Furnace shutdown method and device of single crystal furnace, computer equipment, storage medium and program product

Abstract

The embodiment of the invention provides a blowing-out method of a single crystal furnace, and relates to the technical field of single crystal silicon. The method comprises the following steps: when the blowing-out duration of the single crystal furnace reaches a first duration, controlling a crucible to move upwards from a current position to a first preset position; when the furnace shutdown duration reaches a second duration, a guide cylinder is controlled to move upwards from the current position to a second preset position, the crucible is controlled to move downwards from the first preset position to a third preset position, and the third preset position is lower than the first preset position; and the position of the guide cylinder is kept unchanged at the second preset position, and the position of the crucible is kept unchanged at the third preset position until the blowing-out duration reaches a third duration. According to the embodiment of the invention, the blowing-out time can be shortened.

Description

Technical Field

[0001] The present application relates to the field of single crystal silicon technology, and in particular to a method, device, computer equipment, storage medium and program product for stopping a single crystal furnace. Background Art

[0002] Monocrystalline silicon is an important material for preparing solar cells in the photovoltaic industry, and is usually produced in a single crystal furnace. After the single crystal furnace is completed and shut down, in order to avoid local oxidation of the thermal field components due to high temperature, which will accelerate the aging of the thermal field components and affect the life of the thermal field components and increase production costs, the thermal field of the single crystal furnace needs to be fully cooled before the furnace can be dismantled.

[0003] In the prior art, after the furnace is shut down, a certain flow of argon gas is continuously passed through the single crystal furnace, and the thermal field of the single crystal furnace is fully cooled by natural cooling.

[0004] However, since the single crystal furnace used in the production of single crystal silicon is a sealed pressure vessel, the furnace contains many thermal field components and some thermal insulation felts. Among them, the thermal field components include guide tubes, upper insulation, middle insulation, lower insulation, heaters, crucibles, crucible supports, support rods, bottom pressure plates, bottom felts and other components. These thermal field components are combined into a bird's nest-like insulation system in the sealed single crystal furnace, which makes the thermal insulation effect of the thermal field components good, but the cooling speed is slow. For example, after the production of 36-inch single crystal silicon is completed, in order to fully cool the thermal field of the single crystal furnace, it is usually necessary to stop the furnace for 10 hours before the furnace can be dismantled. The entire shutdown time is long, which affects production efficiency. Summary of the invention

[0005] The embodiments of the present application provide a method device for stopping a single crystal furnace, a computer device, a storage medium and a program product to solve or alleviate one or more technical problems in the prior art.

[0006] As one aspect of an embodiment of the present application, an embodiment of the present application provides a method for stopping a single crystal furnace, comprising: When the shutdown time of the single crystal furnace reaches a first time, controlling the crucible to move from the current position to a first preset position; When the furnace shutdown time reaches a second time, the guide tube is controlled to move upward from the current position to a second preset position, and the crucible is controlled to move downward from the first preset position to a third preset position, wherein the third preset position is lower than the first preset position; The position of the guide tube is kept unchanged at the second preset position, and the position of the crucible is kept unchanged at the third preset position until the furnace shutdown time reaches the third time.

[0007] In one embodiment, when the furnace is shut down after the crystal pulling is completed, the flow rate of argon gas introduced into the single crystal furnace is controlled to increase from a first flow rate to a second flow rate; The argon gas flow rate is maintained at the second flow rate until the single crystal furnace is dismantled.

[0008] In one embodiment, the method further comprises: When the furnace is shut down after the crystal pulling is completed, the pressure in the single crystal furnace is controlled to increase from the first pressure to the second pressure; The pressure in the single crystal furnace is maintained at the second pressure until the single crystal furnace is dismantled.

[0009] In one embodiment, the first preset position is the top position to which the crucible can rise; and / or The second preset position is the top position to which the guide tube can rise; and / or The third preset position is the bottom position to which the crucible can descend.

