Single crystal growth method, single crystal growth equipment and control device thereof

Abstract

The present invention provides a single crystal growth method, a single crystal growth device and a control device thereof, the method comprising: in a constant diameter growth stage, an initial function between the actual diameter of the crystal rod and time t is recorded as D=F0(t); when F0(t) meets a preset condition, the pulling rate of the crystal is locked, and the initial function is segmentedly corrected using the measurement results of the actual diameter of the crystal rod at n different measurement moments in succession to obtain a corrected segmented function D=F h (t), calculate the F at the corresponding moment h '(t), through F h '(t) / (A h *ω h ) is compared with the set value x to adjust the heating power in the single crystal furnace, thereby achieving precise control of the crystal rod diameter and reducing the fluctuation range of the actual diameter.

Description

Technical Field

[0001] The present invention relates to the field of crystal growth technology, and in particular to a single crystal growth method, single crystal growth equipment and a control device thereof. Background Art

[0002] To achieve perfect single crystal diameter growth, the growth rate must be locked, ensuring the crystal grows at the same set rate. When the crystal growth rate is locked, the diameter of the ingot is typically controlled by momentarily varying the heating power or temperature. This is achieved through temperature pulses (or power pulses).

[0003] However, due to the certain thermal hysteresis of heat transfer in the single crystal furnace, accurate control cannot be achieved during the regulation process, and it is difficult to precisely control the diameter of the crystal rod. The method for controlling the diameter of the crystal rod in the single crystal furnace needs to be improved. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a single crystal growth method and a single crystal growth device and a control device thereof. The single crystal growth method corrects the initial function and uses F h '(t) / (A h ω h ) is compared with the set value x to adjust the heating power in the single crystal furnace, thereby achieving precise control of the crystal rod diameter.

[0005] According to the single crystal growth method of the embodiment of the first aspect of the present invention, the method includes: in the equal diameter growth stage, the initial function between the theoretical diameter of the crystal rod and the time t is recorded as D=F0(t), F0(t)=A0*sin(ω0*t+Φ)+d, or, F0(t)=A0*cos(ω0*t+Φ)+d, d is the target diameter of the crystal rod, A0 is the initial amplitude, ω0 is the initial angular frequency, and Φ is the initial phase; when F0(t) meets the preset conditions, the pulling rate of the crystal is locked, and the initial function is segmentedly corrected using the measurement results of the actual diameter of the crystal rod at subsequent n different measurement moments to obtain the corrected segmented function D=F h (t), F h (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, D=F h(t) includes multiple sub-functions: the function between the actual diameter of the crystal rod at time t0 and time t is the initial function D=F0(t); the function between the actual diameter of the crystal rod after calibration at time t1 and time t is D=F1(t); and, t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z The moment is the zth measurement moment after the preset conditions are met, z is a positive integer and 2≤z≤n; calculate F′ at the corresponding moment h (t), if F' h (t) / (A h *ω h )≥ set value x, then increase the heating power and the increase is ΔP1; if F' h (t) / (A h *ω h )<0 and |F' h (t) / (A h *ω h )|≥ set value x, then reduce the heating power and the reduction amount is ΔP2, where A h 、ω h t h The amplitude and angular frequency at the moment are set to x>0. Among them, in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the corresponding parameter of the former measurement, and the other is obtained by calculation to achieve a correction.

[0006] According to the single crystal growth method of an embodiment of the present invention, by continuously correcting the parameters A and ω in the initial function, the function model can be adjusted more accurately, which is beneficial to improving the accuracy of the corrected function and making it better fit the actual data. The corrected function is more capable of timely reflecting the changing trend and speed of the actual diameter of the crystal rod at the current moment compared to the initial function. The corrected function can regulate the crystal rod, which can make the actual change of the crystal rod in the equal diameter stage relatively less volatile, which is beneficial to more stable fluctuations in the actual diameter of the crystal rod and is conducive to growing perfect crystals with uniform diameter.

[0007] In some embodiments, the initial function is segmentedly corrected using the measurement results of the actual diameter of the crystal rod at subsequent n different measurement moments, including: when F0(t) meets the preset conditions, the actual diameter D1 of the crystal rod at time t1 is measured for the first time, the corresponding parameter A1 is equal to the initial corresponding parameter A0, and ω1 is obtained by calculation to achieve a single correction; or, the corresponding parameter ω1 is equal to the initial corresponding parameter ω0, and A1 is obtained by calculation to achieve a single correction.

[0008] In some embodiments, during the p consecutive calibrations, at least one calibration is performed to calculate the parameter A, and at least one calibration is performed to calculate the parameter ω, where p is a positive integer and p≥2.

[0009] In some embodiments, in any two adjacent calibrations, one calibration is performed by calculating the parameter A, and the other calibration is performed by calculating the parameter ω.

[0010] In some embodiments, the constant diameter growth stage includes multiple sub-stages that are performed sequentially over time. The set values ​​x corresponding to the multiple sub-stages are different, and the set values ​​x of the multiple sub-stages decrease in chronological order.

[0011] In some embodiments, the current equal diameter length of the crystal rod is L, the target equal diameter length of the crystal rod is L', and when 100 mm ≤ L < 300 mm, x = x1, When 300mm≤L<L'-500mm, x=x2, When L'-500mm≤L≤L', x=x3, 0.01≤x3≤1 / 2, where L'≥1300mm.

[0012] In some embodiments, when 300 mm ≤ L < L' / 2, When L' / 2≤L<L'-500mm,

[0013] In some embodiments, when F0(t)=A0*sin(ω0*t+Φ)+d, the preset condition is F0(t)=d, and F′0(t)>0; when F0(t)=A0*cos(ω0*t+Φ)+d, the preset condition is F0(t)=d+A0.

[0014] In some embodiments, when F0(t) meets a preset condition, a measurement is performed every preset time, and the preset time is less than 1 minute.

[0015] In some embodiments, ΔP1=m1*|F′ h (t) / (A h *ω h )|, ΔP2=m2*|F' h (t) / (Ah *ω h )|, m1 and m2 are temperature control coefficients, 0 <m1≤15、0<m2≤15。

[0016] In some embodiments, the heating power is changed by a top heater on the upper side of the crucible, m1≤1, m2≤1; or, the heating power is changed by a side heater on the outer periphery of the crucible, 1≤m1≤5, 1≤m2≤5; or, the heating power is changed by a bottom heater on the lower side of the crucible, 5≤m1≤15, 5≤m2≤15.

[0017] In some embodiments, F' h (t) / (A h *ω h )<set value x, if F h (t)>d, and F′ h (t)>0, increase the actual liquid port distance; if F h (t)>d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)>0, increase the actual liquid port distance.

[0018] In some embodiments, the change in the crucible rising rate is Δv, Δv=|k*ΔD / Δt|, ΔD is the difference in crystal rod diameters between two adjacent measurement moments, and Δt is the time interval between two adjacent measurement moments, where 0.1≤k≤2.

[0019] In some embodiments, the actual liquid port distance fluctuates within a range of -5 mm to 5 mm with the target liquid port distance as the zero point.

[0020] According to the control device of the single crystal growth equipment of the embodiment of the second aspect of the present invention, it includes: a measuring mechanism, a data processing mechanism, a judgment mechanism and a power regulation mechanism, the measuring mechanism is used to measure the actual diameter D of the crystal rod, the data processing mechanism communicates with the measuring mechanism, and is used to simulate the initial function D=F0(t) between the actual diameter of the crystal rod and the time t, F0(t)=A0*sin(ω0*t+Φ)+d, or, F0(t)=A0*cos(ω0*t+Φ)+d, d is the target diameter of the crystal rod, A0 is the initial amplitude, ω0 is the initial angular frequency, Φ is the initial phase, the judgment mechanism is used to judge whether F0(t) meets the preset conditions, when F0(t) meets the preset conditions, the pulling rate of the crystal is locked, and the initial function is segmentedly corrected by using the measurement results of the actual diameter of the crystal rod at subsequent n different measurement moments in sequence to obtain the corrected segmented function D=F h (t), Fh (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, D=F h (t) includes multiple sub-functions: the function between the actual diameter of the crystal rod at time t0 and time t is the initial function D=F0(t); the function between the actual diameter of the crystal rod after calibration at time t1 and time t is D=F1(t); and, t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z At the zth measurement moment after the preset conditions are met, z is a positive integer and 2≤z≤n, the data processing mechanism is used to, in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the corresponding parameter of the previous measurement, and the other is obtained by calculation to achieve a correction, the power adjustment mechanism is used to adjust the heating power, and the judgment mechanism is also used to judge F' h (t) / (A h *ω h ) and the set value x, if F' h (t) / (A h *ω h )≥ set value x, the power regulating mechanism increases the heating power and the increase is ΔP1. If F' h (t) / (A h *ω h )<0 and |F' h (t) / (A h *ω h )|≥set value x, the power regulating mechanism reduces the heating power and the reduction amount is ΔP2.

