Control method of crystal furnace integrated with catcher

Abstract

The invention provides a control method of a crystal furnace integrated with a catcher, and relates to the technical field of crystal furnace control, and the control method comprises the following steps: according to a plurality of surface thermal images, judging whether floating objects exist on the surface of a melt or not; if yes, whether the floating position of the floating object changes or not is judged, if the floating position does not change, the target height and the target area are obtained, the current position of the catcher body is obtained, first target vertical displacement is obtained according to the current position and the target height, and the target rotation angle is obtained according to the current position and the target area; after the trapper body is controlled to rotate around the first rotating shaft by the target rotating angle, the trapper body is controlled to move downwards by the first target vertical displacement, the crystal furnace can flexibly adjust the position and the angle of the trapper to adapt to different crystal growth conditions and floating object distribution conditions, and therefore the floating object trapping efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of crystal furnace control, and in particular to a control method for a crystal furnace with an integrated catcher. Background Art

[0002] With the continuous development of crystal growth technology, the requirements for crystal quality are getting higher and higher. During the crystal growth process, floating objects in the melt will seriously affect the quality and performance of the crystal.

[0003] In existing crystal growth equipment, the rotation of the crucible is usually to promote the uniformity and convection of the melt, but this rotation may also cause the distribution of floating objects on the melt surface to be more complicated, increasing the difficulty of removing the floating objects. Traditional crystal furnaces usually do not have special devices to remove floating objects on the melt surface, which makes the crystal growth process susceptible to interference from impurities, resulting in more defects in the grown crystals and reduced performance. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present invention aims to provide a control method for a crystal furnace with an integrated catcher to remove floating objects on the surface of the melt.

[0005] The control method is implemented based on a crystal furnace with an integrated catcher, and the crystal furnace comprises: A furnace body, wherein a hollow cavity is provided in the furnace body, a crucible for accommodating a melt is provided in the hollow cavity, the crucible rotates about a first rotation axis extending in a height direction of the furnace body, and a furnace top plate is provided on the top of the furnace body; A seed crystal rod, the seed crystal rod is vertically arranged on the top plate of the furnace body, the seed crystal rod at least comprises a crystal growth platform for placing seed crystals, and the crystal growth platform moves in the hollow cavity along the height direction of the furnace body; A capture assembly, the capture assembly is arranged on the top plate of the furnace body and sleeved outside the seed rod, the capture assembly at least comprises a capturer body and a driving assembly, the driving assembly is used to drive the capturer body to rotate around the first rotation axis and / or move along the height direction of the furnace body; The control method comprises the following steps: Acquire in real time a plurality of surface thermal images of the melt surface of the melt within a first preset time period, and determine whether there are floating objects on the melt surface according to the plurality of surface thermal images; If the melt surface has the floating object, determine whether the floating position of the floating object changes; if the floating position does not change, obtain a target height and a target area, wherein the target height is the height of the melt surface from the bottom of the hollow cavity; and the target area is the area on the melt surface with the floating object; Acquire the current position of the trap body, obtain the first target vertical displacement according to the current position and the target height, and obtain the target rotation angle according to the current position and the target area; After controlling the capture device body to rotate about the first rotation axis to the target rotation angle, controlling the capture device body to move downward by the first target vertical displacement, and controlling the capture device body to capture the floating object.

[0006] According to the technical solution provided by the present invention, the driving component at least includes: A first annular chute, the first annular chute is arranged on the top plate of the furnace body, and the first annular chute is arranged concentrically with the first rotating shaft; a first sliding block, wherein the first sliding block is slidably connected to the first annular sliding groove, and the first sliding block is connected to the catcher body at a side away from the first annular sliding groove; A first driving motor is used to drive the first sliding block to slide, so that the catcher body rotates around the first rotating axis.

[0007] According to the technical solution provided by the present invention, the melt surface includes a plurality of adjacent and concentrically distributed radial surface areas; the first sliding block is connected to a lifting mechanism on the side away from the first annular slide groove, and the lifting mechanism is connected to the catcher body on the side away from the first sliding block, and the catcher body extends radially along the crucible, and the radial extension length is the difference between the radius of the accommodating space in the crucible and the radius of the crystal growth platform, and the lifting mechanism is used to lift the catcher body along the height direction of the furnace body.

[0008] According to the technical solution provided by the present invention, a thermal imager is provided on the top plate of the furnace body, and the thermal imager is used to take surface thermal images of the melt surface; a capture cavity is provided in the catcher body, and a plurality of capture holes are evenly distributed along its extension direction on the catcher body, and each of the capture holes is connected to the capture cavity, and the capture cavity of the catcher body is connected to the catcher vacuum pump through a first connecting pipe; each of the capture holes is equipped with a corresponding first switch, and the first switch has an initial state and an on state. In the on state, the first switch opens the corresponding capture hole to capture floating objects, and in the initial state, the first switch closes the corresponding capture hole.

[0009] According to the technical solution provided by the present invention, after determining whether the floating position of the floating object has changed, the following steps are also included: If the floating position changes, position change information is obtained based on a plurality of surface thermal images, and the position change information at least includes the moving speed of the floating object and the predicted moving path; According to the position change information, a control parameter is obtained, and the control parameter at least includes a target sliding speed and a target sliding direction, the target sliding speed is the sliding speed of the first sliding block in the first annular sliding groove; the target sliding direction includes the first sliding block sliding clockwise or counterclockwise; Obtain a second target vertical displacement, control the capturer body to move down by the second target vertical displacement, start the capturer vacuum pump, and control the first sliding block to move under the control parameters so that the capturer body continuously rotates around the first rotation axis; the second target vertical displacement is less than the first target vertical displacement.

