Method and device for measuring pressure of vacuum pipeline of single crystal furnace

Abstract

The invention relates to the technical field of pressure detection, in particular to a single crystal furnace vacuum pipeline pressure measuring method and device. The method comprises the following steps: quantifying temperature deviation of a vacuum pipeline in a crystal growth process; carrying out matching analysis on the temperature data and the growth trend of the growth rate, and carrying out time delay identification on the temperature data and the growth rate through a matching section group; dynamic compensation of temperature lag is analyzed according to the relation between temperature data in the crystal growth process and the time delay change of the growth rate and the deviation change of pressure, and a delay compensation index is determined; and performing temperature data compensation according to the delay compensation index and the temperature offset to obtain current adjustment pressure measurement data. The dynamic accompanying condition of the temperature and the crystal growth is analyzed, the time delay compensation is determined through the accompanying time delay degree, the temperature data is compensated in combination with the temperature deviation, and the pressure is adjusted, so that the measured pressure data can more truly reflect the pressure condition in the crystal growth process, and the pressure measurement precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure detection, and particularly relates to a method and device for measuring the pressure of a vacuum pipeline of a single crystal furnace. Background Art

[0002] A single crystal furnace is a device that melts polycrystalline materials such as polysilicon with a graphite heater in an inert gas (mainly nitrogen and helium) environment and grows dislocation-free single crystals by the Czochralski method. In the modern semiconductor and photovoltaic industries, as a key device for producing high-quality single crystals, the vacuum environment during the operation of a single crystal furnace plays a decisive role in the quality of crystal growth. As an important channel for maintaining the internal vacuum state of a single crystal furnace, it is crucial to accurately measure the pressure of its vacuum pipeline. In the production of semiconductor-grade single crystal silicon, extremely small pressure fluctuations may cause crystal defects and affect the performance of chips. Therefore, a method capable of real-time and accurate measurement of the pressure of the vacuum pipeline is required to timely adjust the parameters of the vacuum system and ensure the stability of the crystal growth environment.

[0003] In the prior art, when directly measuring the pressure data inside the vacuum pipeline, there are error situations caused by changes in the ambient temperature inside the vacuum pipeline. Temperature changes will affect the thermal motion of gas, thereby changing the pressure characteristics of the gas and causing deviations in the measurement results. Considering the physical process of crystal growth, temperature changes may not respond in real time to the crystal growth rate, there is a certain lag effect, and there will also be deviations between temperature changes and the crystal growth process. This leads to adjustment deviations in the process of directly adjusting the measurement of the vacuum pipeline pressure by temperature, causing the true pipeline pressure data to be submerged, and thus affecting the monitoring of the crystal growth process in the single crystal furnace. Summary of the Invention

[0004] In order to solve the technical problem that the true pipeline pressure data is submerged due to the adjustment deviation generated in the process of directly adjusting the measurement of the vacuum pipeline pressure by temperature in the prior art, the purpose of the present invention is to provide a method and device for measuring the pressure of a vacuum pipeline of a single crystal furnace, and the specific technical solutions adopted are as follows: The present invention provides a method for measuring the pressure of a vacuum pipeline of a single crystal furnace, and the method includes: During the crystal growth stage, collect the temperature data and pressure data at each moment, and obtain the growth rate of the crystal at each moment; Obtain the temperature offset index according to the fluctuation deviation between the temperature data at the current moment and the reference temperature data; in terms of time series, perform matching analysis according to the correlation between the growth trend of the temperature data and the growth rate to obtain the matching segment group; obtain the time delay amount of each matching segment group through the time deviation between the temperature data and the growth rate in the matching segment group; combine the consistency of the growth trend between the temperature data and the growth rate in all matching segment groups and the instability degree of the time delay amount to obtain the current temperature delay influence degree; Obtain the current delay compensation index based on the change in the deviation between the pressure data and the reference pressure data at each moment in the time series, the change in the time delay amount corresponding to each moment, and in combination with the temperature delay influence degree; Combine the current delay compensation index and the temperature offset index to adjust the current temperature data to obtain the temperature compensation data; determine the current adjusted pressure data through the temperature compensation data.

