A method and device for measuring pressure in a vacuum pipe of a single crystal furnace

Abstract

The present application relates to pressure detection technical field, specifically to a kind of single crystal furnace vacuum pipeline pressure measurement method and device.The method quantifies the temperature deviation of vacuum pipeline in crystal growth process;Temperature data and the growth rate of increasing trend are matched and analyzed, and the time delay amount of temperature data and growth rate is identified by matching section group;With the change of time delay amount of temperature data and growth rate in crystal growth process, and the relationship of the deviation change of pressure, the dynamic compensation of temperature lag is analyzed, and the delay compensation index is determined;After temperature data compensation is carried out according to delay compensation index and temperature deviation, current adjustment pressure measurement data is obtained.The present application analyzes the dynamic accompanying condition of temperature and crystal growth, determines time delay compensation by accompanying time delay degree, compensates temperature data in combination with temperature deviation, and adjusts pressure, so that the measured pressure data can more truly reflect the pressure condition in crystal growth process, and the precision of pressure measurement is improved.

Description

Technical Field

[0001] This invention relates to the field of pressure detection technology, specifically to a method and apparatus for measuring pressure in a vacuum pipeline of a single crystal furnace. Background Technology

[0002] A single crystal furnace is a device that melts polycrystalline materials such as polycrystalline silicon using a graphite heater in an inert gas environment (mainly nitrogen and helium) to grow dislocation-free single crystals using the Czochralski method. In the modern semiconductor and photovoltaic industries, the single crystal furnace is a key piece of equipment for producing high-quality single crystals, and the vacuum environment during its operation plays a decisive role in the crystal growth quality. The vacuum pipe, as a crucial channel for maintaining the vacuum state inside the single crystal furnace, requires precise pressure measurement. In the production of semiconductor-grade single crystal silicon, even extremely small pressure fluctuations can lead to crystal defects, affecting chip performance. Therefore, a method for real-time and accurate measurement of vacuum pipe pressure is needed to adjust vacuum system parameters promptly and ensure a stable crystal growth environment.

[0003] In existing technologies, direct measurement of pressure data within a vacuum pipeline is susceptible to errors due to variations in the ambient temperature. Temperature changes affect the thermal motion of gases, thereby altering their pressure characteristics and causing measurement deviations. Considering the physical process of crystal growth, temperature changes may not respond in real-time to the crystal growth rate, exhibiting a certain hysteresis effect. Discrepancies also exist between temperature changes and the crystal growth process. This leads to adjustment errors in directly measuring vacuum pipeline pressure through temperature adjustments, obscuring the true pipeline pressure data and consequently affecting the monitoring of the crystal growth process in the single-crystal furnace. Summary of the Invention

[0004] To address the technical problem in existing technologies where adjustment deviations occur during the direct measurement of vacuum pipeline pressure via temperature adjustment, thus obscuring the true pipeline pressure data, the present invention aims to provide a method and apparatus for measuring vacuum pipeline pressure in a single crystal furnace. The specific technical solution adopted is as follows:

[0005] This invention provides a method for measuring pressure in a vacuum pipe of a single crystal furnace, the method comprising:

[0006] During the crystal growth stage, temperature and pressure data are collected at each moment, and the crystal growth rate at each moment is obtained.

[0007] Based on the fluctuation deviation between the current temperature data and the reference temperature data, the temperature offset index for the current moment is obtained; in terms of time series, matching analysis is performed based on the correlation between the growth trend of temperature data and growth rate to obtain matching segment groups; the time delay of each matching segment group is obtained by the time deviation between temperature data and growth rate in the matching segment group; and the current temperature delay impact is obtained by combining the consistency of the growth trend between temperature data and growth rate in all matching segment groups and the instability of the time delay.

[0008] Based on the changes in the deviation between the pressure data and the reference pressure data at each moment in the time series, and the changes in the corresponding time delay at each moment, combined with the influence of temperature delay, the current delay compensation index is obtained.