[0010] According to the technical solution provided by the present invention, the control of the catcher body to catch floating objects specifically includes the following steps: Acquire the region length of the target region, where the region length is the radial length of the target region along the melt surface; When the area length is less than the radial extension length, a target capture hole is obtained according to the area length, and the target capture hole is a capture hole in the area on the capturer body corresponding to the target area; The first switch corresponding to the target capturing hole is controlled to switch from the initial state to the on state, and the first switches in the capturing holes other than the target capturing hole maintain the initial state unchanged.

[0011] According to the technical solution provided by the present invention, after determining whether there are floating objects on the surface of the melt, the following steps are also included: If there is no floating matter on the melt surface, the temperature uniformity of the melt surface is obtained according to the surface thermal imaging; If the temperature uniformity is less than the target uniformity, obtaining the crucible rotation direction and the crucible rotation speed of the crucible; If the crucible rotation speed is greater than or equal to a first preset speed, obtaining a coordination parameter according to a uniformity deviation between the temperature uniformity and the target uniformity, the coordination parameter comprising at least a third target vertical displacement and a coordinated sliding speed corresponding to the third target vertical displacement; Control all the first switches to keep the initial state unchanged or turn off the capturer vacuum pump, and when the capturer body moves down the third target vertical displacement, control the first sliding block to slide in the same direction as the crucible rotation direction at the coordinated sliding speed, so that the capturer body continues to rotate around the first rotation axis.

[0012] According to the technical solution provided by the present invention, after controlling the first sliding block to slide in the same direction as the rotation direction of the crucible at the coordinated sliding speed, the following steps are also included: When the trap body rotates continuously around the first rotation axis for a second preset time period, the surface thermal image at the end of the second preset time period is obtained, thereby obtaining real-time temperature uniformity; If the real-time temperature uniformity is less than the target uniformity, the first sliding block is controlled to slide in a direction opposite to the rotation direction of the crucible.

[0013] According to the technical solution provided by the present invention, controlling the first sliding block to slide in a direction opposite to the rotation direction of the crucible specifically comprises the following steps: According to the real-time temperature uniformity, a pulling height and an updated coordinated sliding speed corresponding to the pulling height are obtained, wherein the pulling height is a height of the catcher body rising toward the side close to the furnace top plate; After the catcher body is controlled to rise to the pulling height, the first sliding block slides at the updated coordinated sliding speed in a direction opposite to the rotation direction of the crucible.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the setting of the capture assembly in the present invention can effectively remove floating objects on the surface of the melt and improve the quality of crystal growth. The capturer body can rotate around the first rotation axis and / or move along the height direction of the furnace body, and can flexibly adjust the position and angle to adapt to different crystal growth conditions and floating object distribution conditions, thereby improving the capture efficiency of floating objects. The capture assembly is arranged on the top plate of the furnace body and sleeved on the seed crystal rod, so that the seed crystal rod and the floating object removal device can work together. During the crystal growth process, the movement of the seed crystal rod and the rotation and movement of the capturer body can cooperate with each other to improve the efficiency of crystal growth; the control method is based on the crystal furnace to monitor whether there are floating objects on the melt surface in real time, and to capture the floating objects in a targeted manner, which can effectively prevent these floating objects from mixing into the growing crystal and avoid them from becoming impurities in the crystal, making the crystal growth process more stable and controllable, thereby improving the purity and internal structure quality of the crystal. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A cross-sectional schematic diagram of a crystal furnace with an integrated catcher provided by the present invention; Figure 2 A schematic diagram of the top view of the crystal furnace with integrated catcher provided by the present invention; Figure 3 A schematic diagram of the structure of the trap body provided by the present invention; Figure 4A flow chart of the steps of the control method of the crystal furnace with integrated catcher provided by the present invention.

[0016] The text annotations in the figure represent: 1. furnace body; 2. seed crystal rod; 3. crystal growth platform; 41. first annular slide groove; 42. first sliding block; 43. lifting mechanism; 44. catcher body; 441. catch hole; 45. first connecting pipe; 5. crucible. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0018] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] Example 1 As mentioned in the background technology, in order to solve the problems in the prior art, the present invention proposes a crystal furnace with integrated catcher, please refer to Figure 1 As shown, the crystal furnace comprises: A furnace body 1, wherein a hollow cavity is provided in the furnace body 1, wherein a crucible 5 for accommodating a melt is provided in the hollow cavity, wherein the crucible 5 rotates about a first rotation axis extending in a height direction of the furnace body 1, and wherein a furnace top plate is provided on the top of the furnace body 1; Specifically, a turntable is provided at the bottom of the hollow cavity, and the turntable is connected to a motor for driving the turntable to rotate. The crucible 5 is fixedly provided on the turntable. The crucible 5 is generally in the shape of a hollow truncated cone with a circular first opening on the top. The crucible 5 contains a melt of a certain height, and the top surface of the melt is circular. The first rotating axis is the central axis of the turntable.