[0005] Furthermore, the method for obtaining the temperature offset index includes: Take the difference between the temperature data at the current moment and the reference temperature data as the current temperature fluctuation degree; take the ratio between the temperature fluctuation degree and the preset allowable fluctuation degree as the temperature offset index at the current moment.

[0006] Furthermore, the method for obtaining the matching group includes: Perform curve fitting on the temperature data and the growth rate respectively in the time series to obtain the temperature data curve and the growth rate curve; calculate the slope of the temperature data curve and the growth rate curve at each moment, and take the period with a continuously positive slope as the growth segment; the length of the growth segment is greater than the preset minimum period length; For any growth segment of the temperature data curve, take the growth segment in the growth rate curve that is after the initial moment of this growth segment and closest to the initial moment of this growth segment as the matching segment of this growth segment; take the binary group composed of each growth segment and its corresponding matching segment as a matching segment group.

[0007] Furthermore, the method for obtaining the time delay amount includes: In each matching segment group, take the time difference between the initial moments of the two growth segments as the initial delay deviation value; take the time difference between the final moments of the two growth segments as the final delay deviation value; Take the average value of the initial delay deviation value and the final delay deviation value as the time delay amount of each matching segment group.

[0008] Furthermore, the method for obtaining the temperature delay influence degree includes: For any matching segment group, the temperature data curve and the growth rate curve in the matching segment group are matched through the DTW algorithm to obtain matching pairs; the slope differences between the temperature data curve and the growth rate curve in each matching pair are calculated respectively as the synchronization deviation degrees of each matching pair; the sum value of the synchronization deviation degrees of all matching pairs is used as the accompanying deviation index of the matching segment group; the mean value of the accompanying deviation indexes of all matching segment groups is obtained to get the synchronization growth deviation index; The product of the mean value of the time delay amounts of all matching segments and the standard deviation of the time delay amounts is obtained to get the delay instability index; The product of the synchronization growth deviation index and the delay instability index is used as the temperature delay influence degree.

[0009] Furthermore, the method for obtaining the delay compensation index includes: The difference between the pressure data at each moment and the reference pressure data is used as the pressure deviation degree at each moment; the ratio of the pressure deviation degree to the reference pressure data is used as the pressure error index at each moment; The time delay amount and the pressure error index are respectively curve-fitted in time sequence to obtain the time delay amount data curve and the pressure error curve; The correlation degree between the time delay amount 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.

[0010] Furthermore, the method for obtaining the temperature compensation data includes: The product of the delay compensation index and the temperature offset index is used as the temperature adjustment degree; the sum value of the temperature data at the current moment and the temperature adjustment degree is used as the temperature compensation data.

[0011] Furthermore, the method for obtaining the adjusted pressure includes: The temperature compensation data is substituted into the ideal gas equation to obtain the adjusted pressure data.

[0012] Furthermore, the method for obtaining the growth rate includes: Obtain the crystal mass increase amount, crystal density and growth interface area at each moment; The ratio of the crystal mass increase amount at each moment to the growth duration is used as the mass growth rate; the product of the crystal density and the growth interface is negatively correlated and mapped as the growth unit influence degree; The product of the mass growth rate and the growth unit influence degree is used as the growth rate at each moment.

[0013] The present invention also provides a pressure measuring device for a vacuum pipeline of a single crystal furnace, which includes a memory, a processor, and a computer program stored in the memory and operable on the processor. When the processor executes the computer program, the steps of a pressure measuring method for a vacuum pipeline of a single crystal furnace as described in any one of the above are implemented.