[0009] By combining the current delay compensation index and temperature offset index, the current temperature data is adjusted to obtain temperature compensation data; the current adjustment pressure data is then determined using the temperature compensation data.

[0010] Furthermore, the method for obtaining the temperature offset index includes:

[0011] The difference between the current temperature data and the reference temperature data is used as the current temperature fluctuation; the ratio between the temperature fluctuation and the preset allowable fluctuation is used as the current temperature deviation index.

[0012] Furthermore, the method for obtaining the matching group includes:

[0013] Curve fitting is performed on temperature data and growth rate in time series to obtain temperature data curves and growth rate curves; the slope of temperature data curves and growth rate curves at each moment is calculated, and time periods with continuous positive slopes are taken as growth segments; the length of the growth segment is greater than the preset minimum time period length.

[0014] For any growth segment of the temperature data curve, the growth segment in the growth rate curve that is closest to the initial time of the growth segment is taken as the matching segment of the growth segment; and each growth segment and its corresponding matching segment form a pair as a matching segment group.

[0015] Furthermore, the method for obtaining the time delay includes:

[0016] In each matching segment group, the time difference between the initial moments of the two growth segments is used as the initial delay deviation value; the time difference between the final moments of the two growth segments is used as the final delay deviation value.

[0017] The average of the initial delay deviation value and the final delay deviation value is used as the time delay for each matching segment group.

[0018] Furthermore, the method for obtaining the temperature delay effect includes:

[0019] For any matching segment group, the temperature data curve and growth rate curve in the matching segment group are matched using the DTW algorithm to obtain matching pairs; the slope difference between the temperature data curve and the growth rate curve in each matching pair is calculated as the synchronization deviation degree of each matching pair; the sum of the synchronization deviation degrees of all matching pairs is used as the accompanying deviation index of the matching segment group; the mean of the accompanying deviation indices of all matching segment groups is used to obtain the synchronization growth deviation index.

[0020] The delay instability index is obtained by multiplying the mean of the time delay of all matched segments by the standard deviation of the time delay.

[0021] The product of the synchronous growth deviation index and the delay instability index is used as the temperature delay influence degree.

[0022] Furthermore, the method for obtaining the delay compensation index includes:

[0023] The difference between the pressure data at each moment and the reference pressure data is used as the pressure deviation at each moment; the ratio of the pressure deviation to the reference pressure data is used as the pressure error index at each moment.

[0024] Curve fitting was performed on the time delay and pressure error indicators respectively to obtain the time delay data curve and the pressure error curve.

[0025] The correlation between the time delay data curve and the pressure error curve is calculated and normalized to obtain the pressure delay influence degree; the product of the pressure delay influence degree and the temperature delay influence degree is used as the delay compensation index.

[0026] Furthermore, the method for acquiring the temperature compensation data includes:

[0027] The product of the delay compensation index and the temperature offset index is used as the temperature adjustment degree; the sum of the current temperature data and the temperature adjustment degree is used as the temperature compensation data.

[0028] Furthermore, the method for obtaining the adjustment pressure includes:

[0029] Substituting the temperature compensation data into the ideal gas equation, we obtain the adjusted pressure data.

[0030] Furthermore, the method for obtaining the growth rate includes:

[0031] Obtain the crystal mass increase, crystal density, and growth interface area at each time step;

[0032] The ratio of the increase in crystal mass to the growth time at each moment is taken as the mass growth rate; the product of crystal density and growth interface is negatively correlated and mapped as the influence of growth unit.

[0033] The product of the quality growth rate and the influence of the growth unit is used as the growth rate at each time step.

[0034] The present invention also provides a pressure measuring device for a vacuum pipeline of a single crystal furnace, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of a pressure measuring method for a vacuum pipeline of a single crystal furnace as described in any of the above claims.

