature measuring pipe) of the quartz furnace tube 50 through the split pipe clamp 218. The part of the split pipe clamp 218 connected to the waveguide rod 212 is made of quartz material and is integrally formed with the waveguide rod 212. The coupling part of the split pipe clamp and the quartz furnace tube 50 is padded with an ultra-thin (0.05-0.1mm) high-temperature ductile metal foil (such as gold, platinum, and indium foil). When the split pipe clamp 218 is locked on the tail pipe of the quartz furnace tube 50, the mechanical pressure flattens the micro voids, and the plastic deformation of the metal fills the interface, achieving better coupling effect. The waveguide rod 212 and the quartz furnace tube 50 are made of the same material and have similar expansion coefficients. When heated, the end of the waveguide rod expands, automatically increases the contact pressure, and improves the coupling.

[0078] When the waveguide rod 212 conducts the high temperature (such as 1070°C) of the end of the furnace tube to the low temperature end below 50°C, it makes the sensor out of the high temperature invalid zone, solves the problem that the sensor cannot work directly in high temperature environment, and realizes all-weather online monitoring. The flange type fixing device and the acoustic impedance matching design ensure that the ultrasonic energy is efficiently coupled to the furnace tube, improving the signal signal-to-noise ratio and damage detection sensitivity. The mechanical coupling design avoids the contact failure caused by high-temperature thermal expansion, ensures the efficient propagation of ultrasonic waves between the waveguide rod 212 and the quartz furnace tube 50 (energy loss <5%), solves the problem of signal attenuation in high temperature environment, and reduces the false detection rate. The exciter 214 is installed at the low-temperature end of one waveguide rod 212, which is used to generate a sweep excitation signal. The exciter 214 is a non-contact or coupled exciter such as an electromagnetic exciter (EMAT), which applies the sweep excitation signal to the quartz furnace tube 50 through the high-temperature resistant waveguide rod. The sensor 216 is packaged at the low-temperature end of the other waveguide rod 212, which is used to collect ultrasonic response signals and acoustic emission signals. The sensor 216 is a high-sensitivity sensor such as a piezoelectric ceramic sheet (PWAS), which is packaged at the low-temperature end of the waveguide rod 212 to receive the ultrasonic signals propagating through the furnace tube. The same high-sensitivity sensor receives the sweep response in active mode and captures the acoustic emission event in passive mode, realizing dual functions with single hardware, reducing system complexity.

[0079] The data acquisition and control module 220 is configured to drive the exciter 214 and digitize the sensor signals of the sensor 216. The module has multi-channel cooperative working capability, can monitor multiple furnace tubes at the same time, improves system efficiency, and is configured to generate a sweep excitation signal of 50 kHz to 200 kHz to drive the exciter to perform active monitoring. The sweep frequency range of 50 kHz to 200 kHz covers the sensitive frequency band of the quartz furnace tube, balances the penetration depth and resolution, and enhances the detection rate of micro-cracks.

[0080] The analysis and decision module 230 includes a mode switching unit, an active analysis unit, and a passive analysis unit.

[0081] The mode switching unit automatically activates the active or passive monitoring mode according to the input furnace tube temperature and process flow state. The furnace tube temperature is obtained in real time through an external temperature sensor. According to the preset temperature threshold and process flow state (such as heating, holding, cooling, loading and unloading), the working mode (active monitoring or passive monitoring) of the system is automatically switched.

[0082] The active analysis unit is configured to calculate the damage factor and judge the early damage. The active analysis unit is configured to: when calculating the damage factor, perform fast Fourier transform (FFT) to convert the real-time collected ultrasonic response signal into a frequency domain response spectrum, and compare it with the pre-stored healthy baseline signal, and output the damage factor through the normalized value of the energy difference in the key frequency band. Through FFT conversion of the frequency domain response spectrum, comparison with the healthy baseline signal, and output of the damage factor through the normalized value of the energy difference in the key frequency band, objective quantitative identification of micro-cracks (0.1 mm level) is realized. Frequency domain analysis filters environmental noise, avoids misjudgment caused by time domain signal fluctuations, and normalizes to eliminate the influence of temperature drift, ensuring the universality of the damage threshold criterion.

[0083] The passive analysis unit is configured to determine the process abnormality by the acoustic emission signal amplitude exceeding the dynamic amplitude threshold. The passive analysis unit is configured to: by analyzing the amplitude, energy and duration characteristics of the acoustic emission signal, set the dynamic amplitude threshold to be a preset multiple (such as 10 times) higher than the average amplitude of the background noise, adapt to environmental noise changes, reduce false alarm rate, and through multi-dimensional analysis of amplitude, energy and duration, instantaneously identify the slide boat impact characteristics (sudden high amplitude pulse), realize millisecond level response. When the signal amplitude instantaneously breaks through the dynamic amplitude threshold, the slide boat abnormal event is identified and an alarm is triggered.