[0014] The present invention has the following beneficial effects: By quantifying the temperature offset effect of the vacuum pipeline during the crystal growth process, the present invention can evaluate the thermal field abnormality of the vacuum pipeline in real time and provide a precise input degree for compensation. Analyze the dynamic growth accompaniment of temperature data and growth rate, identify the time delay amount between temperature data and growth rate through matching segment groups, and clarify the lag effect of temperature change on growth rate. Based on the relationship between the temperature data of the vacuum pipeline during the crystal growth process, the change of the time delay amount of the crystal growth rate, and the deviation change of pressure, analyze the dynamic compensation of temperature lag, and provide a compensable degree according to the influence of the delay relationship on pressure measurement. Finally, after compensating the temperature data according to the compensation index and offset index, update and adjust the current pressure measurement data to make the temperature adjustment more accurate. The present invention analyzes the dynamic accompaniment of temperature and crystal growth, determines the delay compensation through the accompanying delay degree, combines the temperature offset to compensate the temperature data and adjust the pressure data, so that the measured pressure data can more truly reflect the pressure condition during the crystal growth process and improve the accuracy of pressure measurement. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 It is a flowchart of a pressure measuring method for a vacuum pipeline of a single crystal furnace provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of a temperature data curve and a growth rate curve provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a time delay amount data curve and a pressure error curve provided by an embodiment of the present invention. Detailed Embodiments

[0017] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following specifically describes, in conjunction with the accompanying drawings and preferred embodiments, a method and device for measuring the pressure of a vacuum pipeline of a single crystal furnace according to the present invention, including its specific implementation manner, structure, features, and effects. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0019] The following specifically describes the specific solution of a method and device for measuring the pressure of a vacuum pipeline of a single crystal furnace provided by the present invention in conjunction with the accompanying drawings.

[0020] Please refer to Figure 1 , which shows a flowchart of a method for measuring the pressure of a vacuum pipeline of a single crystal furnace provided by an embodiment of the present invention. The method includes the following steps: S1: During the crystal growth stage, collect temperature data and pressure data at each moment, and obtain the growth rate of the crystal at each moment.

[0021] The pressure measurement of the vacuum pipeline is crucial for the quality of crystal growth, and there is a close correlation between the pressure measurement and the real-time change of temperature. Therefore, during the crystal growth process in an ideal vacuum pipeline, corresponding reference temperature data and reference pressure data are obtained as ideal data for analyzing the actual detection.

[0022] Temperature probes are arranged at key positions in the pipeline, such as the sensor installation point, the air extraction port, the process area, etc. Since the temperature varies at different positions in the vacuum pipeline, weight values are assigned to the temperatures at different positions, and the weighted average temperature is calculated as the temperature data at each moment during monitoring. Similarly, the pressure data at each moment is obtained.

[0023] It should be noted that through multi-sensor layout, such as real-time monitoring of the temperature at key positions by thermocouples and infrared thermometers. In the specific operation of the embodiment of the present invention, the thermocouple needs to be inserted into the melt to a depth of ≥30 mm, the emissivity of the infrared thermometer is set to 0.9, and it is calibrated with a blackbody radiation source every week to ensure that the temperature data error < ±0.3 °C, providing reliable temperature input for subsequent pressure correction and avoiding systematic errors caused by inaccurate temperature measurement.

[0024] During the crystal growth process, temperature directly affects the viscosity of the melt, the diffusion coefficient, and the thermodynamic conditions of the solid-liquid interface. Different temperature gradients will result in different growth rates and crystal qualities. The growth rate generally refers to the length or volume that the crystal grows along a specific direction, such as the axial or radial direction, per unit time. For single crystal growth, such as growing single crystal silicon using the Czochralski method, the growth rate can be determined by measuring the pulling speed and diameter change of the crystal.

[0025] Therefore, to analyze the relationship between temperature and growth rate, it is necessary to understand how temperature affects the kinetic process of crystal growth, such as the attachment and diffusion of atoms or molecules at the solid-liquid interface. In the embodiments of the present invention, during the single crystal growth process, the crystal mass increase, crystal density, and growth interface area at each moment are obtained, and the growth rate is quantified through the data of each dimension index. The ratio of the crystal mass increase at each moment to the growth duration is used as the mass growth rate to reflect the mass change situation. The product of the crystal density and the growth interface is negatively correlated and mapped as the influence degree of the growth unit to reflect the influence degree of the attachment surface and density.

[0026] It should be noted that negative correlation mapping is a well-known technical means in the art, such as in the form of inverse proportion or negative exponential power, etc., which will not be elaborated and limited herein.