[0010] In one embodiment, the first flow rate is 90-110 slpm, and the second flow rate is 200-300 slpm.

[0011] In one embodiment, the first pressure is 5-8 torr, and the second pressure is 40-300 torr.

[0012] In one implementation, the first duration is 40-90 minutes, the difference between the second duration and the first duration is 30-60 minutes, and the third duration is 5-7 hours.

[0013] The present application also provides a single crystal furnace shutdown device, the device comprising: A first control module is used to control the crucible to move from a current position to a first preset position when the shutdown time of the single crystal furnace reaches a first time; A second control module is used to control the guide tube to move from the current position to the second preset position, and control the crucible to move from the first preset position to the third preset position when the furnace shutdown time reaches the second time, and the third preset position is lower than the first preset position; The maintaining module is used to maintain the position of the guide tube at the second preset position unchanged, and maintain the position of the crucible at the third preset position unchanged, until the furnace shutdown time reaches a third time.

[0014] The present application also provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the computer program.

[0015] The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are implemented.

[0016] The present application also provides a computer program product, including a computer program, which implements the steps of the above method when executed by a processor.

[0017] The technical solution provided by the embodiment of the present application has the following advantages: The furnace shutdown method in the embodiment of the present application controls the crucible to move from the current position to the first preset position when the shutdown time of the single crystal furnace reaches the first time, so that the position of the crucible is closer to the position of the guide tube in the single crystal furnace, and the heat of the crucible is radiated to the guide tube more quickly through the heat radiation heat dissipation method, and then more heat is dissipated through the water cooling screen connected to the guide tube, so as to achieve the purpose of quickly reducing the crucible temperature, thereby shortening the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the guide tube is controlled to move from the current position to the second preset position, thereby increasing the distance between the guide tube and the crucible, preventing the guide tube from having an insulation effect on the crucible, thereby accelerating the heat dissipation speed, and further shortening the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the position of the crucible will be moved down from the first preset position to the third preset position, so that the position of the crucible is moved closer to the copper electrode, and the heat of the crucible, crucible support and other thermal field components can be dissipated faster through heat conduction heat dissipation, thereby further shortening the shutdown time. After actual verification, the shutdown method in the embodiment of the present application can shorten the normal shutdown time of a 36-inch large thermal field from more than 10 hours to within 7 hours compared to the shutdown method in the prior art. In addition, when the shutdown time is 7 hours and the furnace is dismantled, the temperature of the graphite parts in the single crystal furnace (the graphite parts with the highest temperature) will also be lower than 450°C, and will not affect the service life of the graphite parts. Therefore, the shutdown method in the embodiment of the present application can greatly shorten the shutdown time, thereby effectively improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0019] Figure 1 A schematic flow chart of a method for stopping a single crystal furnace according to an embodiment of the present application is shown.

[0020] Figure 2A program module diagram of an embodiment of a single crystal furnace shutdown device described in the present application; Figure 3 A schematic diagram of the hardware structure of a computer device for executing a single crystal furnace shutdown method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present application. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0022] Explanation of the name of this application: slpm is the abbreviation of "Standard Liters Per Minute". It is a flow unit used to measure the volume of gas or other fluid flowing per minute under standard conditions. The "standard conditions" here usually refer to a temperature of 0 degrees Celsius (273.15K) and a pressure of 1 atmosphere (101.325 kPa).

[0023] Torr, meaning "torr", is a unit of pressure used to measure the pressure of gases. 1 torr is equal to 1 mmHg, which is the pressure that can support a 1 mm high mercury column under standard atmospheric pressure. This unit is named after the Italian scientist Evangelista Torricelli, who first measured atmospheric pressure in the 17th century.

[0024] Figure 1 FIG. 1 is a schematic flow chart of a method for stopping a single crystal furnace according to an embodiment of the present application. Figure 1 As shown, the method for stopping the single crystal furnace includes: S100, when the shutdown time of the single crystal furnace reaches a first time, controlling the crucible to move from the current position to a first preset position.