[0021] According to an embodiment of the third aspect of the present invention, the single crystal growth equipment includes: a furnace body, a crucible, a heater and a control mechanism. The crucible is arranged in the furnace body and defines a holding space. The heater is arranged in the furnace body and is used to heat the crucible. The control device is the control device of the single crystal growth equipment according to the embodiment of the second aspect of the present invention. The power adjustment mechanism is used to adjust the power of the heater.

[0022] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0024] Figure 1 is a schematic flow chart of a single crystal growth method according to one embodiment of the present invention;

[0025] Figure 2 is a schematic flow chart of a single crystal growth method according to one embodiment of the present invention;

[0026] Figure 3 : is a simulation curve of the initial function between the actual diameter of the crystal ingot and time under preset conditions according to one embodiment of the present invention. The solid line represents the functional relationship before F0(t) meets the preset conditions, and the dotted line represents the corrected function after F0(t) meets the preset conditions.

[0027] Figure 4 is a corrected function between the actual diameter of the crystal ingot and time according to one embodiment of the present invention and a derivative of the corrected function;

[0028] Figure 5 is a curve showing a change in diameter of a crystal ingot after correction in combination with liquid-mouth distance control according to an embodiment of the present invention;

[0029] Figure 6 It is the fluctuation curve of the actual diameter of the lower crystal rod over time in the prior art;

[0030] Figure 7 is a fluctuation curve of the actual diameter of the crystal ingot over time, which is measured by controlling the diameter of the crystal ingot according to a corrected function according to one embodiment of the present invention;

[0031] Figure 8 It is a fluctuation curve of the actual diameter of the crystal rod and the heater power over time in the prior art. DETAILED DESCRIPTION

[0032] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings. The embodiments and features of the embodiments of the present invention may be combined with each other unless there is a conflict. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention, and are not to be construed as limiting the present invention.

[0033] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those skilled in the art will appreciate the applicability of other processes and / or the use of other materials.

[0034] In the present invention, unless otherwise specified, the following symbols have the following meanings: D is the actual diameter of the crystal rod, t is the time, D = F0 (t) is the initial function between the actual diameter of the crystal rod and the time, D = F h (t) is the corrected function between the actual ingot diameter and time, d is the target ingot diameter, A is the amplitude (specifically, the maximum difference between the actual ingot diameter D and the target ingot diameter d within one cycle), ω is the angular frequency, Φ is the initial phase, A0 is the initial amplitude, ω0 is the initial angular frequency, x is the set value, ΔP1 and ΔP2 are the changes in heating power, L is the current equal diameter length of the ingot, m1 and m2 are the temperature control coefficients, and Δv is the change in crucible rise rate. The term "perfect crystal" as used herein does not mean an absolutely perfect crystal or a crystal without any defects. Rather, it means that a very small amount of one or more defects is allowed, which is not sufficient to significantly change certain electrical or mechanical properties of the crystal or the resulting wafer, resulting in performance degradation of the electronic device.

[0035] Hereinafter, a method for growing a single crystal according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0036] like Figure 1 and Figure 2 As shown, the method of single crystal growth includes: in the isodiameter growth stage, the initial function between the actual diameter of the crystal rod and the time t is recorded as D = F0(t), F0(t) = A0*sin(ω0*t+Φ)+d (as shown in FIG. Figure 3 As shown in the figure), or, F0(t) = A0*cos(ω0*t+Φ)+d, where d is the target ingot diameter, A0 is the initial amplitude, ω0 is the initial angular frequency, Φ is the initial phase, and D is the actual ingot diameter. It can be seen that in the initial function F0(t), A0>0 and ω0>0.

[0037] When F0(t) meets the preset conditions, the pulling rate of the crystal is locked, and the initial function is piecewise corrected using the measurement results of the actual diameter of the crystal rod at the subsequent n different measurement moments to obtain the corrected piecewise function D=F h (t), Fh (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, where D = F h (t) includes multiple sub-functions: the function between the actual diameter of the crystal rod at time t0 and time t is the initial function D=F0(t); the function between the actual diameter of the crystal rod after calibration at time t1 and time t is D=F1(t); and, t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z The moment is the zth measurement moment after the preset conditions are met, z is a positive integer and 2≤z≤n, n is also a positive integer; calculate F′ at the corresponding moment h (t), if F' h (t) / (A h *ω h )≥ set value x, then increase the heating power and the increase is ΔP1; if F' h (t) / (A h *ω h )<0 and |F' h (t) / (A h *ω h )|≥ set value x(i.e. F' h (t) / (A h *ω h ) is greater than or equal to the set value x), the heating power is reduced by ΔP2, A h 、ω h t h The amplitude and angular frequency at the moment are set to x>0. Among them, in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the corresponding parameter of the former measurement, and the other is obtained by calculation to achieve a correction.

[0038] For example, taking the initial function F0(t)=A0*sin(ω0*t+Φ)+d as an example, A0, ω0 and Φ are all known. After F0(t) meets the preset conditions, the measurement result obtained by the subsequent first measurement is that the actual diameter of the crystal rod at time t1 is D1. The initial function is corrected using the above first measurement result to obtain the function D=F1(t) between the actual diameter D of the crystal rod at time t1 and time t; the measurement result obtained by the second measurement is that the actual diameter of the crystal rod at time t2 is D2. The initial function is corrected using the above second measurement result to obtain the function D=F2(t) between the actual diameter D of the crystal rod at time t2 and time t; the measurement result obtained by the third measurement is that the actual diameter of the crystal rod at time t3 is D3. The initial function is corrected using the above third measurement result to obtain the function D=F3(t) between the actual diameter D of the crystal rod at time t3 and time t; and so on. The measurement result obtained by the zth measurement is t z The actual diameter of the crystal rod at this moment is D z , use the zth measurement result to correct the initial function to obtain t z The function between the actual diameter D of the crystal rod at the moment and time t is D=F z (t); ...; the measurement result obtained by the nth measurement is t n The actual diameter of the crystal rod at this moment is D n , use the above nth measurement result to correct the initial function to obtain t n The function between the actual diameter D of the crystal rod at the moment and time t is D=F n (t).

[0039] It can be seen that the above-mentioned time t1, time t2, ..., t n The time is the time corresponding to a single measurement of the actual diameter of the crystal rod, t z-1 time and t z The moment can correspond to two adjacent measurements, so the piecewise function D=F after the initial function is piecewise corrected using the n measurement results in sequence h (t) may include:

[0040] At time t1, the function between the actual diameter of the crystal rod and time t is D = F1(t), F1(t) = A1*sin(ω1*t+Φ)+d;

[0041] At time t2, the function between the actual diameter of the crystal rod and time t is D = F2(t), F2(t) = A2*sin(ω2*t+Φ)+d;

[0042] At time t3, the function between the actual diameter of the crystal rod and time t is D = F3(t), F3(t) = A3*sin(ω3*t+Φ)+d;

[0043] …;

[0044] t z At this moment, the function between the actual diameter D of the crystal rod and time t is D=F z (t), F z (t) = A z *sin(ω z *t+Φ)+d;

[0045] …;

[0046] t n At this moment, the function between the actual diameter D of the crystal rod and time t is D=F n (t), F n (t) = A n *sin(ω n *t+Φ)+d.

[0047] Among them, A z >0,ω z >0. Considering that the function parameters differ little in the short term between two consecutive measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the corresponding parameter of the previous measurement, and the other is calculated to achieve a single correction. This facilitates the correction of the initial function while also making the corrected function more accurately reflect the change in the actual diameter of the crystal ingot over time. Thus, by establishing an initial function and then using multiple actual measurement results to perform segmented corrections on the initial function after it meets the preset conditions, the corrected function can more accurately reflect the change in the actual diameter of the crystal ingot over time, facilitating more timely regulation of the crystal ingot diameter using the corrected function.