[0035] The present invention has the following beneficial effects:

[0036] This invention quantifies the temperature offset effect in a vacuum pipeline during crystal growth, enabling real-time assessment of thermal field anomalies and providing precise input for compensation. It analyzes the dynamic growth of temperature data and growth rate, identifying the time delay between temperature data and growth rate through matching segment groups, thus clarifying the lag effect of temperature changes on the growth rate. By analyzing the relationship between the temperature data of the vacuum pipeline, the time delay of crystal growth rate, and pressure deviation during crystal growth, it analyzes the dynamic compensation for temperature lag, providing a degree of compensability based on the impact of the delay relationship on pressure measurement. Finally, after temperature data compensation based on compensation and offset indices, the current pressure measurement data is updated and adjusted, making the temperature-based adjustments more accurate. This invention analyzes the dynamic interaction between temperature and crystal growth, determines time delay compensation based on the degree of accompanying time delay, combines temperature offset compensation with pressure data adjustment, enabling the measured pressure data to more accurately reflect the pressure conditions during crystal growth and improving the accuracy of pressure measurement. Attached Figure Description

[0037] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 A flowchart of a method for measuring pressure in a vacuum pipeline of a single crystal furnace, provided in one embodiment of the present invention;

[0039] Figure 2 A schematic diagram of a temperature data curve and a growth rate curve provided in one embodiment of the present invention;

[0040] Figure 3 This is a schematic diagram of a time delay data curve and a pressure error curve provided in one embodiment of the present invention. Detailed Implementation

[0041] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a single crystal furnace vacuum pipeline pressure measurement method and apparatus proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0043] The following description, in conjunction with the accompanying drawings, details the specific scheme of the single crystal furnace vacuum pipeline pressure measurement method and device provided by the present invention.

[0044] Please see Figure 1 The diagram illustrates a flowchart of a method for measuring pressure in a vacuum pipe of a single crystal furnace according to an embodiment of the present invention. The method includes the following steps:

[0045] S1: During the crystal growth stage, temperature and pressure data are collected at each moment, and the crystal growth rate at each moment is obtained.

[0046] Pressure measurement in a vacuum pipeline is crucial to the quality of crystal growth, and the pressure measurement is closely related to real-time temperature changes. Therefore, during crystal growth in an ideal vacuum pipeline, obtaining corresponding reference temperature and reference pressure data is essential for analyzing actual testing.

[0047] Temperature probes are placed at key locations in the pipeline, such as sensor mounting points, exhaust ports, and process areas. Since the temperature varies at different locations within the vacuum pipeline, a weighted average temperature is calculated based on the temperature at each location, serving as the temperature data for each moment during monitoring. Similarly, pressure data is obtained for each moment.

[0048] It should be noted that by using a multi-sensor layout, such as thermocouples and infrared thermometers to monitor the temperature at key locations in real time, in the specific operation of this embodiment of the invention, the thermocouples need to be inserted into the melt to a depth of ≥30mm, the emissivity of the infrared thermometer is set to 0.9, and a blackbody radiation source is used for calibration weekly to ensure that the temperature data error is <±0.3℃, providing a reliable temperature input for subsequent pressure correction and avoiding systematic errors caused by inaccurate temperature measurement.

[0049] During crystal growth, temperature directly affects the melt viscosity, diffusion coefficient, and thermodynamic conditions of the solid-liquid interface. Different temperature gradients lead to different growth rates and crystal qualities. Growth rate typically refers to the length or volume of a crystal grown per unit time along a specific direction, such as axial or radial. For single-crystal growth, such as using the Czochralski method to grow single-crystal silicon, the growth rate can be determined by measuring the crystal pulling speed and diameter change.

[0050] Therefore, analyzing the relationship between temperature and growth rate requires understanding how temperature affects the kinetics of crystal growth, such as the attachment and diffusion of atoms or molecules at the solid-liquid interface. In this embodiment of the invention, during the single crystal growth process, the increase in crystal mass, crystal density, and growth interface area are obtained at each moment, and the growth rate is quantified using data from these various dimensions. The ratio of the increase in crystal mass to the growth time at each moment is used as the mass growth rate, reflecting the change in mass. A negative correlation is established between the product of crystal density and the growth interface area, which is used as the growth unit influence degree, reflecting the degree of influence of the attachment surface and density.