[0027] Finally, the product of the mass growth rate and the influence degree of the growth unit is used as the growth rate at each moment. As an example, the expression of the growth rate is: , where, represents the growth rate, represents the crystal mass increase, represents the growth duration corresponding to the crystal mass increase, is the crystal density, is the growth interface area, represents the mass growth rate, represents the influence degree of the growth unit.

[0028] S2: Obtain the temperature offset index at the current moment according to the fluctuation deviation between the current moment temperature data and the reference temperature data; in terms of time sequence, perform matching analysis according to the correlation situation of the growth trends between the temperature data and the growth rate to obtain the matching segment group; obtain the time delay amount of each matching segment group through the time deviation between the temperature data and the growth rate in the matching segment group; combine the consistent situation of the growth trends between the temperature data and the growth rate in all matching segment groups and the instability degree of the time delay amount to obtain the current temperature delay influence degree.

[0029] According to the ideal gas law PV = nRT, when the volume V and the amount of substance n of an object remain unchanged, a change in temperature T will cause a linear change in pressure P. In the vacuum pipeline of a single crystal furnace, the temperature fluctuation can be very large, ranging from room temperature to several hundred degrees Celsius. At this time, when directly obtaining pressure data, there will be deviations due to the influence of temperature. Moreover, during different growth stages, temperature changes will affect gas expansion and pressure fluctuations. Therefore, it is necessary to monitor temperature data in real time to ensure the accuracy of pressure control.

[0030] Since crystal growth is extremely sensitive to temperature gradients, tiny temperature fluctuations can trigger dislocation multiplication or diameter deviation, resulting in a decrease in the yield rate or even scrapping of the material. According to the current specific material and growth technology, obtain its reference temperature control strategy. By comparing the actually monitored temperature data in the vacuum pipeline, the reference temperature data curve, and the currently allowed fluctuation range, temperature compensation is then carried out to obtain accurate pressure data. The greater the fluctuation and the more significant and rapid the process of generating differences, the greater the degree of temperature offset at the current monitoring moment.

[0031] In the embodiment of the present invention, the method for obtaining the temperature offset index includes: Taking the difference between the temperature data at the current moment and the reference temperature data as the current temperature fluctuation degree, and taking the ratio between the temperature fluctuation degree and the preset allowable fluctuation degree as the temperature offset index at the current moment. It should be noted that the preset allowable fluctuation degree is the standard temperature fluctuation range, which can be set to 5 in the embodiment of the present invention, and the implementer can adjust it according to the implementation scenario, and no limitation is made here. The temperature offset degree under the current monitoring is reflected by the temperature fluctuation relative to the acceptable fluctuation degree.

[0032] In the classical crystal growth theory, the growth rate may have an exponential relationship with temperature and follow the Arrhenius equation, that is, the rate increases with the increase in temperature until it may decrease due to thermodynamic limitations after a certain critical temperature. When the growth rate of the crystal changes along with the temperature data, it can reflect the state of the current crystal conforming to the standard growth process. Therefore, it is necessary to correspondingly weaken the temperature compensation at the current monitoring moment to obtain accurate pressure data in the vacuum pipeline.

[0033] However, considering the physical process of crystal growth, temperature changes may not immediately affect the growth rate, and there is a certain lag effect. Therefore, it is necessary to consider the influence of the time lag on the correlation between the two, and find the correlation at the optimal lag time. At this time, the correlation can more accurately reflect the crystal growth at the current monitoring moment, and then obtain accurate temperature compensation data. When the trend correlation between temperature and growth rate is higher, it is considered that the current is in the standard growth state, indicating a lower temperature compensation requirement and the crystal growth is in a steady state. When the trend correlation between temperature and growth rate is too low, it may be caused by thermal field deviation, contamination or equipment failure, and compensation needs to be enhanced to correct the pressure data.

[0034] First, in order to ensure the analysis of the delay situation, a matching growth relationship is established by cross-checking the temperature data and the growth rate, and the influence is further analyzed through the growth situation. In the embodiment of the present invention, the method for obtaining the matching group includes: Perform curve fitting on the temperature data and the growth rate respectively in time series to obtain the temperature data curve and the growth rate curve, and reflect the change of the data in time series through the curve change. Please refer to Figure 2 , which shows a schematic diagram of a temperature data curve and a growth rate curve provided by an embodiment of the present invention. The abscissa is the time series, the ordinate is the data value, and the rising part between the dotted lines represents the growth segment.