[0048] For example, for the functions D=F1(t) and D=F2(t), there are two ways to correct A2 and ω2: First, take A2=A1, and ω2 is calculated by substituting the actual diameter D2 of the crystal rod measured at time t2 into the function F2(t), that is, ω2 is calculated by the equation D2=A2*sin(ω2*t+Φ)+d, and A2, D2, t2, Φ, and d are all known; Second, take ω2=ω1, and A2 is calculated by substituting the actual diameter D2 of the crystal rod measured at time t2 into the function F2(t), that is, A2 is calculated by the equation D2=A2*sin(ω2*t+Φ)+d, and ω2, D2, t2, Φ, and d are all known. Similarly, in any two subsequent adjacent measurements, for the function F z (t) = A z *sin(ω z *t+Φ)+d and function F z+1 (t) = A z+1 *sin(ω z+1 *t+Φ)+d: Φ is a constant, A z+1 and ωz+1 There are two correction methods: First, take A z+1 =A z , and ω z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substitute function F z+1 (t) is calculated, that is, ω z+1 By equation D z+1 =A z+1 *sin(ω z+1 *t+Φ)+d is calculated, A z+1 、D z+1 , t z+1 and Ф, d are all known; second, take ω z+1 =ω z , and A z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substitute function F z+1 (t) is calculated, that is, A z+1 By equation D z+1 =A z+1 *sin(ω z+1 *t+Φ)+d is calculated, ω z+1 、D z+1 , t z+1 and Ф, d are known.

[0049] Then use the corrected function to calculate the corrected function F at the corresponding moment h The first-order derivative F′ of (t) h (t), and according to F' h (t) / (A h *ω h ) value and the set value x to dynamically adjust the heating power. If F' h (t) / (A h *ω h )≥ set value x, indicating that the actual diameter of the crystal rod is in the rising period, and the actual diameter of the crystal rod is growing rapidly. At this time, increasing the heating power to suppress the growth of the actual diameter of the crystal rod is conducive to making the actual diameter of the crystal rod fluctuate towards the target diameter, and F' h (t) / (A h *ω h )<0 and |F' h (t) / (A h *ω h)|≥ the set value x, indicating that the actual diameter of the ingot is shrinking and decreasing rapidly. At this time, reducing the heating power to suppress the decrease in the actual diameter of the ingot helps to make the actual diameter of the ingot fluctuate toward the target diameter. As a result, during the constant diameter growth stage in actual production, the actual diameter of the ingot changes more smoothly and the fluctuation period is shorter. This helps improve the control accuracy of the actual ingot diameter and facilitates maintaining the stability of V / G during the constant diameter stage, thus promoting the growth of perfect crystals with uniform diameters. It can be seen that the use of the corrected function can achieve precise temperature control, which facilitates the actual control of the ingot diameter.

[0050] For example, after correcting the initial function D=F0(t), the function D=F1(t) at time t1 is obtained. At time t1 or from time t1 to time t2, F1'(t1) / (A1*ω1) is used to determine the adjustment of the heating power. F1'(t1) can be understood as the first derivative of the function F1(t) at time t1. Compared with the initial function, it can more accurately reflect the change trend of the diameter at the current moment and the speed of the change trend; after correction, the function D=F2(t) at time t2 is obtained. F'2(t2) / (A2*ω2) is used to determine the adjustment of the heating power. F′2(t2) can be understood as the first derivative of the function F′2(t) at time t2. Compared with the initial function, it can also more accurately reflect the change trend of the diameter at the current moment and the speed of the change trend; ...; After correction, t z Function of time D = F z (t), using F' z (t z ) / (A z *ω z ) to determine the adjustment of heating power, F′ z (t z ) can be understood as function F′ z (t) at t z The first derivative of the moment can more accurately reflect the change trend of the diameter at the current moment and the speed of the change trend than the initial function; and so on. At this time, calculate F' at the corresponding moment h (t) can be understood as calculating F h (t) The first derivative at the corresponding measurement time.

[0051] Of course, the embodiments of the present application are not limited to this. In some other examples, for time t1 to time t2 (i.e., t1≤t<t2), the corrected function is D=F1(t), and F1'(t1) / (A1*ω1) can be used to determine the adjustment of the heating power, or F1'(t y1 ) / (A1*ω1) to determine the adjustment of heating power, F1'(t y1 ) can be understood as the function F1(t) at t y1The first derivative at time t y1 The time is any moment between t1 and t2. Compared with the initial function, it can more accurately reflect the change trend of the diameter at the current moment and the speed of the change trend. For t2 to t3 (i.e., t2≤t<t3), the corrected function is D=F2(t). F′2(t2) / (A2*ω2) can be used to determine the adjustment of the heating power, and F'2(t y2 ) / (A2*ω2) to determine the adjustment of heating power, F'2(t y2 ) can be understood as the function F2(t) at t y2 The first derivative at time t y2 The time is any moment between t2 and t3. Compared with the initial function, it can more accurately reflect the change trend of the diameter at the current moment and the speed of the change trend; and so on. At this time, calculate F' at the corresponding moment h (t) can be understood as calculating F h (t) The first derivative at any moment between two adjacent measurement moments.

[0052] Of course, there are some examples where z Time to t z+1 Time (ie t z ≤t<t z+1 ), the corrected functions are all D=F z (t), you can also use F' z (t z ) / (A z *ω z ) to determine the adjustment of heating power.

[0053] The above examples all use F0(t) = A0*sin(ω0*t+Φ)+d for correction and optimization. In the application of trigonometric functions, the sine function and cosine function can be converted to each other through phase offset. Therefore, the derivation and optimization process for F0(t) = A0*cos(ω0*t+Φ)+d is similar to that for F0(t) = A0*sin(ω0*t+Φ)+d, and the detailed derivation process of F0(t) = A0*cos(ω0*t+Φ)+d is not repeated here.

[0054] It is understandable that after locking the pulling rate of the crystal, due to the complexity of the actual crystal growth situation, there is a certain difference between the actual diameter change of the crystal rod and the initial function. Specifically, when the pulling rate is locked, when the heater performs temperature (or power) pulse control on the diameter of the crystal rod, due to the certain thermal hysteresis of the heat transfer of the single crystal furnace, when the pulse signal is too large and maintained for too long, it will cause thermal shock and heat accumulation, which can easily lead to unstable diameter or even out-of-control diameter, and even polycrystallization of the crystal. If the pulse signal is too small or the time is too short, the control effect cannot be achieved. For example, the change of crystal rod diameter and heating power in some technologies is as follows: Figure 8 As shown, the horizontal axis is the equal diameter length of the crystal rod, and the vertical axis is the measured value of the crystal rod diameter. The target diameter of the crystal rod is 308mm. When the equal diameter length of the crystal rod is 715mm-725mm, the actual diameter of the crystal rod is measured to be 310mm, with a deviation of 2mm. At this time, the heater performs a temperature rise pulse. Due to thermal hysteresis and continuous growth of the crystal rod, heat acts on the position where the equal diameter length of the crystal rod is 735mm-745mm (the crystal growth speed corresponds to about 2 minutes for every 1mm length), resulting in the actual measured diameter of 304mm at the 745mm position, with a deviation of 4mm.

[0055] To this end, the above setting of the present application performs segmented correction on the initial function, and uses the corrected function as the basis for regulating the heating power, which can make corresponding regulatory measures on the diameter of the crystal rod more timely, thereby reducing the thermal hysteresis time and making the actual diameter fluctuation of the crystal rod more stable. Figure 6 and Figure 7 As shown, Figure 6 The inventors have made a curve showing the fluctuation of the diameter of the crystal rod over time during the actual growth process, in which the heating power is regulated according to a preset curve in the prior art. Figure 7 Based on the above-mentioned prior art, the inventors regulated the heating power based on a preset curve, and the measured diameter fluctuation curve of the crystal ingot during the actual growth process was plotted over time. As can be seen from the figure, the single crystal growth method of the present application can significantly make the actual diameter of the crystal ingot during the constant diameter stage more stable, and the fluctuation period is relatively short, which is conducive to improving the accuracy of controlling the actual diameter of the crystal ingot.

[0056] According to the single crystal growth method of an embodiment of the present invention, by continuously correcting the parameters A and ω in the initial function, the function model can be adjusted more accurately, which is beneficial to improving the accuracy of the corrected function and making it better fit the actual data. The corrected function is more capable of timely reflecting the changing trend and speed of the actual diameter of the crystal rod at the current moment compared to the initial function. The corrected function can regulate the crystal rod, which can make the actual change of the crystal rod in the equal diameter stage relatively less volatile, which is beneficial to more stable fluctuations in the actual diameter of the crystal rod and is conducive to growing perfect crystals with uniform diameter.