[0051] It should be noted that negative correlation mapping is a technique well known to those skilled in the art, such as using inverse proportional or negative exponential forms, and will not be elaborated or limited here.

[0052] The product of the quality growth rate and the influence of each growth unit is ultimately used as the growth rate at each time step. As an example, the expression for the growth rate is: ,in, Expressed as growth rate, Expressed as the increase in crystal mass, This represents the growth time corresponding to the increase in crystal mass. Crystal density, The area of ​​the growth boundary, This is expressed as the rate of increase in quality. This is expressed as the degree of influence per unit of growth.

[0053] S2: Based on the fluctuation deviation between the current temperature data and the reference temperature data, obtain the temperature offset index at the current moment; in terms of time series, perform matching analysis based on the correlation between the growth trend of temperature data and growth rate to obtain matching segment groups; through the time deviation between temperature data and growth rate in the matching segment groups, obtain the time delay of each matching segment group; combining the consistency of the growth trend between temperature data and growth rate in all matching segment groups, and the instability of the time delay, obtain the current temperature delay impact.

[0054] According to the ideal gas law PV=nRT, when the volume V and the quantity n of the substance remain constant, a change in temperature T will cause a linear change in pressure P. In the vacuum pipes of a single-crystal furnace, temperature fluctuations can be significant, ranging from room temperature to several hundred degrees Celsius. Directly acquiring pressure data under these conditions will result in deviations due to temperature variations. Furthermore, temperature changes affect gas expansion and pressure fluctuations at different growth stages. Therefore, real-time monitoring of temperature data is crucial to ensure accurate pressure control.

[0055] Because crystal growth is extremely sensitive to temperature gradients, even minute temperature fluctuations can trigger dislocation multiplication or diameter deviations, leading to decreased yield or even material failure. Based on the current specific material and growth technology, a reference temperature control strategy is obtained. By comparing the actual monitored temperature data within the vacuum pipeline, the reference temperature data curve, and the currently permissible fluctuation range, accurate pressure data is obtained to compensate for temperature changes. The greater the fluctuation and the more significant and rapid the difference, the greater the temperature deviation at the current monitoring moment.

[0056] In this embodiment of the invention, the method for obtaining the temperature offset index includes:

[0057] The difference between the current temperature data and the reference temperature data is taken as the current temperature fluctuation. The ratio between the temperature fluctuation and the preset allowable fluctuation is taken as the current temperature deviation index. It should be noted that the preset allowable fluctuation is the standard temperature fluctuation range. In this embodiment of the invention, it can be set to 5. The implementer can adjust it according to the implementation scenario. There is no restriction here. The temperature fluctuation is reflected by the temperature deviation under the current monitoring through the relationship between the temperature fluctuation and the acceptable fluctuation level.

[0058] In classical crystal growth theory, the growth rate may have an exponential relationship with temperature, following the Arrhenius equation, meaning the rate increases with increasing temperature until it decreases due to thermodynamic limitations after a certain critical temperature. When the crystal growth rate changes in conjunction with temperature data, it reflects the current state of the crystal conforming to the standard growth process. Therefore, it is necessary to appropriately reduce the temperature compensation at the current monitoring moment to obtain accurate pressure data within the vacuum pipeline.

[0059] However, considering the physical process of crystal growth, temperature changes may not immediately affect the growth rate, exhibiting a certain lag effect. Therefore, it is necessary to consider the impact of the time lag on the correlation between the two and find the correlation at the optimal lag time. At this optimal time, the correlation more accurately reflects the crystal growth at the current monitoring moment, thus obtaining accurate temperature compensation data. When the trend correlation between temperature and growth rate is high, it is considered that the current growth state is in a standard state, indicating that the temperature compensation requirement is low and the crystal growth is in a steady state. When the trend correlation between temperature and growth rate is too low, it may be due to thermal field deviation, contamination, or equipment failure, requiring enhanced compensation to correct the pressure data.