[0020] A seed crystal rod 2, wherein the seed crystal rod 2 is vertically arranged on the top plate of the furnace body, and the seed crystal rod 2 at least comprises a crystal growth platform 3 for placing seed crystals, and the crystal growth platform 3 can move in the hollow cavity along the height direction of the furnace body 1; Optionally, the crystal growth platform 3 is a cylinder, and the seed crystal rod 2, the crystal growth platform 3, and the crucible 5 are concentrically arranged.

[0021] A capture assembly is arranged on the top plate of the furnace body and is sleeved outside the seed rod 2. The capture assembly at least includes a capturer body 44 and a driving assembly. The driving assembly is used to drive the capturer body 44 to rotate around the first rotation axis and / or move along the height direction of the furnace body 1.

[0022] Exemplarily, when the crucible 5 rotates and causes floating objects to move on the melt surface, the catcher body 44 can track the floating objects by rotating and moving, ensuring that they can be captured in a timely and effective manner, thereby reducing the interference of the floating objects on the crystal growth.

[0023] Furthermore, the driving assembly at least comprises: A first annular chute 41, wherein the first annular chute 41 is disposed on the top plate of the furnace body, and the first annular chute 41 is disposed concentrically with the first rotating shaft; Please refer to Figure 2 As shown, specifically, the crucible 5 is cylindrical, and the accommodating space therein for accommodating the melt is also cylindrical; A first sliding block 42, wherein the first sliding block 42 is slidably connected to the first annular sliding groove 41, and the catcher body 44 is connected to the side of the first sliding block 42 away from the first annular sliding groove 41; Specifically, the first sliding block 42 is disposed in the middle of the catcher body 44, and the radius of the first annular chute 41 may be the difference between the radius length of the accommodating space of the crucible 5 and half the length of the catcher body 44. The first sliding block 42 is in the shape of an arc block, and the arc is completely adapted to the arc of the first annular chute 41, so that the first sliding block 42 can slide along the trend of the first annular chute 41.

[0024] A first driving motor, wherein the first driving motor is used to drive the first sliding block 42 to slide, so that the catcher body 44 rotates around the first rotation axis.

[0025] Specifically, the first driving motor is arranged at the center of the furnace top plate (the first annular chute 41 is away from the furnace body 1 side), the output shaft of the motor is directly connected to the horizontally arranged rotating rod, so that the rotational motion of the motor can be effectively transmitted to the rotating rod, and a connecting rod is vertically connected to the end of the rotating rod away from the motor output shaft, one end of the connecting rod is vertically connected to the rotating rod, and the other end is connected to the first sliding block 42. The length and connection method of the connecting rod should ensure that the circular motion of the rotating rod can be converted into the sliding motion of the first sliding block 42 in the first annular chute 41. When the first driving motor is running, the output shaft of the motor starts to rotate, driving the rotating rod connected thereto to make a circular motion around the output shaft of the motor. Since the connecting rod is perpendicular to the rotating rod and one end is connected to the rotating rod, the circular motion of the rotating rod is transmitted to the first sliding block 42 through the connecting rod. Because the first sliding block 42 is constrained by the first annular chute 41 and can only move along the track of the chute, the first sliding block 42 slides in the first annular chute 41 under the push of the connecting rod. This sliding motion causes the catcher body 44 connected to the first sliding block 42 to rotate around the first rotation axis, so that floating objects on the surface of the melt in the crucible 5 that move due to the rotation of the crucible 5 can be tracked as needed.

[0026] Furthermore, the melt surface includes a plurality of adjacent and concentrically distributed radial surface areas; the radial surface area is approximately fan-shaped, and the first sliding block 42 is connected to a lifting mechanism 43 on the side away from the first annular slide groove 41, and the lifting mechanism 43 is connected to the catcher body 44 on the side away from the first sliding block 42, and the catcher body 44 extends radially along the crucible 5, and the radial extension length is the difference between the radius of the accommodating space in the crucible 5 and the radius length of the crystal growth platform 3, so as to ensure that no matter where the first sliding block 42 is in the first annular slide groove 41, the catcher body 44 can cover the corresponding area of ​​the melt surface, thereby covering all melt surfaces, and the lifting mechanism 43 is used to lift the catcher body 44 along the height direction of the furnace body 1.

[0027] Optionally, the lifting mechanism 43 is a hydraulic cylinder, the fixed end of which is fixedly connected to the first sliding block 42 , and the free end of which can move along the height direction of the furnace body 1 , and the free end is connected to the center position of the catcher body 44 .

[0028] For further information, please refer to Figure 3 As shown, the capturer body 44 can be a long strip, or a long strip with arc-shaped ends. Among the arcs at both ends, the curvature of the arc at the inner end is adapted to the curvature of the crystal growth platform 3, and the curvature of the arc at the outer end is adapted to the curvature of the inner wall of the crucible 5, and the free end is connected to the midpoint of the long strip.

[0029] The crystal furnace proposed in this embodiment is equipped with a capture assembly, and the capturer body 44 can not only move up and down, but also rotate above the melt surface (very close to the melt surface but not touching it), so that floating objects can be tracked by the rotation of the capturer body 44 and thus captured. Moreover, since the capturer body 44 is in the shape of an elongated strip, and the extended length of the elongated strip is exactly equal to the difference between the radius length of the accommodating space of the crucible 5 and the radius length of the crystal growth platform 3, it can be ensured that the capturer body 44 rotates one circle to cover the entire melt surface, making it more likely that floating objects at any position will be captured.