[0084] In this embodiment, the high-temperature quartz furnace tube damage and operation anomaly monitoring system further comprises a user terminal and an alarm module, which is used to display the furnace tube state, damage factor value and real-time waveform in a graphical interface in real time, and immediately issue an alarm and automatically record event data when damage or anomaly is detected. The graphical interface displays the furnace tube state, damage factor value and waveform in real time, improves the operation intuitiveness, and the alarm module immediately alarms when damage or anomaly is triggered, shortens the fault response time. The event data (such as signal waveform before and after the alarm) is automatically recorded, which supports accident backtracking and root cause analysis.

[0085] In one embodiment, the present application describes a monitoring implementation applied to a high-temperature quartz furnace tube in a semiconductor diffusion process.

[0086] System hardware deployment:

[0087] The object to be measured is a horizontal quartz furnace tube with an outer diameter of about 200 mm, a length of about 3000 mm, and a working temperature of up to 1070℃. At both ends of the furnace tube, outside the heating zone in the normal temperature area, a set of excitation assembly and a set of sensing assembly are respectively installed, wherein the excitation assembly includes a waveguide rod and an excitation vibrator, and the sensing assembly includes a waveguide rod and a sensor. Each set of assembly contains a specially designed split type pipe clamp fixing device, which is designed through acoustic impedance matching to ensure good coupling with the end face of the quartz furnace tube. A high-temperature resistant waveguide rod with a length of 50 cm is tightly connected with the end face of the furnace tube through the fixing device. An electromagnetic excitation vibrator is installed at the cold end of the waveguide rod of the excitation assembly. A high-sensitivity piezoelectric sensor is packaged and fixed at the cold end of the waveguide rod of the sensing assembly. The design of the waveguide rod realizes effective thermal isolation from the high-temperature end of the furnace tube to the normal-temperature end of the sensor / excitation vibrator by using its length and low thermal conductivity, ensuring that the working temperature of the excitation vibrator and the sensor does not exceed 50℃. A K-type thermocouple is attached to the outer wall of the furnace tube for real-time monitoring of the furnace tube temperature. The excitation vibrator, the sensor and the thermocouple are connected to an integrated data acquisition and control module, which is responsible for signal generation, acquisition and preliminary processing, and is connected to the user terminal through Ethernet.

[0088] Implementation process of the monitoring method:

[0089] Step one: health benchmark establishment (offline or first installation)

[0090] A new, confirmed undamaged quartz furnace tube is installed on the equipment. The heating program is started to bring the furnace tube to and stabilize at the working temperature of 1070°C. At this time, the operator manually triggers a "baseline acquisition" through the user terminal. The data acquisition and control module drives the electromagnetic exciter to generate a linear sweep signal from 50 kHz to 200 kHz. The signal is transmitted into the quartz furnace tube through the waveguide rod, and after propagation in the furnace tube, it is received by the sensor at the other end. After the received time-domain signal is digitized, the system performs a fast Fourier transform (FFT) on it to obtain its frequency-domain response spectrum. This spectrum is saved as the "1070°C health baseline signal" of the furnace tube.

[0091] Step two: automatic active monitoring (damage detection)

[0092] In subsequent normal production, the system enters the fully automatic monitoring mode. When the furnace tube temperature feedback by the thermocouple enters and stabilizes in the high-temperature holding stage (for example, temperature > 900°C), the system automatically switches to the active monitoring mode.

[0093] a) Excitation and acquisition: the system automatically repeats the sweep excitation and signal acquisition process in step one at a preset interval of 30 minutes.

[0094] b) Feature extraction and analysis: the system compares the latest acquired signal frequency-domain response spectrum with the pre-stored "health baseline signal". A damage factor (DI) is calculated. In this embodiment, the damage factor is defined as the normalized value of the energy difference of the two spectra in the key frequency band (such as 80-150 kHz). When micro-cracks appear inside the furnace tube, the propagation path of the ultrasonic wave will change, the energy will scatter and attenuate, resulting in significant changes in the frequency energy distribution of the received signal, thereby increasing the DI value.