[0060] Firstly, to ensure analysis of delays and lags, a matching growth relationship is established by cross-checking temperature data and growth rate, and the impact is further analyzed through growth analysis. In this embodiment of the invention, the method for obtaining the matching group includes:

[0061] Curve fitting was performed on temperature data and growth rate over time to obtain temperature data curves and growth rate curves. The changes in these curves reflect the changes in the data over time. Please refer to [link / reference needed]. Figure 2 The diagram illustrates a temperature data curve and a growth rate curve provided in an embodiment of the present invention. The horizontal axis represents time series, the vertical axis represents data values, and the rising portion between the dashed lines represents the growth segment.

[0062] Further calculations are performed on the slopes of the temperature and growth rate curves at each moment. Periods with consecutive positive slopes are designated as growth segments. A positive slope indicates that the temperature or growth rate is in an upward phase, corresponding to the active period of crystal growth. Matching these upward segments helps identify how temperature changes affect the growth rate, especially the time-lag effect. Simultaneously, the length of the growth segment is greater than a preset minimum time period length to ensure the continuous and effective influence of the time period. In this embodiment, the preset minimum time period length can be set to 7, which can be adjusted by the implementer and is not limited herein.

[0063] It should be noted that curve fitting and slope calculation are techniques well known to those skilled in the art, such as least squares fitting, and will not be elaborated or limited here.

[0064] The growth rate of a crystal generally does not immediately reflect the growth state due to temperature changes. In other words, temperature changes have a lag time before fully affecting the crystal's growth rate. Therefore, when matching dynamically occurring growth periods, it is necessary to ensure that the growth segment in the growth rate curve follows the growth segment in the temperature data curve. For any growth segment of the temperature data curve, the growth segment in the growth rate curve that is closest to and follows the initial time of that growth segment is considered its matching segment. Each growth segment and its corresponding matching segment form a pair, which together constitute a matching segment group.

[0065] To further consider the delay under different matching conditions, in this embodiment of the invention, the method for obtaining the time delay includes: in each matching segment group, the time difference between the initial moments of the two growth segments is used as the initial delay deviation value, and the time difference between the final moments of the two growth segments is used as the final delay deviation value. Combining the different delay conditions at the start and end moments between the matching segments, the delay between the matching segment groups is comprehensively obtained, and the average of the initial delay deviation value and the final delay deviation value is used as the time delay of each matching segment group.

[0066] The higher the synchronization trend between temperature data and growth rate data, and the smaller the time delay of the corresponding matching segment group and the more stable the changes in all time delays, the smaller the delay effect of temperature changes in the vacuum pipe on the crystal growth rate. When the delay is larger and the delay may fluctuate significantly over time, that is, the more unstable the time delay, the more significant the delay effect of temperature changes in the vacuum pipe on the crystal growth rate is. This requires greater temperature compensation to offset the time of temperature changes and thus obtain more accurate pressure data.

[0067] Therefore, by combining the consistency between the temperature data and the growth rate trend, as well as the stability of the time delay, the influence degree of temperature delay is obtained. Preferably, in this embodiment of the invention, the method for obtaining the influence degree of temperature delay includes:

[0068] First, for any matching segment group, the temperature data curve and growth rate curve in the matching segment group are matched using the DTW algorithm to obtain matching pairs. Matching pairs may exist not only in one-to-one relationships, but also in one-to-many or many-to-many relationships. Therefore, the slope difference between the temperature data curve and the growth rate curve in each matching pair is calculated as the synchronization deviation degree of each matching pair. In this embodiment of the invention, if there is a multiple matching relationship in a matching pair, the slope difference between the temperature data curve and the growth rate curve at each time point is calculated, and the average of all slope differences is used as the synchronization deviation degree.