[0030] In a preferred embodiment, a thermal imager is provided on the top plate of the furnace body, and the thermal imager is used to take surface thermal images of the melt surface; a capture cavity is provided in the catcher body 44, and a plurality of capture holes 441 are evenly distributed along its extension direction on the catcher body 44, and each of the capture holes 441 is connected to the capture cavity, and the capture cavity of the catcher body 44 is connected to the catcher vacuum pump through a first connecting pipe 45; each of the capture holes 441 is equipped with a corresponding first switch, and the first switch has an initial state and an open state. In the open state, the first switch opens the corresponding capture hole to capture floating objects, and in the initial state, the first switch closes the corresponding capture hole.

[0031] Specifically, a traditional crystal furnace is provided with an observation window on the side wall of the furnace body 1, through which the staff can observe the actual growth situation inside the hollow cavity, and then observe the floating objects on the surface of the melt in the crucible 5. However, this method is relatively subjective and requires continuous tracking by personnel. In this embodiment, a thermal imager is used to take thermal images of the melt surface. By analyzing the thermal images, it can be determined whether there are floating objects on the melt surface.

[0032] Specifically, the number of capture holes 441 on the capturer body 44 is designed according to the extension length of the capturer body 44, and can be set in one row or multiple rows, depending on the width of the capturer body 44. When the width of the capturer body 44 is small, one row of capture holes 441 is sufficient; when the width of the capturer body 44 is small, multiple rows of capture holes 441 can be set, or the size of the capture holes 441 can be adjusted to be larger, so as to improve the capture success rate and capture efficiency.

[0033] Furthermore, the catcher body 44 is a roughly rectangular structure with a cavity, and the cavity is the capture cavity. Therefore, a capture hole 441 can also be set on the side of its rectangular structure. When the catcher body 44 also has a capture hole 441 on the side close to the crystal growth platform 3 along the radial direction of the melt surface, floating objects on the crystal growth platform 3 can also be captured. When floating objects are found near the center of the melt surface, the side capture hole 441 can be opened for capture.

[0034] Specifically, the first switch may be a ball valve or a butterfly valve, the open state is a valve open state, and the initial state is a valve closed state.

[0035] In this embodiment, a plurality of capture holes 441 are provided on the capturer body 44, and a valve for independently controlling the opening and closing of each capture hole 441 is installed, so as to achieve the technical effect of local capture, so that the capture holes 441 in the area of ​​the capturer body 44 corresponding to the melt surface without floating objects can be closed in time, so that negative pressure exists above the melt surface with floating objects, and the negative pressure is eliminated above the melt surface without floating objects, thereby ensuring that the state of the airflow above the melt surface without floating objects is not affected, and further ensuring that the surrounding environment of the crystal growth is not damaged as much as possible while capturing the floating objects, thereby improving the quality of the crystal growth.

[0036] Example 2 On the basis of Example 1, this example proposes a control method for a crystal furnace with an integrated catcher, which is used to control the crystal furnace with an integrated catcher as described in Example 1. Figure 4 As shown, the control method comprises the following steps: S1. Acquire in real time a plurality of surface thermal images of the melt surface of the melt within a first preset time period, and determine whether there are floating objects on the melt surface according to the plurality of surface thermal images; Specifically, a reference temperature distribution is established, and the thermal imaging of the melt surface is analyzed in the absence of floating objects to establish a reference temperature distribution model. This model may include characteristics such as the average temperature of the melt surface, the temperature variation range, and the temperature gradient. Exemplarily, by repeatedly measuring the thermal imaging of the melt surface without floating objects under different conditions, it is determined that the typical temperature range of the melt surface is [X, Y] degrees Celsius, the average temperature is Z degrees Celsius, and the temperature gradient fluctuates within a certain range. When the surface thermal imaging within the first preset time length is obtained, it is compared with the reference temperature distribution. If an obvious temperature abnormality area is found in the thermal imaging, it indicates that there are floating objects on the melt surface.

[0037] For example, if the temperature of a certain area is found to be significantly higher or lower than the reference temperature range in the surface thermal imaging, or the temperature gradient has changed significantly, then there are floating objects in this area. The principle is that the presence of floating objects will change the heat conduction and heat dissipation of the melt surface, thereby causing changes in temperature distribution.

[0038] S2. If there is the floating object on the surface of the melt, determine whether the floating position of the floating object changes. If the floating position does not change, obtain a target height and a target area, wherein the target height is the height of the melt surface from the bottom of the hollow cavity; and the target area is the area on the melt surface where the floating object exists. Specifically, when the tension on the melt surface is stable, the airflow in the hollow cavity is stable, there are no other influencing factors, and the crucible 5 does not rotate, the position of the floating objects floating on the melt surface will not change. At this time, it is only necessary to determine the position of the floating objects and move the catcher body 44 down to a position close to the melt surface to capture the floating objects. At this time, the catcher body 44 will no longer move after reaching the target position.

[0039] Specifically, when the positions of the regions in several of the surface thermal images that are obviously higher or lower than the reference temperature range, or where the temperature gradient has changed significantly, do not change, it indicates that the floating position has not changed.

[0040] S3, obtaining the current position of the capture device body 44, obtaining the first target vertical displacement according to the current position and the target height, and obtaining the target rotation angle according to the current position and the target area; Optionally, the catcher body 44 can be in an initial position, that is, closest to the furnace top plate side, or in any position between the initial position and the lowest falling position, and the lowest falling position is the critical height of contacting the melt surface.