[0057] In some embodiments, during the constant diameter growth stage, the actual diameter of the crystal ingot is continuously collected within a preset time period to obtain the change of the actual diameter D of the crystal ingot with time t. In this case, multiple discrete data are obtained. By analyzing these discrete data, the range of diameter fluctuation can be obtained, and the periodic law of the change of the actual diameter of the crystal ingot with time can also be obtained. By fitting a sine function or a cosine function to these discrete data, the amplitude A0 and ω0 can be directly obtained from the fitting results, thereby obtaining A0 and ω0 that conform to the diameter change law, and thus simulating the initial function F0(t) from the multiple discrete data. The start time and end time of the preset time period can be selected according to actual needs. For example, the start time of the constant diameter stage can be the start time of the preset time period. The preset time period can be 1 hour to 2 hours, but is not limited to this. Of course, the preset time period can also end when the initial function fluctuates relatively evenly above and below the target diameter (that is, the actual diameter of the crystal ingot measured multiple times is partially larger than the target diameter and partially smaller than the target diameter). Then, it is determined whether F0(t) meets the preset conditions. Of course, the time when F0(t) meets the preset conditions can also be the end time of the preset time period.

[0058] Among them, when F0(t) meets the preset conditions, if the current time t0 corresponds to a single measurement time, that is, the actual diameter of the crystal rod is measured at time t0, or if the current time t0 does not correspond to a single measurement time, that is, the actual diameter of the crystal rod is not measured at time t0, then the actual diameter of the crystal rod corresponding to the current time t0 can be directly calculated by the initial function.

[0059] In some embodiments, the initial function is piecewise corrected using the measurement results of the actual diameter of the crystal ingot at n different subsequent measurement moments, including: when F0(t) meets the preset conditions, the actual diameter D1 of the crystal ingot at time t1 is measured for the first time, the corresponding parameter A1 is equal to the initial corresponding parameter A0, and ω1 is obtained by calculation to achieve a single correction. Of course, in some other embodiments, the initial function is piecewise corrected using the measurement results of the actual diameter of the crystal ingot at n different subsequent measurement moments, including: when F0(t) meets the preset conditions, the actual diameter D1 of the crystal ingot at time t1 is measured for the first time, the corresponding parameter ω1 is equal to the initial corresponding parameter ω0, and A1 is obtained by calculation to achieve a single correction.

[0060] Therefore, the function D=F1(t) between the actual diameter of the crystal rod at time t1 and the time t is obtained, which is convenient for simplifying the correction of the function while more timely and accurately reflecting the change of the actual diameter of the crystal rod, and is convenient for making the subsequent functions F2(t), F3(t), ..., F n The acquisition of (t) can also better and more timely reflect the actual diameter change of the crystal rod, which is conducive to enhancing the stability of the system.

[0061] In some embodiments, during the p consecutive calibrations, at least one calibration is performed by calculating the parameter A, and at least one calibration is performed by calculating the parameter ω, where p is a positive integer and p ≥ 2. That is, during the p consecutive calibrations, not all parameters A and ω are calculated and corrected. This helps to improve the error caused by correcting only one parameter p times while increasing the other parameter, reduces error accumulation, and allows for more precise adjustment of the function model. This helps to improve the accuracy of the parameters A and ω of the corrected function, allowing it to better fit actual data, so that the corrected function more promptly and accurately reflects changes in the ingot diameter compared to the initial function.

[0062] For example, from the function F z (t) = A z *sin(ω z *t+Φ)+d to F z+p (t) = A z+p *sin(ω z+p *t+Φ)+d, it is calibrated p times continuously, for example, F z (t) to F z+2 (t) After 2 calibrations, F z (t) to F z+3 (t) After 3 corrections, among the p corrections, at least one correction is performed to calculate the parameter A through the equation, and at least one correction is performed to calculate the parameter ω through the equation. The number of corrections corresponding to the calculation of the parameter A through the equation and the number of corrections corresponding to the calculation of the parameter ω through the equation may be equal or different.

[0063] Take the initial function F0(t)=A0*sin(ω0*t+Φ)+d as an example:

[0064] (1) If p = 2, the function F z (t) = A z *sin(ω z *t+Φ)+d to F z+2 (t) = A z+2 *sin(ω z+2 *t+Φ)+d, one of the following correction methods can be used: First, from the function F z (t) Corrected to function F z+1 (t), take A z+1 =A z ,ω z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take ωz+2 =ω z+1 , A z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substitute into the equation and calculate; Second, the self function F z (t) Corrected to function F z+1 (t), take ω z+1 =ω z , A z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take A z+2 =A z+1 ,ω z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substitute into the equation and calculate;

[0065] (2) If p = 3, the self function F z (t) = A z *sin(ω z *t+Φ)+d to F z+3 (t) = A z+3 *sin(ω z+3 *t+Φ)+d, one of the following correction methods can be used: First, from the function F z (t) Corrected to function F z+1 (t), take A z+1 =A z ,ω z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take ω z+2 =ω z+1 , A z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take ω z+3 =ω z+2 , A z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate; Second, the self function F z (t) Corrected to function Fz+1 (t), take A z+1 =A z ,ω z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take ω z+2 =ω z+1 , A z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take A z+3 =A z+2 ,ω z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate; Third, the self-function F z (t) Corrected to function F z+1 (t), take A z+1 =A z ,ω z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take A z+2 =A z+1 ,ω z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take ω z+3 =ω z+2 , A z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate; Fourth, the self-function F z (t) Corrected to function F z+1 (t), take ω z+1 =ω z , A z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take Az+2 =A z+1 ,ω z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take A z+3 =A z+2 ,ω z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate; Fifth, the self-function F z (t) Corrected to function F z+1 (t), take ω z+1 =ω z , A z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take A z+2 =A z+1 ,ω z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take ω z+3 =ω z+2 , A z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate; Sixth, from the function F z (t) Corrected to function F z+1 (t), take ω z+1 =ω z , A z+1 By adding t z+1 The actual diameter D of the crystal rod measured at the moment z+1 Substituting into the equation, we can calculate that the function F z+1 (t) Corrected to function F z+2 (t), take ω z+2 =ω z+1 , A z+2 By adding t z+2 The actual diameter D of the crystal rod measured at the moment z+2 Substituting into the equation, we can calculate that the function F z+2 (t) Corrected to function F z+3 (t), take A z+3 =Az+2 ,ω z+3 By adding t z+3 The actual diameter D of the crystal rod measured at the moment z+3 Substitute into the equation and calculate.

[0066] It should be noted that this demonstrates only a specific sequence of two and three consecutive corrections. However, in practice, the order and number of corrections can be adjusted based on the specific data characteristics and optimization requirements. The key is to ensure that both parameters A and ω are fully updated throughout the optimization process to improve the accuracy and reliability of the function model. In other words, p can be any positive integer greater than or equal to 2, for example, 4, 5, or even more.

[0067] In some embodiments, between any two consecutive calibrations, one calibration is performed to calculate parameter A, while the other calibration is performed to calculate parameter ω. By alternately fixing and updating parameters A and ω, the corrected function can be made to more closely resemble the actual crystal growth process. Each iteration is fine-tuned based on the results of the previous iteration, thereby reducing error accumulation and improving the reliability of the function.

[0068] For example, the parameter A or the parameter ω obtained by calculation in the previous calibration is directly substituted into the next calibration calculation, that is, for the function F z (t) = A z *sin(ω z *t+Φ)+d, function F z+1 (t) = A z+1 *sin(ω z+1 *t+Φ)+d and function F z+2 (t) = A z+2 *sin(ω z+2 *t+Φ)+d: If A z+1 =A z ,ω z+1 By calculation, we can take ω z+2 =ω z+1 , A z+2 By calculation, if ω z+1 =ω z , A z+1 By calculation, we can take A z+2 =A z+1 ,ω z+2 Whether the parameter A or ω is substituted first for the correction calculation, as long as the principle of alternating updates is maintained and each update is ensured to be based on the latest measurement data and the results of the previous iteration, it will be beneficial to further improve the reliability and accuracy of the corrected function.

[0069] In some embodiments, the isodiametric growth stage includes multiple sub-stages that proceed sequentially over time, and the set values ​​x corresponding to the multiple sub-stages are different, and the set values ​​x of the multiple sub-stages decrease in chronological order. During the isodiametric growth stage of the crystal rod, as its isodiametric length gradually increases, the thermal hysteresis time also changes accordingly. The longer the isodiametric length, the shorter the thermal hysteresis time. In order to accurately match this dynamic change, an intelligent control strategy is adopted, that is, according to the different ranges of the isodiametric length of the crystal rod, it is subdivided into multiple sub-stages, and an exclusive set value x is set for each sub-stage, that is, the temperature pulse start-up conditions of each sub-stage are different, and the temperature pulse generation conditions of each area are different. These set values ​​are adjusted step by step with the increase of the isodiametric length. The heating conditions can be flexibly adjusted to adapt to the changes in the thermal hysteresis time, thereby ensuring the stability of the crystal rod growth process and achieving more precise heating control.