[0095] c) Diagnosis and alarm: the system has preset an alarm threshold, for example, DI > 0.3. When the calculated DI value exceeds the threshold, the status indicator light of the corresponding furnace tube on the user terminal interface changes from green to yellow, and a "early damage warning" prompt is popped up. If the DI value exceeds the threshold for 3 consecutive measurements, the system confirms damage and automatically records the relevant signal data.

[0096] Step three: automatic passive monitoring (boat sliding and other anomaly detection)

[0097] When the production process enters the quartz boat loading or unloading stage, the system automatically switches to the passive monitoring mode.

[0098] a) Listening and acquisition: the electromagnetic exciter stops working. The sensor and data acquisition module switch to high-sensitivity listening state and continuously acquire the acoustic emission signals on the furnace tube.

[0099] b) Feature analysis: the algorithm analyzes the relative amplitude and energy of the received signals in real time. Normally, the acoustic signals generated by the smooth movement of the quartz boat have low and stable amplitudes. When the "boat slip" phenomenon occurs, the sudden impact or friction of the quartz boat will generate a burst acoustic emission signal with extremely short time, energy and amplitude much higher than the background noise.

[0100] c) Diagnosis and alarm: the algorithm sets a dynamic amplitude threshold (for example, 10 times higher than the average amplitude of the background noise). Once the signal amplitude breaks through the threshold instantaneously, the system immediately determines that the "boat slip" anomaly has occurred. The user terminal immediately pops up a red alarm "Process anomaly: boat slip detected!" and records the time point of the event and the corresponding acoustic emission signal waveform for process personnel to analyze.

[0101] Through the above implementation, the present application successfully integrates active damage detection and passive abnormal event monitoring seamlessly in an automated system, achieving intelligent and multifunctional monitoring of the full life cycle and full workflow of high-temperature quartz furnace tubes.

[0102] Compared with the prior art, the present application has the following significant advantages:

[0103] Multi-functional monitoring combining active and passive methods is achieved: a set of system can not only detect static and slowly developing internal micro-cracks through active ultrasonic guided wave technology, but also capture dynamic and sudden process abnormal events (such as boat slip) through passive acoustic emission technology, with comprehensive functions.

[0104] Online real-time monitoring in high-temperature environment is achieved: the ingenious high-temperature waveguide rod design solves the worldwide problem that sensors cannot work in high-temperature areas, making it possible to monitor the furnace tube in working state 7x24 hours without interruption, with strong early warning capability.

[0105] Early damage identification capability is strong and sensitivity is high: based on the high sensitivity of ultrasonic guided waves to small changes in structure and the method of calculating damage factors through frequency domain analysis, early internal damage that cannot be detected by the naked eye can be effectively identified, preventing problems from occurring.

[0106] High automation and intelligence: the entire monitoring process, including mode switching, data acquisition, analysis and judgment, alarm recording, etc. is completely automatic and does not require human intervention, greatly reducing labor costs and eliminating the interference of subjective factors, with reliable results.

[0107] Improving process control level and product yield: real-time alarm of abnormal events such as "boat slip" helps process engineers optimize equipment parameters or robot actions in a timely manner, not only protecting the furnace tube, but also directly avoiding damage to the wafer, improving product yield.

[0108] The high-temperature quartz furnace tube damage and operation abnormality monitoring device provided by the application is described below, and the high-temperature quartz furnace tube damage and operation abnormality monitoring device described below can be correspondingly referred to the high-temperature quartz furnace tube damage and operation abnormality monitoring method described above.

[0109] As shown in Figure 5 In one embodiment, a high-temperature quartz furnace tube early damage and operation abnormality online monitoring device includes a real-time data acquisition module 510, an active monitoring switching module 520, and a passive monitoring switching module 530.

[0110] The real-time data acquisition module 510 is used to acquire the quartz furnace tube temperature and process flow state in real time.

[0111] The active monitoring switching module 520 switches to the active monitoring mode when the temperature of the quartz furnace tube is at the furnace tube working temperature and the process flow state is at the holding stage: an ultrasonic sweep excitation signal is applied to one end of the quartz furnace tube, an ultrasonic response signal propagating through the quartz furnace tube is collected at the other end of the quartz furnace tube, the ultrasonic response signal is compared with the high-temperature health reference signal stored in the system initialization stage, and the damage factor is calculated, and early damage is determined based on the damage factor exceeding the damage threshold.

[0112] The passive monitoring switching module 530 is used to switch to the passive monitoring mode when the process flow state is at the loading and unloading stage: listen to the acoustic emission signal in the furnace tube, and determine the process abnormality based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold.