[0041] Furthermore, the interval distance between the catcher body 44 and the melt surface is obtained by model training. The interval distance can be understood as the distance between the catcher body 44 and the melt surface that does not affect the airflow on the melt surface and can achieve a good capture effect. The input of the model is the distance between the catcher body 44 and the melt surface, and the output is the capture success rate of the catcher body 44 for floating objects on the melt surface. The input corresponding to the output with the highest capture success rate is selected as the target distance.

[0042] Specifically, the current position is the height of the trap body 44 from the bottom of the hollow cavity. The sum of the target distance and the target height is calculated first, and the difference between the current position and the sum of the target distance and the target height is used as the first target vertical displacement.

[0043] The line connecting the projection midpoint of the catcher body 44 on the melt surface and the midpoint of the melt surface is taken as the first ray, and the line connecting the midpoint of the floating object and the midpoint of the melt surface is taken as the second ray. The angle between the first ray and the second ray is the target rotation angle.

[0044] Furthermore, the target rotation angle is the angle of the center angle of the area where the first sliding block 42 slides along the first annular sliding groove 41 , so the sliding distance of the first sliding block 42 in the first annular sliding groove 41 can be obtained.

[0045] S4. After controlling the trap body 44 to rotate around the first rotation axis to the target rotation angle, controlling the trap body 44 to move downward by the first target vertical displacement, and controlling the trap body 44 to capture floating objects, specifically, turning on the trap vacuum pump.

[0046] Specifically, by controlling the sliding distance of the first sliding block 42 in the first annular groove 41, the catcher body 44 is rotated around the first rotation axis to the target rotation angle. After rotating the target rotation angle, the projection of the catcher body 44 on the melt surface has an overlapping area with the floating object. Then, the catcher body 44 is moved down by the first target vertical displacement to reach a position close to the melt surface. At this time, the catcher vacuum pump is turned on to create a negative pressure on the melt surface, so that the floating objects floating on the melt surface are sucked into the capture cavity.

[0047] It should be noted that the implementation of this control method requires that all components be electrically connected to the control module of the crystal furnace itself, so that the control of the capture component is coordinated with the control of the crystal furnace itself.

[0048] In a preferred embodiment, after determining whether the floating position of the floating object has changed, the method further includes the following steps: If the floating position changes, position change information is obtained based on a plurality of surface thermal images, and the position change information at least includes a moving speed of the floating object and a predicted moving path; Specifically, when the temperature in a plurality of the surface thermal images is obviously higher or lower than the reference temperature range, or the position of the region where the temperature gradient has changed significantly has changed, it indicates that the floating position has changed.

[0049] Specifically, the position of the floating object is analyzed in time series according to the shooting time sequence of the thermal imaging. The position change of the floating object in two adjacent surface thermal imaging images is determined; the moving speed of the floating object is calculated based on the position change and the time interval. The Euclidean distance formula can be used to calculate the distance of the position change, and then divided by the time interval to obtain the speed value.

[0050] Specifically, the position data of floating objects at multiple consecutive time points are analyzed to understand their movement trends. By observing the position changes of floating objects over a period of time, the general direction and speed change pattern of their movement can be determined.

[0051] For example, by analyzing the positions of floating objects in the past N surface thermal images, it is found that the floating objects have been moving in a certain direction and the speed tends to gradually increase.

[0052] Based on the results of historical data analysis, a model of the movement of floating objects is established. Simple linear models or more complex nonlinear models can be used to predict the future position of floating objects.

[0053] For example, if the movement trend of the floating object is relatively linear, a linear regression model can be used to predict its future position. Assume that the movement speed of the floating object on the X-axis and Y-axis is and , the current location is , the predicted position after time t is .

[0054] Furthermore, as new surface thermal images are continuously acquired, the position information of floating objects is updated in real time, and the prediction model is dynamically adjusted and corrected. If it is found that the actual movement of floating objects deviates greatly from the prediction results, the model parameters are adjusted in time to improve the accuracy of the prediction.

[0055] For example, if new thermal imaging images show that the direction of movement of a floating object has changed, its position data is reanalyzed and the motion model is adjusted to better predict its future path.

[0056] According to the position change information, a control parameter is obtained, and the control parameter at least includes a target sliding speed and a target sliding direction, the target sliding speed is the sliding speed of the first sliding block 42 in the first annular sliding groove 41; the target sliding direction includes the first sliding block 42 sliding clockwise or counterclockwise; Specifically, the control parameters are generated according to the position change information of the floating object. The target sliding speed determines the movement speed of the first sliding block 42 in the first annular chute 41, and this speed needs to match the movement speed of the floating object so that the catcher body 44 can keep up with the movement of the floating object. The target sliding direction (clockwise or counterclockwise) is determined according to the movement direction of the floating object to ensure that the catcher body 44 can rotate in the direction of the floating object.

[0057] For example, if the floating object moves in a certain direction at a certain speed, the control parameters will cause the first sliding block 42 to slide in the annular groove at a corresponding speed, driving the capturer body 44 to rotate around the first rotation axis at a suitable speed and direction to track and capture the floating object.