[0070] In some embodiments, the current equal diameter length of the crystal rod is L, the target equal diameter length of the crystal rod is L', and when 100 mm ≤ L < 300 mm, x = x1, When 300mm≤L<L'-500mm, x=x2, When L'-500mm≤L≤L', x=x3, 0.01≤x3≤1 / 2, where L'≥1300mm. The initial function may be a sine function or a cosine function.

[0071] For example, assuming that the target equal diameter length of the crystal rod is L' = 2000mm, and the actual equal diameter length of the crystal rod is between 0≤L<100mm, in the early stage of equal diameter crystallization, the protective gas (such as argon) and the water cooling jacket in the crystal growth equipment have a more severe impact on the crystal, and the actual diameter of the crystal rod fluctuates greatly. At this time, it is difficult to lock the pulling rate of the crystal; in the early stage of equal diameter, when the current equal diameter length L of the crystal rod is between 100mm≤L<300mm, x=x1, In the initial stage of equal diameter, there is more liquid melt, the thermal hysteresis time is longer, and the temperature response caused by the change of heating power is relatively delayed. Therefore, the temperature pulse should not be too long, and a shorter temperature control time is required. At this time, |F' h (t) / (A h *ω h )|≥x1, turn on temperature control, that is, F' h (t) / (A h *ω h )≥x1, increase the heating power, and F' h (t) / (A h *ω h )<0 and |F' h (t) / (A h *ω h)|≥x1, reduce the heating power; with the increase of the equal diameter length, the growth tends to be stable. In the middle of the equal diameter stage, when the current equal diameter length of the crystal rod is 300mm≤L<1500mm, the thermal hysteresis time is relatively shortened, x=x2, At this time |F' h (t) / (A h *ω h )|≥x2, temperature control is turned on, that is, F′ h (t) / (A h *ω h )≥x2, increase the heating power, and F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥x2, reduce the heating power; in the later stage of equal diameter, when the current equal diameter length of the crystal rod is 1500mm≤L≤2000mm, the melt is further reduced, the remaining melt is small, the thermal hysteresis time is short, and the temperature control intervention time can be extended. At this time, x=x3, 0.01≤x3≤1 / 2, at this time |F′ h (t) / (A h *ω h )|≥x3 to turn on temperature control, that is, F′ h (t) / (A h *ω h )≥x3, increase the heating power, and F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥x3, the heating power is reduced; this allows for longer temperature control without causing excessive heat accumulation. By adjusting the setpoint corresponding to the ingot's constant diameter length, intelligent adjustment of the temperature control conditions is achieved, effectively avoiding the adverse effects of heat accumulation. It can be understood that changing the heating power during the constant diameter growth stage can be understood as applying a temperature pulse, and the duration of the temperature pulse can be understood as the duration of the change in heating power.

[0072] Of course, the constant diameter growth stage can also be divided into two sub-stages, three sub-stages or more than four sub-stages. As the crystal ingot grows, the temperature control conditions change to adapt to the changes in the growth of the crystal ingot.

[0073] In some embodiments, when 300 mm ≤ L < L' / 2, When L' / 2≤L<L'-500mm, It can be seen that in the middle stage of equal diameter, the growth tends to be stable. When the equal diameter length is 300mm≤L<L'-500mm, x=x2, x2 can be further subdivided to improve the quality and growth efficiency of the crystal rod.

[0074] For example, assuming the target equal diameter length of the crystal ingot is L' = 2000mm, when the current equal diameter length of the crystal ingot is 300≤L<1000mm, the thermal hysteresis time is relatively shortened, x = x2, At this time |F′ h (t) / (A h *ω h )|≥x2, temperature control is turned on, that is, F′ h (t) / (A h *ω h )≥x2, increase the heating power, and F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥x2, reduce the heating power; with the increase of the equal diameter length, the growth becomes more stable. The current equal diameter length of the crystal rod is 1000mm≤L<1500mm. In this sub-stage, the diameter of the crystal rod is more stable, the melt is steadily reduced, and the thermal hysteresis time is further shortened. x=x2, |F′ h (t) / (A h *ω h )|≥x2 to turn on temperature control, that is, F′ h (t) / (A h *ω h )≥x2, increase the heating power, and F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥x2, the heating power is reduced. By further subdividing the range of x2, the heating power and other parameters can be adjusted more precisely to accommodate subtle changes during ingot growth, helping to reduce fluctuations during ingot growth and thus improving the uniformity and consistency of the ingot. Optionally, the time period corresponding to L < L' / 10 can be used as the preset time period described throughout this article to construct the initial function.

[0075] In some embodiments, when F0(t)=A0*sin(ω0*t+Φ)+d, the preset condition is F0(t)=d, and F′0(t)>0; when F0(t)=A0*cos(ω0*t+Φ)+d, the preset condition is F0(t)=d+A0. It can be seen that when F0(t)=A0*sin(ω0*t+Φ)+d, the preset condition is F0(t)=d, and F′0(t)>0, which ensures that the actual diameter D of the crystal rod at a certain time t is equal to the target diameter d, and the initial phase is 0, that is, Φ=0. At this time, Figure 3 As shown, the initial function between the actual diameter of the crystal rod and time is D=F0(t), F0(t)=A0*sin(ω0*t)+d, and when the preset conditions are met, it indicates that the actual diameter D of the crystal rod is increasing with time t, which is convenient for correction from the initial position of a fluctuation cycle of the initial function, simplifies the correction, and reduces the difficulty of calculation; when F0(t)=A0*cos(ω0*t+Φ)+d, the preset condition is F0(t)=d+A0, so that when the crystal rod meets the preset conditions, the actual diameter of the crystal rod is equal to the maximum value of the fluctuation relative to the target diameter d. At this time, the initial function is at the peak value and the initial phase is 0, that is, Φ=0, that is, F0(t)=A0*cos(ω0*t)+d, and the parameters A and ω can be corrected subsequently. The simplified initial function makes the subsequent data processing and correction process easier to operate, and is convenient for correction from the initial position of a fluctuation cycle of the initial function, simplifies the correction, and reduces the difficulty of calculation. Obviously, the above setting is conducive to reducing the error easily caused in the subsequent calibration process due to the initial phase Φ≠0 during the calibration process, and is conducive to further improving the calibration accuracy.

[0076] Of course, the preset conditions can also be other conditions. Under these conditions, the initial phase of the initial function is not zero, that is, Φ≠0, and subsequent correction calculations of the initial function can also be performed. Optionally, the initial phase Φ can be calculated when the initial function D=F0(t) is simulated. Alternatively, the initial phase Φ can be calculated based on the actual diameter of the crystal ingot at the current moment when the preset conditions are met. Regardless of the method used to determine the initial phase Φ, Φ can be zero or non-zero.

[0077] In some embodiments, after F(t) meets the preset conditions, measurements are taken at preset intervals, where the preset interval is less than 1 minute. During the growth of the ingot, the growth rate is generally about 1 mm / min. Therefore, during adjacent measurements on both sides, the preset interval is less than 1 minute, so that the time interval between adjacent measurements on both sides has a good adaptability to the growth rate. It is not easy for large errors to accumulate in the corresponding parameters between two measurements due to too long a measurement interval. These errors will gradually accumulate and affect the accuracy of the correction function and the control precision of the system, and further affect the quality of the final product. High-frequency measurements help reduce such error accumulation and improve the stability and reliability of the system.

[0078] Optionally, the preset interval is less than 10 s, which can capture subtle changes in diameter more timely, enabling the system to respond and adjust faster. With the increase in the measurement frequency, the system can obtain more real-time data points for correction calculations and make more accurate control adjustments based on this, thereby reducing the fluctuation range of the actual diameter of the ingot.

[0079] Furthermore, when the preset interval is 1 s, real-time monitoring of the growth process is achieved, and any minute change in the diameter of the ingot can be captured immediately. Through an almost continuous data stream, the system can more accurately evaluate the change trend of the diameter and make more minute adjustments to maintain the stability of the diameter. High-frequency measurements and a fast feedback mechanism help enhance the overall stability of the system and reduce fluctuations and deviations caused by external interference.

[0080] In some embodiments, ΔP1 = m1 * |F′ h (t) / (A h *ω h )|, ΔP2 = m2 * |F′ h (t) / (A h *ω h )|, where both m1 and m2 are temperature control coefficients, 0 < m1 ≤ 15, 0 < m2 ≤ 15. Due to differences in the heat field insulation performance, heater capabilities, etc., the temperature control coefficients are different. For example, for a heat field with poor insulation performance, a larger temperature control coefficient is required so that more heat can act on the melt.