[0035] Furthermore, calculate the slope of the temperature data curve and the growth rate curve at each moment, and use the period with a continuous positive slope as the growth segment. A positive slope represents that the temperature or the growth rate is in the rising stage, corresponding to the active period of crystal growth. Matching these rising segments subsequently can help identify how temperature changes affect the growth rate, especially the lag effect in time. At the same time, the length of the growth segment is greater than the preset minimum period length to ensure that the period is continuously effective and has an influence effect. In the embodiment of the present invention, the preset minimum period length can be set to 7, and the implementer can adjust it by himself / herself, and no limitation is made here.

[0036] It should be noted that curve fitting and slope calculation are both technical means well-known to those skilled in the art, such as fitting by the least squares method, etc., and no further elaboration and limitation are made here.

[0037] Generally, the growth rate of the crystal will not immediately reflect its growth state due to the influence of temperature, that is, after the temperature data changes pass through the lag time, they can fully act on the growth rate of the crystal. Therefore, when matching the dynamically accompanied growth periods, it is necessary to ensure that the growth segment in the growth rate curve is located after 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 after the initial moment of this growth segment and closest to the initial moment of this growth segment is used as the matching segment of this growth segment, and the binary group composed of each growth segment and its corresponding matching segment is used as a matching segment group.

[0038] Further considering the delay situation under different matches, in the embodiments of the present invention, the method for obtaining the time delay amount includes: in each match segment group, taking the time difference between the initial moments of two growth segments as the initial delay deviation value, and taking the time difference between the final moments of two growth segments as the final delay deviation value. Combining the different time delay situations at the start and end moments between match segments, comprehensively obtaining the delay situation between match segment groups, and taking the average value of the initial delay deviation value and the final delay deviation value as the time delay amount of each match segment group.

[0039] When the synchronous trend of the growth of temperature data and growth rate data is higher, and at this time the time delay amount of the corresponding match segment group is smaller and all time delay amounts change more stably, it can be shown that the delay effect of the change in temperature in the vacuum pipeline on the growth rate of the crystal is smaller. When the delay amount is larger, and the delay amount may fluctuate greatly with time, that is, the time delay amount is more unstable, it can reflect a more significant delay effect of the change in temperature data in the vacuum pipeline on the growth rate of the crystal, and thus a larger temperature compensation is required to offset the time of temperature change, so as to obtain more accurate pressure data.

[0040] Therefore, combining the consistent situation of the growth trends of temperature data and growth rate, and the stability of the time delay amount, the temperature delay influence degree is obtained. Preferably, in the embodiments of the present invention, the method for obtaining the temperature delay influence degree includes: First, for any match segment group, the temperature data curve and the growth rate curve in this match segment group are matched by the DTW algorithm to obtain match pairs. The match pairs not only have a one-to-one relationship, but may also have a one-to-many or many-to-many relationship. Therefore, the slope difference between the temperature data curve and the growth rate curve in each match pair is calculated respectively as the synchronous deviation degree of each match pair. In the embodiments of the present invention, in the match pair, if there is a multi-match relationship, the slope difference between the temperature data curve and the growth rate curve at each match moment is calculated, and the average value of all slope differences is used as the synchronous deviation degree.

[0041] It should be noted that the method of obtaining match pairs by the DTW algorithm is a well-known technical means for those skilled in the art and will not be elaborated here.

[0042] Among all the matching pairs in the comprehensive matching segment group, the sum of the synchronization deviation degrees of all the matching pairs is used as the accompanying deviation index of this matching segment group, which reflects the deviation degree of synchronization. Therefore, the mean value of the accompanying deviation indexes of all the matching segment groups is obtained as the synchronization growth deviation index. The smaller the overall deviation degree is, the more consistent the dynamic accompanying growth degree between the temperature and the growth rate is, which can reflect that the delay effect of the temperature data on the crystal growth rate is smaller at this time, that is, the influence on the measured pressure data is smaller.