[0058] Obtain a second target vertical displacement, control the capturer body 44 to move down by the second target vertical displacement, start the capturer vacuum pump, and control the first sliding block 42 to move under the control parameters so that the capturer body 44 continuously rotates around the first rotation axis; the second target vertical displacement is less than the first target vertical displacement.

[0059] Specifically, considering that when capturing a moving floating object, if the distance between the capture device body 44 and the melt surface is too close, the predicted moving path of the floating object may be affected during the rotation capture process, causing it to not move according to the predicted moving path, which may result in capture errors. Therefore, when capturing a moving floating object, the displacement of the capture device body 44 that controls the downward movement (the second target vertical displacement) is smaller than the displacement of the capture device body 44 that controls the downward movement when capturing a fixed floating object (the first target vertical displacement).

[0060] This embodiment is suitable for the situation where the position of the floating object changes. When the position of the floating object changes, the catcher body 44 can continue to rotate around the first rotation axis to fully cover the entire melt surface. In this way, no matter where the floating object moves, it is possible to be captured during the rotation of the catcher body 44. This dynamic capture method greatly improves the success rate of capturing moving floating objects.

[0061] In a preferred embodiment, the controlling the catcher body 44 to catch floating objects specifically includes the following steps: Acquire the region length of the target region, where the region length is the radial length of the target region along the melt surface; When the area length is less than the extension length, a target capture hole is obtained according to the area length, and the target capture hole is a capture hole 441 in the area corresponding to the target area on the capturer body 44; The first switch corresponding to the target capturing hole is controlled to switch from the initial state to the on state, and the first switches in the capturing holes 441 other than the target capturing hole maintain the initial state unchanged.

[0062] This embodiment takes into account that when the area with floating objects is small, it is not necessary to open the first switches in all the capturing holes 441. The capturing holes 441 corresponding to the area with floating objects are opened, and the capturing holes 441 corresponding to the area without floating objects are closed. The negative pressure generated by the vacuum pump of the capturer can be concentrated on these target capturing holes, which makes the negative pressure intensity in the target area relatively larger and has a stronger attraction to floating objects, thereby improving the efficiency of capturing floating objects.

[0063] The embodiment proposes to set a first switch to control the opening and closing of each of the capture holes 441, so that the capture holes 441 in different areas can be selectively opened to capture floating objects on the surface of the melt in the corresponding area. For example, for a traditional capturer that can only be lifted up and down vertically, if there are floating objects in multiple places in the same radial surface area of ​​the melt surface, it is only possible to capture all the floating objects by moving down multiple times. However, when using the crystal furnace proposed in this application, after reaching the target height by moving down once, the capture holes 441 corresponding to multiple areas with floating objects are controlled to open, so that simultaneous capture can be achieved, which is extremely efficient.

[0064] In addition, closing the capture holes 441 corresponding to the areas without floaters can reduce the unnecessary interference of these holes on the melt surface. If all capture holes 441 are opened, it may cause excessive fluctuations on the melt surface and affect the stability of the crystal growth environment. Opening only the target capture holes can reduce this interference and provide more stable conditions for crystal growth. In the actual crystal growth process, the distribution of floaters may be uneven, and sometimes floaters exist only in local areas. This method of selectively opening the capture holes 441 can better adapt to this situation, allowing the system to adjust according to the specific distribution of floaters and improve the adaptability of the system.

[0065] In a preferred embodiment, after determining whether there are floating objects on the melt surface, the following steps are further included: If there is no floating matter on the melt surface, the temperature uniformity of the melt surface is obtained according to the surface thermal imaging; Specifically, when there is no floating matter on the melt surface, the catcher body 44 no longer needs to assume the function of catching the floating matter, but can contribute to other functions.

[0066] If the temperature uniformity is less than the target uniformity, the crucible rotation direction and the crucible rotation speed of the crucible 5 are obtained; Specifically, when the temperature uniformity is not high, it means that the rotation of the crucible 5 at this time does not mix the melt well, and the convection of the melt can be further promoted by rotating the catcher body 44 and the crucible 5 in the same direction. This coordinated rotation can make the heat distribution inside the melt more uniform and improve the temperature uniformity.

[0067] If the crucible rotation speed is greater than or equal to a first preset speed, obtaining a coordination parameter according to a uniformity deviation between the temperature uniformity and the target uniformity, the coordination parameter comprising at least a third target vertical displacement and a coordinated sliding speed corresponding to the third target vertical displacement; Specifically, the coordination parameters are obtained through a correlation model established in advance through experiments or simulations. The input of the correlation model is the uniformity deviation between the temperature uniformity and the target uniformity, and the output is the coordination parameters, wherein the third target vertical displacement is the distance that the catcher body 44 needs to move downward when there is no floating material on the melt surface and the crucible rotation speed is greater than or equal to the first preset speed, but the temperature uniformity is less than the target uniformity. In order to enable the catcher body 44 to better coordinate with the rotation of the crucible 5, the airflow state close to the melt surface is changed, thereby improving the temperature uniformity of the melt surface.

[0068] Specifically, all the first switches are controlled to maintain the initial state unchanged or the catcher vacuum pump is turned off, and when the catcher body 44 moves down the third target vertical displacement, the first sliding block 42 is controlled to slide in the same direction as the crucible rotation direction at the coordinated sliding speed, so that the catcher body 44 continues to rotate around the first rotation axis.