[0081] It can be seen that ΔP1 = m1 * |F′ h (t) / (A h *ω h )| represents the amount of heating power that the system needs to increase when the diameter is increasing, and ΔP2 = m2 * |F′ h (t) / (A h *ω h)| indicates the amount of heating power that the system needs to reduce when the diameter is decreasing. The increase in heating power is positively correlated with the actual diameter growth rate of the crystal ingot, and the decrease in heating power is positively correlated with the actual diameter reduction rate of the crystal ingot. By associating the adjustment amount of heating power with the absolute value of the diameter change rate, it is convenient to make the temperature pulse more closely match the fluctuation of the actual diameter of the crystal ingot. The system can more accurately control the stability of the diameter. When the diameter deviates from the target value, the system can immediately adjust the heating power according to the degree and direction of the deviation, thereby quickly restoring the crystal ingot to a state of constant diameter growth, which helps to reduce the fluctuation range of the diameter and improve the stability and consistency of the growth process.

[0082] It can be understood that the change in heating power can be controlled by any one or more heaters of the single crystal growth equipment.

[0083] In some embodiments, the heating power is changed by a top heater on the upper side of the crucible, m1≤1, m2≤1, for example, m1 and m2 are 0.2, 0.5, 0.7 or 1, etc.; or, the heating power is changed by a side heater on the outer periphery of the crucible, 1≤m1≤5, 1≤m2≤5, for example, m1 and m2 are 1.2, 2.5, 3.7, 4.3 or 5, etc.; or, the heating power is changed by a bottom heater on the lower side of the crucible, 5≤m1≤15, 5≤m2≤15, for example, m1 and m2 are 5.8, 6.5, 7.7, 8.3, 9, 11, 13, 14 or 15, etc. When the same temperature pulse is required, different heaters are set at different positions and at different distances from the crystal rod. Therefore, different heaters have different corresponding thermal hysteresis. Different heaters can be used to change the heating power to meet the actual needs of the crystal rod. Different heater settings correspond to different temperature control coefficients, so that after the corresponding heater changes the heating power, the temperature pulse brought about by it can be more closely matched with the temperature pulse required to control the actual diameter change of the crystal rod. The system can select the most suitable heater and adjustment strategy based on the current actual diameter of the crystal rod and the target diameter of the crystal rod. This flexibility helps to optimize the growth process and improve the quality and production efficiency of the crystal rod.

[0084] It is understood that if the single crystal growth apparatus includes a top heater, the top heater is relatively close to the solid-liquid interface of the melt in the crucible. The top heater plays a dominant role in adjusting the heating power, ensuring efficient heat transfer and enabling the top heater to directly influence the overall growth process of the crystal ingot. If the single crystal growth apparatus includes a bottom heater, the bottom heater is relatively far from the solid-liquid interface of the melt in the crucible. To this end, the above-mentioned configuration of the present application matches and corresponds the temperature control coefficients of the different heaters to meet the crystal ingot control requirements.

[0085] It can be understood that in the process of controlling the diameter of the crystal rod, as long as the corresponding heating power can be met, one of these three heaters or a random combination of these three heaters can be used to synergistically control the temperature change without affecting the growth process of the crystal rod.

[0086] In some embodiments, as Figure 2 As shown, F′ h (t) / (A h *ω h )<set value x, the actual diameter change rate of the crystal rod is small, and the diameter is basically in the peak area. To prevent diameter deviation, the diameter is controlled by the liquid nozzle distance. It can be adjusted in the following different situations:

[0087] First, if F h (t)>d, and F′ h (t)>0, increase the actual liquid mouth distance. At this time, the actual diameter of the crystal rod is larger than the target diameter of the crystal rod, the rate of change of the actual diameter of the crystal rod is positive, the actual diameter of the crystal rod is still increasing, and is basically in the diameter peak area. At this time, the actual liquid mouth distance can be increased to change the rate of change of the actual diameter of the crystal rod, so that the rate of change of the actual diameter of the crystal rod can be reduced from a positive value or changed to a negative value. The actual diameter of the crystal rod gradually decreases and approaches the target diameter of the crystal rod, thereby ensuring the stability of the crystal rod diameter during the production process.

[0088] Second, if F′ h (t)>0, and F′ h (t)<0, reduce the actual liquid mouth distance, at this time the actual diameter of the crystal rod is larger than the target diameter of the crystal rod, the rate of change of the actual diameter of the crystal rod is negative, the actual diameter of the crystal rod is constantly decreasing, and by reducing the actual liquid mouth distance, the rate of change of the actual diameter of the crystal rod is changed, so that the actual diameter of the crystal rod is not easily excessively reduced to be too smaller than the target diameter of the crystal rod; illustratively, by adjusting the rising rate of the crucible and the pulling rate of the seed crystal at the same time, the system can achieve fine control of the growth rate and diameter of the crystal rod, ensuring that the actual diameter of the crystal rod can gradually approach and stabilize within the range of the target diameter of the crystal rod, the pulling rate of the seed crystal is the pulling rate of the crystal, and the initial adjustment of the seed crystal pulling rate can be adjusted based on the crystal pulling rate locked when F(t) meets the preset conditions, and the subsequent adjustment of the seed crystal pulling rate can be adjusted based on the current moment.

[0089] It can be understood that in the process of reducing the actual liquid mouth distance, in order to prevent the liquid level of the melt in the crucible from exceeding the solid-liquid interface, the above-mentioned setting of the present application changes the seed crystal pulling rate so that the liquid level of the melt will not exceed the solid-liquid interface while reducing the actual liquid mouth distance, which is beneficial to reducing the risk of crystal rod breakage.

[0090] Third, if F h (t)<d, and F′h (t)<0, reduce the actual liquid nozzle distance. At this time, the actual diameter of the crystal rod is smaller than the target diameter of the crystal rod, and the rate of change of the actual diameter of the crystal rod is negative. The actual diameter of the crystal rod is constantly decreasing. By reducing the actual liquid nozzle distance, the rate of change of the actual diameter of the crystal rod is changed. The rate of change of the actual diameter of the crystal rod increases from a negative value or increases to a positive value, so that the actual diameter of the crystal rod continues to increase and gradually approaches the target diameter of the crystal rod, ensuring the stability of the crystal rod diameter during the production process.

[0091] Fourth, if F h (t)<d, and F′ h (t)>0, increase the actual liquid nozzle distance. At this time, the actual diameter of the crystal rod is smaller than the target diameter of the crystal rod. The rate of change of the actual diameter of the crystal rod is positive, and the actual diameter of the crystal rod is constantly increasing. By decreasing and increasing the actual liquid nozzle distance, the rate of change of the actual diameter of the crystal rod is reduced, which makes it easier for the actual diameter of the crystal rod to continue to increase, and it is not easy to increase to a value that is too large than the target diameter of the crystal rod, thereby ensuring the stability of the crystal rod diameter during the production process.

[0092] The liquid nozzle distance is the distance between the lower end of the guide tube and the solid-liquid interface. By adjusting the liquid nozzle distance, the temperature gradient in the melt can be adjusted, thereby affecting the growth rate of the crystal rod.

[0093] It can be seen that the liquid nozzle distance can be changed by adjusting the crucible's rising rate and the seed crystal pulling rate. The actual diameter of the crystal ingot is controlled by both temperature pulse control and liquid nozzle distance control. This ensures that the actual diameter of the crystal ingot fluctuates within the target diameter range throughout the growth process, with the fluctuation amplitude and fluctuation period being reduced, achieving a faster control response. In addition, by simultaneously adjusting the crucible's rising rate and the seed crystal pulling rate, the relative position of the crystal ingot and the melt liquid level remains unchanged.

[0094] It can be understood that the "changing of the crucible rising rate" and "changing of the seed crystal pulling rate" in the above scheme of the present application are both adjusted directly based on the current moment. For example, at the current moment, the crucible rising rate is v. If the crucible rising rate needs to be increased, and the increase is Δv, then the crucible rising rate is directly increased from v to the target rising rate v+Δv. Similarly, if the crucible rising rate needs to be reduced, and the reduction is Δv, then the crucible rising rate is directly reduced from v to the target rising rate v-Δv. Obviously, when v-Δv>0, the crucible is still in an ascending state; if v-Δv<0, the crucible is in a descending state. In addition, when the liquid mouth distance is used to control the actual diameter of the crystal rod, the heating power can be controlled according to a preset curve. The setting of the preset curve is well known to those skilled in the art and will not be described in detail here.