[0043] Furthermore, considering the time-delay stability situation, the product of the mean value of the time delay amounts of all the matching segments and the standard deviation of the time delay amounts is obtained as the time-delay instability index. The higher the overall time delay amount and the larger the standard deviation are, the more serious and unstable the time-delay degree is, and the higher the delay effect is.

[0044] Therefore, finally, the product of the synchronization growth deviation index and the time-delay instability index is used as the temperature delay influence degree, which reflects the degree to which the temperature can be compensated due to the time-delay effect.

[0045] S3: According to the change of the deviation between the pressure data and the reference pressure data at each moment in time sequence, and the change of the corresponding time delay amount at each moment, combined with the temperature delay influence degree, the current delay compensation index is obtained.

[0046] The time delay amount reflects the lag time for the temperature change to affect the growth rate. If the lag time is long, it may mean that it takes longer for the temperature change to affect the growth rate, which may lead to the delay effect of the temperature change not being considered during pressure measurement, thus resulting in a larger error. Therefore, when the time delay amount increases, if the pressure error also increases synchronously, it indicates that the uncompensated delay does affect the accuracy of pressure measurement. On the contrary, when time-delay compensation is applied, the pressure error should decrease, verifying the effectiveness of the compensation.

[0047] Therefore, considering the error situation of the pressure data and combining with the temperature delay influence degree, the final compensable situation is obtained. Preferably, in the embodiment of the present invention, the method for obtaining the delay compensation index includes: First, the difference between the pressure data and the reference pressure data at each moment is used as the pressure deviation degree at each moment, and the ratio of the pressure deviation degree to the reference pressure data is used as the pressure error index at each moment, which reflects the possible error degree of pressure monitoring under measurement.

[0048] Furthermore, curve fitting is respectively performed on the time delay amount and the pressure error index in time sequence to obtain the time delay amount data curve and the pressure error curve. Please refer to Figure 3 , which shows a schematic diagram of a time delay amount data curve and a pressure error curve provided by an embodiment of the present invention. The abscissa is the time sequence, and the ordinate is the data value. When the time delay amount has a large value, the pressure error at this time is also large.

[0049] Therefore, when the correlation between the time delay amount and the pressure error is stronger, the verification compensation is more effective. Calculate the correlation between the time delay amount data curve and the pressure error curve and perform normalization processing to obtain the pressure delay influence degree. In the embodiments of the present invention, the Pearson correlation coefficient can be used to calculate the correlation. It should be noted that the Pearson correlation coefficient and normalization are technical means well-known to those skilled in the art. The choice of normalization can be linear normalization or standard normalization, etc. The specific normalization method is not limited herein.

[0050] Finally, take the product of the pressure delay influence degree and the temperature delay influence degree as the delay compensation index, and obtain the final delay compensation degree through the delay analysis of temperature and the verification analysis of pressure.

[0051] S4: Combine the current delay compensation index and the temperature offset index to adjust the current temperature data to obtain temperature compensation data; determine the current adjusted pressure data through the temperature compensation data.

[0052] Compensate the current temperature data through the time delay compensation degree at the current monitoring moment, combined with the temperature offset degree, so as to obtain measurement data that more accurately reflects the real pressure data and avoid errors caused by time delay during the crystal growth stage.

[0053] Preferably, in the embodiments of the present invention, the method for obtaining temperature compensation data includes: taking the product of the delay compensation index and the temperature offset index as the temperature adjustment degree, and through offset degree control, ensure that it does not exceed the reference temperature data at this time, make up the compensation time window for the lag time, and ensure the matching of the current temperature data and the historical growth rate data. When the time delay degree is greater, the compensation for temperature should be greater, and the temperature offset degree data can reflect the missing amount of the temperature at the current monitoring moment relative to the standard temperature data. Therefore, the accuracy of the compensation data can be guaranteed.

[0054] Finally, take the sum value of the temperature data at the current moment and the temperature adjustment degree as the temperature compensation data. When the crystal is growing normally, the time delay compensation degree and the temperature offset degree will show smaller data values, that is, weaken the compensation and trust the real-time measured temperature data. When in an abnormal state, the compensation for the actually measured temperature data can be forced to be enhanced.