[0069] Specifically, during the crystal growth process, the state of the airflow above the melt has an important influence on the temperature distribution of the melt. When the temperature uniformity is less than the target uniformity, although the crucible 5 is rotating, the uniform distribution of heat on the surface of the melt is not well achieved. At this time, after the catcher body 44 moves down the third target vertical displacement, it continues to rotate around the first rotation axis at a coordinated sliding speed to stir the airflow above the melt. Because the heat exchange on the surface of the melt is closely related to the airflow above. By stirring the airflow and changing the flow pattern and velocity distribution of the airflow, the thermal convection and thermal radiation processes on the surface of the melt can be affected. For example, when the catcher body 44 rotates, the surrounding airflow will produce a vortex flow, prompting the hot air and cold air to mix better above the melt surface, and then transfer the heat more evenly to various areas on the melt surface, providing a more stable thermal environment for crystal growth.

[0070] In a preferred embodiment, after controlling the first sliding block 42 to slide in the same direction as the rotation direction of the crucible at the coordinated sliding speed, the following steps are further included: When the trap body 44 rotates continuously around the first rotation axis for a second preset time, the surface thermal image at the end of the second preset time is obtained, thereby obtaining the real-time temperature uniformity; If the real-time temperature uniformity is less than the target uniformity, the first sliding block 42 is controlled to slide in a direction opposite to the rotation direction of the crucible.

[0071] Specifically, when the real-time temperature uniformity is less than the target uniformity, the first sliding block 42 is controlled to slide in a direction opposite to the crucible rotation direction. This flexible adjustment of the rotation direction can try different convection modes to find a more effective way to improve temperature uniformity.

[0072] For example, if the temperature uniformity is not improved after rotating in the same direction for a period of time, then rotating in the opposite direction may break the original convection pattern and promote the redistribution of heat inside the melt, thereby improving the temperature uniformity.

[0073] In a preferred embodiment, controlling the first sliding block 42 to slide in a direction opposite to the rotation direction of the crucible specifically comprises the following steps: According to the real-time temperature uniformity, a pulling height and an updated coordinated sliding speed corresponding to the pulling height are obtained, wherein the pulling height is a height of the catcher body 44 rising toward the furnace top plate side; After the catcher body 44 is controlled to rise to the pulling height, the first sliding block 42 slides in a direction opposite to the rotation direction of the crucible at the updated coordinated sliding speed.

[0074] Specifically, the pull height and updated coordinated sliding speed are calculated based on the real-time temperature uniformity. These parameters are usually determined based on pre-set algorithms and empirical models, taking into account factors such as the degree of deviation in temperature uniformity, the requirements for crystal growth, and the characteristics of the equipment.

[0075] For example, when the real-time temperature uniformity is low, the system may calculate a larger pulling height and an appropriate updated coordinated sliding speed according to a certain formula to enhance the adjustment effect on the temperature uniformity.

[0076] Specifically, when the catcher body 44 and the crucible 5 rotate in the opposite direction, it is necessary to rotate in the same direction so that the catcher body 44 is not too close to the melt surface, and the rotation speed cannot be too high to reduce the disturbance to the melt and reduce the interference to the crystal growth process. This helps to maintain the stability of the crystal growth interface and reduce the generation of crystal defects.

[0077] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. The above is only a preferred implementation method of the present invention. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements, modifications or changes can be made, and the above technical features can be combined in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the protection scope of the present invention.

Claims

1. A control method for a crystal furnace with an integrated catcher, characterized in that: The control method is implemented based on a crystal furnace with an integrated catcher, and the crystal furnace comprises: A furnace body (1), wherein a hollow cavity is provided in the furnace body (1), a crucible (5) for accommodating a melt is provided in the hollow cavity, the crucible (5) rotates about a first rotation axis extending in a height direction of the furnace body (1), and the furnace body (1) has a furnace top plate on the top; A seed crystal rod (2), the seed crystal rod (2) being vertically arranged on the top plate of the furnace body, the seed crystal rod (2) comprising at least a crystal growth platform (3) for placing seed crystals, the crystal growth platform (3) moving in the hollow cavity along the height direction of the furnace body (1); a capture assembly, the capture assembly being arranged on the top plate of the furnace body and sleeved outside the seed crystal rod (2), the capture assembly comprising at least a capturer body (44) and a drive assembly, the drive assembly being used to drive the capturer body (44) to rotate around the first rotation axis and / or to move along the height direction of the furnace body (1); The control method comprises the following steps: Acquire in real time a plurality of surface thermal images of the melt surface of the melt within a first preset time period, and determine whether there are floating objects on the melt surface according to the plurality of surface thermal images; If the melt surface has the floating object, determine whether the floating position of the floating object changes; if the floating position does not change, obtain a target height and a target area, wherein the target height is the height of the melt surface from the bottom of the hollow cavity; and the target area is the area on the melt surface with the floating object; Acquiring the current position of the capture device body (44), obtaining a first target vertical displacement according to the current position and the target height, and obtaining a target rotation angle according to the current position and the target area; After controlling the capture device body (44) to rotate about the first rotation axis to the target rotation angle, the capture device body (44) is controlled to move downward by the first target vertical displacement, and the capture device body (44) is controlled to capture the floating object.