[0095] Optionally, F′ hThe relationship between (t) and 0 can be determined by the results of two consecutive measurements. If the actual diameter of the crystal rod obtained in the latter measurement is larger than that obtained in the previous measurement, then F′ h (t)>0, if the actual diameter of the crystal rod obtained by the latter measurement is larger than the actual diameter of the crystal rod obtained by the previous measurement, then F′ h (t) < 0. Of course, the judgment can also be made by directly taking the derivative of the corrected function.

[0096] In some embodiments, the change in the crucible rising rate is Δv, Δv=|k*ΔD / Δt|, ΔD is the difference in the diameter of the crystal rod between two adjacent measurement moments, and Δt is the time interval between two adjacent measurement moments, for example, ΔD / Δt=(D z+1 -D z ) / (t z+1 -t z ), where 0.1≤k≤2. Therefore, the rate of change of the crucible's rising speed is positively correlated with |ΔD / Δt|, which is the absolute value of the ratio of the difference between the actual diameters of the crystal ingot measured between two adjacent measurements to the time interval between the two corresponding measurements. That is, the greater the difference between the actual diameters of the crystal ingot measured between two adjacent measurements, the greater the change in the crucible's rising speed, facilitating timely adjustment and control of the crystal ingot diameter.

[0097] For example, k can be 0.1, 0.5, 0.8, 1, 1.3, 1.6, 1.8, or 2, etc.

[0098] In some embodiments, the actual liquid mouth distance fluctuates within the range of -5mm to 5mm with the target liquid mouth distance as the zero point. The setting of the target liquid mouth distance has process requirements in the crystal rod preparation process, which can ensure the relative stability of factors such as the temperature gradient and melt during the crystal growth process. The target liquid mouth distance needs to be maintained within a relatively stable range. When the liquid mouth distance is controlled by changing the crucible rising speed, it is necessary to ensure that the actual liquid mouth distance fluctuates within the range of the target liquid mouth distance and does not significantly affect the V / G value, thereby achieving the stability of the crystal rod growth process and improving production efficiency. In other words, the process of reducing the actual liquid mouth distance in the above scheme will not reduce the actual liquid mouth distance to a value less than the minimum value of the actual liquid mouth distance. Similarly, the process of increasing the actual liquid mouth distance will not increase the actual liquid mouth distance to a value exceeding the maximum value of the actual liquid mouth distance.

[0099] It can be understood that based on the fluctuation of the actual diameter of the crystal rod, the adjustment of the actual liquid nozzle distance also fluctuates to a certain extent. Therefore, in the two adjacent processes of increasing the actual liquid nozzle distance and decreasing the actual liquid nozzle distance, regardless of the order of the two processes, when the adjustment of the two processes is completed, the actual liquid nozzle distance tends to be adjusted to the target liquid nozzle distance.

[0100] A control device for single crystal growth equipment according to an embodiment of the present invention includes a measuring mechanism, a data processing mechanism, a judgment mechanism, and a power regulation mechanism. The measuring mechanism is used to measure the actual diameter D of the crystal ingot in real time and accurately, providing basic data for subsequent data processing and judgment.

[0101] The data processing mechanism communicates with the measuring mechanism, and the data processing mechanism is used to construct an initial function D=F0(t) between the actual diameter of the crystal rod and time t, F0(t)=A0*sin(ω0*t+Φ)+d, or F0(t)=A0*cos(ω0*t+Φ)+d, where d is the target diameter of the crystal rod, A0 is the initial amplitude, ω0 is the initial angular frequency, and Φ is the initial phase, which can intuitively reflect the changing trend of the crystal rod diameter over time.

[0102] The judgment mechanism is used to judge whether F0(t) meets the preset conditions. When F0(t) meets the preset conditions, the pulling rate of the crystal is locked. The data processing mechanism uses the measurement results of the actual diameter of the crystal rod at the subsequent n different measurement moments to perform segmented correction on the initial function to obtain the corrected segmented function D=F h (t), F h (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, D=F h (t) includes multiple sub-functions: the function between the actual diameter of the crystal rod at time t0 and time t is the initial function D=F0(t); the function between the actual diameter of the crystal rod after calibration at time t1 and time t is D=F1(t); and, t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z The time is the zth measurement time after the preset condition is met, where z is a positive integer and 2≤z≤n; the data processing mechanism is used to realize a correction in which, in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the parameter corresponding to the former measurement, and the other is obtained by calculation.

[0103] The power adjustment mechanism is used to adjust the heating power, and the judgment mechanism is also used to judge F' h (t) / (A h *ω h ) and the set value x, if F′ h (t) / (A h *ω h )≥ set value x, the power regulating mechanism increases the heating power and the increase is ΔP1. If F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥ set value x, the power adjustment mechanism reduces the heating power and the reduction amount is ΔP2, by judging F′ h (t) / (A h *ω h ) and the set value x, accurately adjusting the heating power to achieve fine control of the crystal rod diameter is beneficial to making the actual diameter of the crystal rod fluctuate towards the target diameter. As a result, in the actual production process, the actual diameter of the crystal rod in the equal diameter stage tends to change more smoothly, and the fluctuation period is shorter, which is beneficial to improving the control accuracy of the actual diameter of the crystal rod.

[0104] In some embodiments, the data processing mechanism sequentially uses the measurement results of the actual diameter of the crystal ingot at n different subsequent measurement times to perform a piecewise correction on the initial function. In this case, the data processing mechanism is configured such that: when F0(t) satisfies a preset condition, the actual diameter D1 of the crystal ingot at time t1 is measured for the first time, and the corresponding parameter A1 is equal to the initial corresponding parameter A0, and ω1 is calculated to achieve a single correction; or the judgment mechanism is configured such that: when F0(t) satisfies a preset condition, the actual diameter D1 of the crystal ingot at time t1 is measured for the first time, and the corresponding parameter ω1 is equal to the initial corresponding parameter ω0, and A1 is calculated to achieve a single correction.

[0105] In some embodiments, the data processing mechanism is configured such that, in p consecutive corrections, at least one correction is performed to calculate the parameter A, and at least one correction is performed to calculate the parameter ω, where p is a positive integer and p≥2.

[0106] In some embodiments, the determination mechanism is used to determine whether F0(t) satisfies a preset condition. When F0(t) = A0*sin(ω0*t+Φ)+d, the preset condition is F0(t) = d, and F′0(t) > 0. When F0(t) = A0*cos(ω0*t+Φ)+d, the preset condition is F0(t) = d+A0. In some embodiments, after the determination mechanism determines that F0(t) satisfies the preset condition, the measurement mechanism performs a measurement at a preset interval, where the preset interval is less than 1 minute.

[0107] In some embodiments, the data processing mechanism is configured such that, in any two adjacent corrections, one correction is performed to calculate the parameter A, and the other correction is performed to calculate the parameter ω.

[0108] In some embodiments, the power regulation mechanism is configured as follows: ΔP1 = m1*|F′ h (t) / (A h *ω h )|, ΔP2=m2*|F′ h (t) / (A h *ω h )|, m1 and m2 are temperature control coefficients, 0 <m1≤15、0<m2≤15。

[0109] In some embodiments, the control device further includes a driving mechanism for driving the crucible to rise and fall, and the driving mechanism communicates with the judgment mechanism to control the crucible to rise and fall according to the judgment mechanism. h (t) / (A h *ω h )<set value x: If the judgment mechanism further determines that F h (t)>d, and F′ h (t)>0, increase the actual liquid port distance; if F h (t)>d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)>0, increase the actual liquid port distance.

[0110] In some embodiments, the driving mechanism is configured such that the change in the crucible rising rate is Δv, Δv=|k*ΔD / Δt|, ΔD is the difference in crystal rod diameters between two adjacent measurement moments, and Δt is the time interval between two adjacent measurement moments, where 0.1≤k≤2.

[0111] In some embodiments, the driving mechanism is configured such that the driving mechanism drives the crucible to rise and fall to change the actual liquid port distance, and the actual liquid port distance fluctuates within a range of -5 mm to 5 mm with the target liquid port distance as the zero point.

[0112] According to an embodiment of the present invention, a single crystal growth apparatus comprises a furnace, a crucible, a heater, and a control mechanism. The furnace provides a stable, enclosed environment for ingot growth, helping to create a stable thermal field while minimizing the effects of temperature fluctuations, impurity contamination, and other factors on the ingot growth process. The crucible is located within the furnace and defines a holding space for the raw materials used for ingot growth. By adjusting parameters such as the crucible's position, rotational speed, and lifting speed, the temperature gradient, melt, and other conditions during ingot growth can be controlled, thereby affecting the quality of the ingot. The heater is located within the furnace and used to heat the crucible. It is the primary heat source during ingot growth, heating the raw materials in the crucible to a molten state and providing the necessary conditions for ingot growth. The control device is the control device for the ingot growth apparatus according to the above-described embodiment of the present invention. The power adjustment mechanism is used to adjust the heater's power. A measuring mechanism monitors parameters such as the actual ingot diameter in real time and transmits the data to a data processing mechanism for analysis and processing, facilitating precise control of the ingot growth process. These mechanisms, each playing an important role in the ingot growth apparatus, collectively achieve precise control and optimization of the ingot growth process.