[0113] Figure 6 An example of a schematic diagram of the physical structure of an electronic device, which can be a smart terminal, is shown in Figure 6 The electronic device includes a processor, a memory, and a network interface connected by a system bus. The processor of the electronic device is used to provide computing and control capabilities. The memory of the electronic device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the electronic device is used to communicate with external terminals through network connection. The computer program is executed by the processor to implement the high-temperature quartz furnace tube early damage and operation abnormality online monitoring method, which includes:

[0114] Acquire the quartz furnace tube temperature and process flow state in real time;

[0115] When the temperature of the quartz furnace tube is at the working temperature of the furnace tube and the process flow state is at the holding stage, switch to the active monitoring mode: apply an ultrasonic sweep excitation signal to one end of the quartz furnace tube, collect an ultrasonic response signal propagating through the quartz furnace tube at the other end of the quartz furnace tube, compare the ultrasonic response signal with the high-temperature health reference signal stored in the system initialization stage, and calculate a damage factor, and determine early damage based on the damage factor exceeding the damage threshold;

[0116] When the process flow state is at the loading and unloading stage, switch to the passive monitoring mode: listen to the acoustic emission signal in the furnace tube, and determine the process abnormality based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold.

[0117] Those skilled in the art can understand that, Figure 6 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the electronic device to which the scheme of the present application is applied. The specific electronic device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0118] In another aspect, the present application also provides a computer storage medium storing a computer program, which, when executed by a processor, implements the online monitoring method for early damage and operation abnormality of a high-temperature quartz furnace tube. The method comprises:

[0119] Real-time acquisition of the temperature of the quartz furnace tube and the process flow state;

[0120] When the temperature of the quartz furnace tube is at the working temperature of the furnace tube and the process flow state is at the holding stage, switch to the active monitoring mode: apply an ultrasonic sweep excitation signal to one end of the quartz furnace tube, collect an ultrasonic response signal propagating through the quartz furnace tube at the other end of the quartz furnace tube, compare the ultrasonic response signal with the high-temperature health reference signal stored in the system initialization stage, and calculate a damage factor, and determine early damage based on the damage factor exceeding the damage threshold;

[0121] When the process flow state is at the loading and unloading stage, switch to the passive monitoring mode: listen to the acoustic emission signal in the furnace tube, and determine the process abnormality based on the amplitude of the acoustic emission signal exceeding the dynamic amplitude threshold.

[0122] In yet another aspect, a computer program product or computer program is provided, which includes computer instructions stored in a computer readable storage medium. The processor of the electronic device reads the computer instructions from the computer readable storage medium. The processor executes the computer instructions to implement the online monitoring method for early damage and operation abnormality of a high-temperature quartz furnace tube. The method comprises:

[0123] Real-time acquisition of quartz furnace tube temperature and process flow state;

[0124] When the temperature of the quartz furnace tube is at the working temperature of the furnace tube, and the process flow state is at the heat preservation stage, switching to an active monitoring mode: applying an ultrasonic sweep excitation signal to one end of the quartz furnace tube, collecting an ultrasonic response signal propagating through the quartz furnace tube at the other end of the quartz furnace tube, comparing the ultrasonic response signal with a high-temperature health reference signal stored in the system initialization stage, and calculating a damage factor, determining early damage based on the damage factor exceeding a damage threshold;

[0125] When the process flow state is at the loading and unloading stage, switching to a passive monitoring mode: listening to acoustic emission signals in the furnace tube, and determining process abnormalities based on the amplitude of the acoustic emission signals exceeding a dynamic amplitude threshold.

[0126] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware, and the computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments of each method. In the embodiments of the present application, any reference to memory, storage, database or other medium can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory.

[0127] As an illustration but not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0128] Each technical feature of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of technical features in the above embodiments are described, however, as long as the combinations of technical features do not exist contradictory, they should be considered as the scope of the present application.

[0129] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for on-line monitoring of early damage and operational anomalies in high temperature quartz furnace tubes, characterized in that, The method comprises: real-time acquisition of quartz furnace tube temperature and process flow state; when the temperature of the quartz furnace tube is at the working temperature of the furnace tube and the process flow state is at the heat preservation stage, switching to an active monitoring mode: applying an ultrasonic sweep excitation signal to one end of the quartz furnace tube through a waveguide rod, collecting an ultrasonic response signal propagating through the quartz furnace tube at the other end of the quartz furnace tube through another waveguide rod, comparing the ultrasonic response signal with a high-temperature health reference signal stored in the system initialization stage, calculating a damage factor, and determining early damage based on the damage factor exceeding a damage threshold, wherein the waveguide rod is made of quartz material; when the process flow state is at the loading and unloading stage, switching to a passive monitoring mode: listening to acoustic emission signals in the furnace tube, and determining process abnormalities based on the amplitude of the acoustic emission signals exceeding a dynamic amplitude threshold; the comparison of the ultrasonic response signal with the high-temperature health reference signal stored in the system initialization stage and the calculation of the damage factor based on the damage factor exceeding the damage threshold to determine early damage, comprising: performing a fast Fourier transform to convert the ultrasonic response signal into a frequency domain response signal; comparing the frequency domain response signal with the health reference signal, calculating the normalized value of the energy difference in the key frequency band as the damage factor; when the damage factor exceeds the damage threshold for multiple times in succession, it is determined that the furnace tube has early damage.