2. The control method of the crystal furnace with integrated catcher according to claim 1, characterized in that: The drive assembly at least comprises: A first annular chute (41), the first annular chute (41) being arranged on the top plate of the furnace body, and the first annular chute (41) being arranged concentrically with the first rotating shaft; a first sliding block (42), the first sliding block (42) being slidably connected in the first annular sliding groove (41), and the side of the first sliding block (42) away from the first annular sliding groove (41) being connected to the catcher body (44); A first driving motor, the first driving motor is used to drive the first sliding block (42) to slide, so that the catcher body (44) rotates around the first rotation axis.

3. The control method of the crystal furnace with integrated catcher according to claim 2, characterized in that: The melt surface comprises a plurality of adjacent and concentrically distributed radial surface areas; the first sliding block (42) is connected to a lifting assembly on the side away from the first annular slide groove (41), and the lifting assembly at least comprises a lifting mechanism (43) provided on the first sliding block (42); the lifting mechanism (43) is connected to the catcher body (44) on the side away from the first sliding block (42); the catcher body (44) extends radially along the crucible (5), and the radial extension length is the difference between the radius of the accommodating space in the crucible (5) and the radius of the crystal growth platform (3); the lifting mechanism (43) is used to lift the catcher body (44) along the height direction of the furnace body (1).

4. The control method of the crystal furnace with integrated catcher according to claim 3, characterized in that: A thermal imager is provided on the top plate of the furnace body, and the thermal imager is used to take thermal images of the surface; a capture cavity is provided in the capture body (44), and a plurality of capture holes (441) are evenly distributed along the extension direction of the capture body (44), each of the capture holes (441) is connected to the capture cavity, and the capture cavity of the capture body (44) is connected to the capture vacuum pump through a first connecting pipe (45); each of the capture holes (441) is equipped with a corresponding first switch, and the first switch has an initial state and an open state. In the open state, the first switch opens the corresponding capture hole to capture floating objects, and in the initial state, the first switch closes the corresponding capture hole.

5. The control method of the crystal furnace with integrated catcher according to claim 1, characterized in that: After determining whether the floating position of the floating object has changed, the following steps are also included: If the floating position changes, position change information is obtained based on a plurality of surface thermal images, and the position change information at least includes the moving speed of the floating object and the predicted moving path; According to the position change information, a control parameter is obtained, the control parameter at least comprising a target sliding speed and a target sliding direction, the target sliding speed being the sliding speed of the first sliding block (42) in the first annular sliding groove (41); the target sliding direction comprising the first sliding block (42) sliding clockwise or counterclockwise; After obtaining a second target vertical displacement, controlling the catcher body (44) to move downward by the second target vertical displacement, starting the catcher vacuum pump, and controlling the first sliding block (42) to move under the control parameters, so that the catcher body (44) continuously rotates around the first rotation axis; the second target vertical displacement is less than the first target vertical displacement.

6. The control method of the crystal furnace with integrated catcher according to claim 4, characterized in that: The method of controlling the catcher body (44) to catch floating objects specifically comprises the following steps: Acquire the region length of the target region, where the region length is the radial length of the target region along the melt surface; When the area length is less than the radial extension length, a target capture hole is obtained according to the area length, and the target capture hole is a capture hole (441) in an area on the capture device body (44) corresponding to the target area; The first switch corresponding to the target capture hole is controlled to switch from the initial state to the on state, and the first switches in the capture holes (441) other than the target capture hole maintain the initial state unchanged.

7. The control method of the crystal furnace with integrated catcher according to claim 4, characterized in that: After determining whether there are floating objects on the melt surface, the method further includes the following steps: If there is no floating matter on the melt surface, the temperature uniformity of the melt surface is obtained according to the surface thermal imaging; If the temperature uniformity is less than the target uniformity, obtaining the crucible rotation direction and crucible rotation speed of the crucible (5); If the crucible rotation speed is greater than or equal to a first preset speed, obtaining a coordination parameter according to a uniformity deviation between the temperature uniformity and the target uniformity, the coordination parameter comprising at least a third target vertical displacement and a coordinated sliding speed corresponding to the third target vertical displacement; All the first switches are controlled to maintain the initial state unchanged or the catcher vacuum pump is turned off, and when the catcher body (44) moves down the third target vertical displacement, the first sliding block (42) is controlled to slide in the same direction as the crucible rotation direction at the coordinated sliding speed, so that the catcher body (44) continues to rotate around the first rotation axis.

8. The control method of the crystal furnace with integrated catcher according to claim 7, characterized in that: After controlling the first sliding block (42) to slide in the same direction as the rotation direction of the crucible at the coordinated sliding speed, the following steps are also included: When the trap body (44) rotates continuously around the first rotation axis for a second preset time period, a thermal image of the surface at the end of the second preset time period is obtained, thereby obtaining real-time temperature uniformity; If the real-time temperature uniformity is less than the target uniformity, the first sliding block (42) is controlled to slide in a direction opposite to the rotation direction of the crucible.

9. The control method of the crystal furnace with integrated catcher according to claim 8, characterized in that: The controlling the first sliding block (42) to slide in a direction opposite to the rotation direction of the crucible specifically comprises the following steps: According to the real-time temperature uniformity, a pulling height and an updated coordinated sliding speed corresponding to the pulling height are obtained, wherein the pulling height is a height at which the catcher body (44) rises toward the side close to the furnace top plate; After the catcher body (44) is controlled to rise to the pulling height, the first sliding block (42) slides in a direction opposite to the rotation direction of the crucible at the updated coordinated sliding speed.

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