[0113] In the description of this specification, reference to the terms "one embodiment," "another embodiment," etc., means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent.

[0114] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for growing a single crystal, characterized in that: include: In the isodiameter growth stage, the initial function between the actual diameter of the crystal rod and time t is recorded as D = F0(t), F0(t) = A0*sin(ω0*t+Φ)+d, or F0(t) = A0*cos(ω0*t+Φ)+d, where d is the target diameter of the crystal rod, A0 is the initial amplitude, ω0 is the initial angular frequency, and Φ is the initial phase; When F0(t) meets the preset conditions, the pulling rate of the crystal is locked, and the initial function is piecewise corrected using the measurement results of the actual diameter of the crystal rod at the subsequent n different measurement moments to obtain the corrected piecewise function D=F h (t), F h (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, D=F h (t) includes multiple sub-functions: The function between the actual diameter of the crystal rod at time t0 and time t is the initial function D = F0(t); Function D=F1(t) between the actual diameter of the crystal rod after calibration at time t1 and time t; and t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z The time is the zth measurement time after the preset condition is met, where z is a positive integer and 2≤z≤n; Calculate F′ at the corresponding moment h (t), if F′ h (t) / (A h *ω h )≥ set value x, then increase the heating power and the increase is ΔP1; if F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥ set value x, then reduce the heating power and the reduction amount is ΔP2, where A h 、ω h t h The amplitude and angular frequency at the moment, set value x>0, Among them, in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the parameter corresponding to the former measurement, and the other is obtained by calculation to achieve a correction; ΔP1=m1*|F′ h (t) / (A h *ω h )|, ΔP2=m2*|F′ h (t) / (A h *ω h )|, m1 and m2 are temperature control coefficients, 0 <m1≤15、0<m2≤15; F′ h (t) / (A h *ω h )<set value x, If F h (t)>d, and F′ h (t)>0, increase the actual liquid port distance; if F h (t)>d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)>0, increase the actual liquid port distance.

2. The method for growing a single crystal according to claim 1, wherein: The step of sequentially correcting the initial function by segment by segment using the measurement results of the actual diameter of the crystal ingot at n different subsequent measurement moments includes: When F0(t) meets the preset conditions, the actual diameter D1 of the crystal rod at time t1 is measured for the first time. The corresponding parameter A1 is equal to the initial corresponding parameter A0, and ω1 is obtained by calculation to achieve a correction; or, The corresponding parameter ω1 is equal to the initial corresponding parameter ω0, and A1 is obtained by calculation to achieve a correction.

3. The method for growing a single crystal according to claim 1, wherein: In the p consecutive calibrations, at least one calibration is performed to calculate the parameter A, and at least one calibration is performed to calculate the parameter ω, where p is a positive integer and p≥2.

4. The method for growing a single crystal according to claim 3, wherein: In any two adjacent calibrations, one calibration is performed to calculate the parameter A, and the other calibration is performed to calculate the parameter ω.

5. The method for growing a single crystal according to claim 1, wherein: The constant diameter growth stage includes multiple sub-stages that proceed in sequence over time. The set values ​​x corresponding to the multiple sub-stages are different, and the set values ​​x of the multiple sub-stages decrease in chronological order.

6. The method for growing a single crystal according to claim 5, wherein: The current equal diameter length of the crystal ingot is L, the target equal diameter length of the crystal ingot is L', and the following conditions are satisfied: When 100mm≤L<300mm, x=x1, When 300mm≤L<L'-500mm, x=x2, When L'-500mm≤L≤L', x=x3, 0.01≤x3≤1 / 2, where L'≥1300mm.

7. The method for growing a single crystal according to claim 6, wherein: When 300mm≤L<L' / 2, When L' / 2≤L<L'-500mm, 8. The method for growing a single crystal according to claim 1, wherein: When F0(t)=A0*sin(ω0*t+Φ)+d, the preset condition is F0(t)=d, and F′0(t)>0; When F0(t)=A0*cos(ω0*t+Φ)+d, the preset condition is F0(t)=d+A0.

9. The method for growing a single crystal according to claim 1, wherein: When F0(t) meets the preset conditions, a measurement is performed every preset time, which is less than 1 minute.

10. The method for growing a single crystal according to claim 1, wherein: Change the heating power through the top heater on the upper side of the crucible, m1≤1, m2≤1; or, Change the heating power by the side heater on the periphery of the crucible, 1≤m1≤5, 1≤m2≤5; or, The heating power is changed by the bottom heater on the lower side of the crucible, 5≤m1≤15, 5≤m2≤15.

11. The method for growing a single crystal according to claim 1, wherein: The change in the crucible rising rate is Δv, Δv=|k*ΔD / Δt|, ΔD is the difference in the diameter of the crystal rod between two adjacent measurement moments, and Δt is the time interval between two adjacent measurement moments, where 0.1≤k≤2.

12. The method for growing a single crystal according to claim 1, wherein: The actual liquid port distance takes the target liquid port distance as the zero point and fluctuates within the range of -5 mm to 5 mm.

13. A control device for a single crystal growth device, characterized in that: include: A measuring mechanism, the measuring mechanism is used to measure the actual diameter D of the crystal ingot; a data processing mechanism, the data processing mechanism communicating with the measuring mechanism and used to simulate an initial function D=F0(t) between the actual diameter of the crystal ingot and time t, F0(t)=A0*sin(ω0*t+Φ)+d, or F0(t)=A0*cos(ω0*t+Φ)+d, where d is the target diameter of the crystal ingot, A0 is the initial amplitude, ω0 is the initial angular frequency, and Φ is the initial phase; The judging mechanism is used to judge whether F0(t) meets the preset conditions. When F0(t) meets the preset conditions, the pulling rate of the crystal is locked, and the initial function is segmentedly corrected using the measurement results of the actual diameter of the crystal rod at the subsequent n different measurement moments to obtain the corrected segmented function D=F h (t), F h (t) = A h *sin(ω h *t+Φ)+d, or, F h (t) = A h *cos(ω h *t+Φ)+d, where A h is the corrected amplitude, ω h is the corrected angular frequency, D=F h (t) includes multiple sub-functions: the function between the actual diameter of the crystal rod at time t0 and time t is the initial function D=F0(t); the function between the actual diameter of the crystal rod after calibration at time t1 and time t is D=F1(t); and, t z The function D=F between the actual diameter of the crystal rod after calibration and time t z (t), F z (t) = A z *sin(ω z *t+Φ)+d, or, F z (t) = A z *cos(ω z *t+Φ)+d,t z The time is the zth measurement time after the preset condition is satisfied, where z is a positive integer and 2≤z≤n, and the data processing mechanism is configured to: in two adjacent measurements, one of the parameters A and ω corresponding to the latter measurement is equal to the parameter corresponding to the former measurement, and the other is obtained by calculation to achieve a correction; The power regulating mechanism is used to adjust the heating power, and the judging mechanism is also used to judge F' h (t) / (A h *ω h ) and the set value x, if F′ h (t) / (A h *ω h )≥ set value x, the power regulating mechanism increases the heating power and the increase is ΔP1. If F′ h (t) / (A h *ω h )<0 and |F′ h (t) / (A h *ω h )|≥ set value x, the power adjustment mechanism reduces the heating power and the reduction amount is ΔP2; ΔP1=m1*|F′ h (t) / (A h *ω h )|, ΔP2=m2*|F′ h (t) / (A h *ω h )|, m1 and m2 are both temperature control coefficients, 0 <m1≤15、0<m2≤15; F′ h (t) / (A h *ω h )<set value x, If F h (t)>d, and F′ h (t)>0, increase the actual liquid port distance; if F h (t)>d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)<0, reduce the actual liquid port distance; if F h (t)<d, and F′ h (t)>0, increase the actual liquid port distance.

14. A single crystal growth device, characterized in that: include: A furnace body and a crucible, wherein the crucible is arranged in the furnace body and defines a containing space; a heater, the heater being disposed in the furnace body and being used to heat the crucible; The control device is the control device of the single crystal growth equipment according to claim 13, and the power adjustment mechanism is used to adjust the power of the heater.

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