[0069] It should be noted that the method by which the DTW algorithm obtains matching pairs is a well-known technique familiar to those skilled in the art, and will not be elaborated upon here.

[0070] Within a comprehensive matching segment group, there are matching pairs. The sum of the synchronization deviations of all matching pairs is used as the accompanying deviation index for that matching segment group, reflecting the degree of synchronization deviation. Therefore, the average of the accompanying deviation indices of all matching segment groups yields the synchronization growth deviation index. The smaller the overall deviation, the more consistent the dynamic accompanying growth of temperature and growth rate, indicating a smaller impact of temperature data on the delay of crystal growth rate, which in turn has a smaller impact on the measured pressure data.

[0071] Furthermore, considering the stability of the delay, the product of the mean and standard deviation of the delay of all matched segments is used to obtain the delay instability index. The higher the overall delay and the larger the standard deviation, the more severe and unstable the delay is, and the greater the impact of the delay.

[0072] Therefore, the product of the synchronous growth deviation index and the delay instability index is ultimately used as the temperature delay impact degree, reflecting the extent to which the temperature can be compensated for due to the delay effect.

[0073] S3: Based on the changes in the deviation between the pressure data and the reference pressure data at each moment in the time series, and the changes in the corresponding time delay at each moment, combined with the influence of temperature delay, the current delay compensation index is obtained.

[0074] The time delay reflects the lag time by which temperature changes affect the growth rate. A longer lag time may mean that temperature changes take longer to affect the growth rate, potentially leading to unaccounted-for temperature delay effects in pressure measurements and thus larger errors. Therefore, if the pressure error increases proportionally with the increase in time delay, it indicates that the uncompensated delay does indeed affect the accuracy of the pressure measurement. Conversely, applying time delay compensation should reduce the pressure error, verifying the effectiveness of the compensation.

[0075] Therefore, considering the error in the pressure data and combining it with the influence of temperature delay, the final compensable situation is obtained. Preferably, in this embodiment of the invention, the method for obtaining the delay compensation index includes:

[0076] First, the difference between the pressure data at each moment and the reference pressure data is taken as the pressure deviation at each moment. The ratio of the pressure deviation to the reference pressure data is taken as the pressure error index at each moment, reflecting the possible degree of error in pressure monitoring under measurement.

[0077] Then, curve fitting was performed on the time delay and pressure error indices respectively to obtain the time delay data curve and the pressure error curve. Please refer to [link / reference needed]. Figure 3 The diagram illustrates a time delay data curve and a pressure error curve provided by an embodiment of the present invention. The horizontal axis represents the time sequence, and the vertical axis represents the data value. When the time delay is large, the pressure error is also large.

[0078] Therefore, the stronger the correlation between the time delay and the pressure error, the more effective the verification compensation. The correlation between the time delay data curve and the pressure error curve is calculated and normalized to obtain the pressure delay influence. In this embodiment of the invention, the Pearson correlation coefficient can be used to calculate the correlation. It should be noted that the Pearson correlation coefficient and normalization are well-known techniques to those skilled in the art. The normalization method can be linear normalization or standard normalization, etc. The specific normalization method is not limited here.

[0079] Finally, the product of the pressure delay effect and the temperature delay effect is used as the delay compensation index. The final delay compensation level is obtained through temperature delay analysis and pressure verification analysis.

[0080] S4: Combine the current delay compensation index and temperature offset index to adjust the current temperature data and obtain temperature compensation data; determine the current adjustment pressure data through the temperature compensation data.

[0081] By compensating for the time delay at the current monitoring moment, combined with the degree of temperature deviation, the current temperature data is compensated, thereby obtaining measurement data that more accurately reflects the true pressure data and avoiding errors caused by time delays during the crystal growth stage.