2. The method of claim 1, wherein the method further comprises: the determination of process abnormalities based on the amplitude of the acoustic emission signals exceeding the dynamic amplitude threshold, comprising: real-time analysis of the relative amplitude, energy and duration of the acoustic emission signals, wherein the dynamic amplitude threshold is set to be a preset multiple higher than the average amplitude of the background noise, and the energy decay rate and duration characteristics of the acoustic emission signals are used for multi-dimensional verification; when the amplitude of the acoustic emission signal is detected to instantaneously break through the dynamic amplitude threshold and meets the energy and duration determination conditions, it is determined to be a slipper abnormal event.

3. A system for on-line monitoring of early damage and operational anomalies of a high-temperature quartz furnace tube, for implementing the method for on-line monitoring of early damage and operational anomalies of a high-temperature quartz furnace tube according to claim 1 or 2, characterized in that The system comprises: an excitation and sensing module, comprising: a waveguide rod connected to one end of the furnace tube and having a low-temperature end, wherein the waveguide rod is made of quartz material; a vibration exciter installed at the low-temperature end of one waveguide rod for generating a sweep excitation signal; a sensor packaged at the low-temperature end of the other waveguide rod for collecting ultrasonic response signals and acoustic emission signals; a data acquisition and control module for driving the vibration exciter and digitizing the sensor signals; an analysis and decision module, comprising: a mode switching unit for automatically activating the active or passive monitoring mode according to the input furnace tube temperature and process flow state; an active analysis unit for calculating the damage factor and determining early damage; a passive analysis unit configured to determine process abnormalities by the amplitude of the acoustic emission signals exceeding the dynamic amplitude threshold.

4. The on-line high-temperature quartz furnace tube early damage and operation anomaly monitoring system according to claim 3, characterized in that, The waveguide rod is made of high-temperature resistant material for thermal isolation, reducing the working temperature of the sensor to below the preset temperature, and one end of the waveguide rod is coupled to the end of the furnace tube.

5. The on-line high-temperature quartz furnace tube early damage and operation anomaly monitoring system according to claim 3, characterized in that, One end of the waveguide rod has a split pipe clamp, and the split pipe clamp is coupled to the tail pipe of the quartz furnace tube end which is integrally formed with the furnace tube, wherein the part of the split pipe clamp connected to the waveguide rod is made of quartz material and is integrally formed with the waveguide rod.

6. The on-line high-temperature quartz furnace tube early damage and operation anomaly monitoring system according to claim 3, characterized in that, The active analysis unit is configured to: when calculating the damage factor, perform a fast Fourier transform to convert the real-time collected ultrasonic response signal into a frequency domain response spectrum, and compare it with a pre-stored healthy baseline signal, and output the damage factor through the normalized value of the energy difference in the key frequency band.

7. The on-line high-temperature quartz furnace tube early damage and operation anomaly monitoring system of claim 3, wherein, The passive analysis unit is configured to: by analyzing the amplitude, energy and duration characteristics of the acoustic emission signal, set a dynamic amplitude threshold value as a preset multiple higher than the average amplitude of the background noise; when the signal amplitude instantaneously breaks through the dynamic amplitude threshold value, identify a sliding boat abnormal event and trigger an alarm.

8. The on-line high-temperature quartz furnace tube early damage and operation anomaly monitoring system of claim 3, wherein, The system further comprises a user terminal and an alarm module for real-time display of the furnace tube state, damage factor value and real-time waveform in a graphical interface, and immediately issues an alarm and automatically records event data when damage or abnormalities are detected.

9. The system for on-line monitoring of early damage and operational anomalies in high-temperature quartz furnace tubes according to any one of claims 3 to 8, characterized in that The data acquisition and control module has multi-channel cooperative working capability, can simultaneously monitor multiple furnace tubes, and is configured to generate a sweep excitation signal of 50 kHz to 200 kHz to drive the exciter to perform active monitoring.

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