[0055] During the crystal growth process, the pressure measurement in the vacuum pipeline is significantly affected by temperature fluctuations and time delay effects. The compensated temperature data obtained through dynamic compensation calculation can more truly reflect the actual thermal field state. In the embodiments of the present invention, substitute the temperature compensation data into the ideal gas equation PV = nRT to generate the corrected adjusted pressure data.

[0056] By adjusting the temperature hysteresis deviation in real time, the pressure measurement error is reduced, and the data reliability is significantly improved. Finally, the updated adjusted pressure data can accurately characterize the vacuum environment state. In the embodiment of the present invention, after completing the dynamic temperature compensation and pressure correction, the process closed-loop optimization can be realized through multi-source data fusion and growth quality evaluation. Specifically, first, align the compensated temperature, corrected pressure, and growth rate data, and perform normalization processing to eliminate the dimension difference. Combine the temperature gradient deviation, abnormal pressure-rate relationship, or equipment execution error to locate the root causes such as thermal field offset, contamination, or hardware failure, and feedback to the control system to realize the automatic iterative adjustment of parameters such as heating power and melt cleaning. At the same time, archive the full-process data into the time-series database, and use models such as LSTM to predict the hysteresis effect of temperature-rate, dynamically update the compensation parameter delay compensation index and temperature offset index, and finally form a "monitoring-compensation-evaluation-optimization" closed loop, significantly improving the crystal yield and providing data-driven decision support for the large-scale production of semiconductor-grade single crystals.

[0057] In summary, the present invention quantifies the temperature offset effect of the vacuum pipeline during the crystal growth process, and evaluates the thermal field anomaly of the vacuum pipeline in real time, providing accurate input for compensation. Analyze the dynamic growth and matching of temperature data and growth rate, identify the time delay between temperature data and growth rate through the matching segment group, and clarify the hysteresis effect of temperature change on growth rate. Based on the relationship between the time delay change of the temperature data and the crystal growth rate and the deviation change of pressure during the crystal growth process, analyze the dynamic compensation of temperature hysteresis, and provide the compensable degree according to the influence of the time delay relationship on pressure measurement. Finally, after compensating the temperature data according to the compensation index and offset index, update and adjust the current pressure measurement data to make the temperature adjustment more accurate. The present invention analyzes the dynamic accompanying situation between temperature and crystal growth, determines the time delay compensation through the accompanying time delay degree, combines the temperature offset to compensate the temperature data and adjust the pressure data, so that the measured pressure data can more truly reflect the pressure condition during the crystal growth process and improve the accuracy of pressure measurement.

[0058] The present invention also provides a pressure measurement device for the vacuum pipeline of a single crystal furnace, including 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 realizes the steps of a pressure measurement method for the vacuum pipeline of a single crystal furnace as described in any one of the above.

[0059] It should be noted that the above sequence of embodiments of the present invention is only for description and does not represent the superiority or inferiority of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0060] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the differences between each embodiment and other embodiments are emphasized.

Claims

1. A method for measuring the pressure of a vacuum pipeline of a single crystal furnace, characterized in that, The method includes: In the crystal growth stage, collecting temperature data and pressure data at each moment, and obtaining the growth rate of the crystal at each moment; According to the fluctuation deviation between the temperature data at the current moment and the reference temperature data, obtaining the temperature offset index at the current moment; in terms of time sequence, performing matching analysis according to the correlation of the growth trends between the temperature data and the growth rate to obtain a matching segment group; through the time deviation between the temperature data and the growth rate in the matching segment group, obtaining the time delay amount of each matching segment group; combining the consistent growth trends between the temperature data and the growth rate in all matching segment groups and the instability degree of the time delay amount, obtaining the current temperature delay influence degree; Based on the change of the deviation between the pressure data at each moment in the time sequence and the reference pressure data and the change of the time delay amount corresponding to each moment, and combining the temperature delay influence degree, obtaining the current delay compensation index; Combining the current delay compensation index and the temperature offset index, adjusting the current temperature data to obtain temperature compensation data; determining the current adjusted pressure data through the temperature compensation data.