[0082] Preferably, in this embodiment of the invention, the method for obtaining temperature compensation data includes: multiplying the delay compensation index and the temperature offset index as the temperature adjustment degree; controlling the offset degree to ensure that the temperature does not exceed the reference temperature data at this time; compensating for the lag time within the compensation time window; and ensuring the match between the current temperature data and historical growth rate data. The greater the time delay, the greater the temperature compensation should be, and the temperature offset degree data can reflect the amount of missing temperature data relative to the standard temperature data at the current monitoring moment, thus ensuring the accuracy of the compensation data.

[0083] Finally, the sum of the current temperature data and the temperature adjustment value is used as the temperature compensation data. When the crystal is growing normally, the time delay compensation and temperature deviation will show small data values, that is, the compensation is weakened, and the real-time measured temperature data is trusted. Under abnormal conditions, the actual measured temperature data can be forcibly enhanced to increase compensation.

[0084] During crystal growth, pressure measurements within the vacuum pipeline are significantly affected by temperature fluctuations and time delay effects. Compensated temperature data obtained through dynamic compensation calculations can more accurately reflect the actual thermal field state. In this embodiment of the invention, the temperature compensation data is substituted into the ideal gas equation PV=nRT to generate corrected adjustment pressure data.

[0085] By adjusting the temperature hysteresis deviation in real time, pressure measurement errors are reduced, significantly improving data reliability. Ultimately, the updated adjusted pressure data can accurately characterize the vacuum environment state. In this embodiment of the invention, after completing dynamic temperature compensation and pressure correction, closed-loop optimization of the process can be achieved through multi-source data fusion and growth quality assessment. Specifically, firstly, the compensated temperature, corrected pressure, and growth rate data are aligned and normalized to eliminate dimensional differences. Then, the root causes such as temperature gradient deviation, abnormal pressure-rate relationship, or equipment execution errors are located, including thermal field shifts, contamination, or hardware failures. These are fed back to the control system to achieve automatic iterative adjustment of parameters such as heating power and melt cleaning. Simultaneously, the entire process data is archived to a time-series database, and models such as LSTM are used to predict the temperature-rate hysteresis effect, dynamically updating the compensation parameters, delay compensation index, and temperature shift index. This ultimately forms a "monitoring-compensation-evaluation-optimization" closed loop, significantly improving crystal yield and providing data-driven decision support for the large-scale production of semiconductor-grade single crystals.

[0086] In summary, this invention quantifies the temperature offset effect of the vacuum pipeline during crystal growth, real-time assesses thermal field anomalies in the vacuum pipeline, and provides precise input for compensation. It analyzes the dynamic growth of temperature data and growth rate, identifying the time delay between temperature data and growth rate through matching segment groups, thus clarifying the lag effect of temperature changes on the growth rate. By analyzing the relationship between the temperature data of the vacuum pipeline and the time delay of crystal growth rate during crystal growth, as well as pressure deviation changes, it analyzes the dynamic compensation for temperature lag, and provides the compensability level based on the impact of the delay relationship on pressure measurement. Finally, after temperature data compensation based on compensation and offset indices, the current pressure measurement data is updated and adjusted, making the temperature-based adjustments more accurate. This invention analyzes the dynamic interaction between temperature and crystal growth, determines time delay compensation through the degree of accompanying time delay, combines temperature offset compensation with pressure data adjustment, and enables the measured pressure data to more accurately reflect the pressure conditions during crystal growth, improving the accuracy of pressure measurement.

[0087] The present invention also provides a pressure measuring device for a vacuum pipeline of a single crystal furnace, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of a pressure measuring method for a vacuum pipeline of a single crystal furnace as described in any of the above claims.