2. The method for measuring the pressure of the vacuum pipeline of a single crystal furnace according to claim 1, wherein, The method for obtaining the temperature offset index includes: Taking the difference between the temperature data at the current moment and the reference temperature data as the current temperature fluctuation degree; taking the ratio between the temperature fluctuation degree and the preset allowable fluctuation degree as the temperature offset index at the current moment.

3. The method for measuring the pressure of the vacuum pipeline of a single crystal furnace according to claim 1, wherein, The method for obtaining the matching group includes: Performing curve fitting on the temperature data and the growth rate respectively in the time sequence to obtain a temperature data curve and a growth rate curve; calculating the slope of the temperature data curve and the growth rate curve at each moment, and taking the period with a continuous positive slope as a growth segment; the length of the growth segment is greater than the preset minimum period length; For any growth segment of the temperature data curve, taking the growth segment in the growth rate curve that is after the initial moment of the growth segment and closest to the initial moment of the growth segment as the matching segment of the growth segment; taking the binary group composed of each growth segment and its corresponding matching segment as a matching segment group.

4. The method for measuring the pressure of a vacuum pipeline of a single crystal furnace according to claim 3, wherein, The method for obtaining the time delay amount includes: In each matching segment group, taking the time difference between the initial moments of the two growth segments as the initial delay deviation value; taking the time difference between the final moments of the two growth segments as the final delay deviation value; Taking the mean value of the initial delay deviation value and the final delay deviation value as the time delay amount of each matching segment group.

5. The method for measuring the pressure of the vacuum pipeline of a single crystal furnace according to claim 3, wherein The method for obtaining the temperature delay influence degree includes: For any matching segment group, performing matching on the temperature data curve and the growth rate curve in the matching segment group through 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 respectively as the synchronization deviation degree of each matching pair; taking the sum value of the synchronization deviation degrees of all matching pairs as the accompanying deviation index of the matching segment group; taking the mean value of the accompanying deviation indexes of all matching segment groups to obtain the synchronization growth deviation index; Obtaining the delay instability index by multiplying the mean value of the time delay amounts of all matching segments and the standard deviation of the time delay amounts; Taking the product of the synchronization growth deviation index and the delay instability index as the temperature delay influence degree.

6. The method for measuring the pressure of the vacuum pipeline of a single crystal furnace according to claim 1, wherein The method for obtaining the delay compensation index includes: Taking the difference between the pressure data at each moment and the reference pressure data as the pressure deviation degree at each moment; taking the ratio of the pressure deviation degree to the reference pressure data as the pressure error index at each moment; Performing curve fitting on the time delay amount and the pressure error index respectively in time series to obtain the time delay amount data curve and the pressure error curve; Calculating the correlation degree of the time delay amount data curve and the pressure error curve and performing normalization processing to obtain the pressure delay influence degree; taking the product of the pressure delay influence degree and the temperature delay influence degree as the delay compensation index.

7. The method for measuring the pressure of a vacuum pipeline of a single crystal furnace according to claim 1, wherein The method for obtaining the temperature compensation data includes: Taking the product of the delay compensation index and the temperature offset index as the temperature adjustment degree; taking the sum value of the temperature data at the current moment and the temperature adjustment degree as the temperature compensation data.

8. A method for measuring the pressure of a vacuum pipeline of a single crystal furnace according to claim 1, characterized in that, The method for obtaining the adjusted pressure includes: Substituting the temperature compensation data into the ideal gas equation to obtain the adjusted pressure data.

9. The method for measuring the pressure of the vacuum pipeline of a single crystal furnace according to claim 1, wherein The method for obtaining the growth rate includes: Obtaining the crystal mass increase amount, crystal density, and growth interface area at each moment; Taking the ratio of the crystal mass increase amount at each moment to the growth duration as the mass growth rate; performing a negative correlation mapping on the product of the crystal density and the growth interface as the growth unit influence degree; Taking the product of the mass growth rate and the growth unit influence degree as the growth rate at each moment.

10. 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 the single crystal furnace vacuum pipeline pressure measurement method according to any one of claims 1 to 9.

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