[0088] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0089] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

Claims

1. A method for measuring pressure in a vacuum pipeline of a single crystal furnace, characterized in that, The method includes: During the crystal growth stage, temperature and pressure data are collected at each moment, and the crystal growth rate at each moment is obtained. Based on the fluctuation deviation between the current temperature data and the reference temperature data, the temperature offset index for the current moment is obtained; in terms of time series, matching analysis is performed based on the correlation between the growth trend of temperature data and growth rate to obtain matching segment groups; the time delay of each matching segment group is obtained by the time deviation between temperature data and growth rate in the matching segment group; and the current temperature delay impact is obtained by combining the consistency of the growth trend between temperature data and growth rate in all matching segment groups and the instability of the time delay. Based on the changes in the deviation between the pressure data and the reference pressure data at each moment in the time series, and the changes in the corresponding time delay at each moment, combined with the influence of temperature delay, the current delay compensation index is obtained. By combining the current delay compensation index and temperature offset index, the current temperature data is adjusted to obtain temperature compensation data; the current adjustment pressure data is then determined using the temperature compensation data. The method for obtaining matching groups includes: performing curve fitting on temperature data and growth rate in time series to obtain temperature data curves and growth rate curves; calculating the slope of temperature data curves and growth rate curves at each moment, and taking the time period with a continuous positive slope as a growth segment; the length of the growth segment is greater than the preset minimum time period length; for any growth segment of the temperature data curve, taking the growth segment of the growth rate curve that is closest to the initial moment of the growth segment as the matching segment of the growth segment; and taking the tuple formed by each growth segment and its corresponding matching segment as a matching segment group. The method for obtaining the impact of temperature delay includes: for any matching segment group, matching the temperature data curve and the growth rate curve in the matching segment group using the DTW algorithm to obtain matching pairs; calculating the slope difference between the temperature data curve and the growth rate curve in each matching pair as the synchronization deviation degree of each matching pair; summing the synchronization deviation degrees of all matching pairs as the accompanying deviation index of the matching segment group; averaging the accompanying deviation indices of all matching segment groups to obtain the synchronization growth deviation index; multiplying the mean of the time delay amount and the standard deviation of the time delay amount of all matching segments to obtain the delay instability index; and multiplying the synchronization growth deviation index and the delay instability index as the impact of temperature delay. Methods for obtaining the adjustment pressure include: substituting temperature compensation data into the ideal gas equation to obtain the adjustment pressure data; The method for obtaining the time delay includes: in each matching segment group, the time difference between the initial moments of the two growth segments is used as the initial delay deviation value; the time difference between the final moments of the two growth segments is used as the final delay deviation value; and the average of the initial delay deviation value and the final delay deviation value is used as the time delay of each matching segment group. The methods for obtaining temperature compensation data include: multiplying the delay compensation index and the temperature offset index as the temperature adjustment degree; and using the sum of the current temperature data and the temperature adjustment degree as the temperature compensation data. The growth rate is obtained by: obtaining the crystal mass increase, crystal density, and growth interface area at each time step; taking the ratio of the crystal mass increase to the growth time at each time step as the mass growth rate; performing a negative correlation mapping between the crystal density and the growth interface area as the growth unit influence degree; and taking the product of the mass growth rate and the growth unit influence degree as the growth rate at each time step.

2. The method for measuring pressure in a vacuum pipeline of a single crystal furnace according to claim 1, characterized in that, Methods for obtaining temperature offset indices include: The difference between the current temperature data and the reference temperature data is used as the current temperature fluctuation; the ratio between the temperature fluctuation and the preset allowable fluctuation is used as the current temperature deviation index.

3. The method for measuring pressure in a vacuum pipeline of a single crystal furnace according to claim 1, characterized in that, Methods for obtaining delay compensation metrics include: The difference between the pressure data at each moment and the reference pressure data is used as the pressure deviation at each moment; the ratio of the pressure deviation to the reference pressure data is used as the pressure error index at each moment. Curve fitting was performed on the time delay and pressure error indicators respectively to obtain the time delay data curve and the pressure error curve. The correlation between the time delay data curve and the pressure error curve is calculated and normalized to obtain the pressure delay influence degree; the product of the pressure delay influence degree and the temperature delay influence degree is used as the delay compensation index.

4. A pressure measuring device for a vacuum pipeline of a single crystal furnace, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of a single crystal furnace vacuum pipeline pressure measurement method as described in any one of claims 1 to 3.

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