[0025] In the prior art, when producing single crystal silicon in a single crystal furnace, after the crystal pulling is completed, the power supply of the heating system will be turned off, thus entering the shutdown stage. During the shutdown, in order to prevent the local oxidation of the thermal field components due to the high temperature, which will accelerate the aging of the thermal field components and thus affect the life of the thermal field components, a certain flow of argon gas will be continuously passed through the single crystal furnace.

[0026] The furnace shutdown method in the embodiment of the present application, under the premise that a certain flow rate of argon gas is always passed through the single crystal furnace, when the shutdown time of the single crystal furnace reaches a first time, further controls the crucible to move from the current position to the first preset position, so that the position of the crucible is closer to the position of the guide tube in the single crystal furnace. Since the temperature of the thermal field is high at the beginning of the shutdown, the heat radiation heat dissipation method will have a faster heat dissipation speed than the heat conduction heat dissipation method. In this way, by moving the position of the crucible closer to the position of the guide tube in the single crystal furnace at the beginning of the shutdown (the shutdown time reaches the first time), it is possible to achieve faster radiation of the heat of the crucible to the guide tube through the heat radiation heat dissipation method, and then dissipate more heat through the water cooling screen connected to the guide tube, so as to achieve the purpose of quickly reducing the crucible temperature, thereby shortening the shutdown time.

[0027] In addition, in the embodiment of the present application, by controlling the crucible to move from the current position to the first preset position only when the shutdown time of the single crystal furnace reaches a first time, rather than controlling the crucible to move from the current position to the first preset position when the single crystal furnace starts to shut down, it is possible to avoid a sudden drop in temperature of the single crystal silicon rod at the beginning of the shutdown, thereby reducing the risk of hidden cracks or explosion of the single crystal silicon rod.

[0028] In one embodiment, the crucible can be moved from the current position to the first preset position by manual control of the user. In another embodiment, the crucible can be automatically controlled by a computer device to move from the current position to the first preset position after the furnace shutdown time reaches the first time.

[0029] The first duration can be set and modified according to actual conditions. In a specific scenario, the first duration can be the time required for the single crystal silicon rod in the single crystal furnace to be pulled from its current position to the height corresponding to the first preset position after the furnace is shut down. It is understandable that the first duration can also be greater than the time required for the single crystal silicon rod to be pulled from its current position to the height corresponding to the first preset position.

[0030] The current position of the crucible is the position of the crucible when the single crystal furnace is just stopped.

[0031] The first preset position is a pre-set position and can be set and modified according to actual conditions.

[0032] S110, when the furnace shutdown time reaches a second time, controlling the guide tube to move up from the current position to a second preset position, and controlling the crucible to move down from the first preset position to a third preset position, wherein the third preset position is lower than the first preset position.

[0033] The second time length can be set and modified according to actual conditions. In a specific scenario, the second time length can be the time required for the heat dissipation rate of the heat radiation heat dissipation method in the single crystal furnace to begin to be lower than the heat dissipation rate of the heat conduction heat dissipation method when the single crystal furnace starts to stop for heat dissipation.

[0034] The current position of the guide tube is the position of the guide tube when the single crystal furnace is just shut down.

[0035] The second preset position is also a preset position and can be set and modified according to actual conditions.

[0036] The third preset position is also a preset position and can be set and modified according to actual conditions.

[0037] The shutdown method in the embodiment of the present application will further control the guide tube to move from the current position to the second preset position when the shutdown time of the single crystal furnace reaches the second time, thereby increasing the distance between the guide tube and the crucible, preventing the guide tube from having an insulating effect on the crucible, thereby accelerating the heat dissipation speed and shortening the shutdown time.

[0038] In addition, the furnace shutdown method in the embodiment of the present application will further control the crucible to move down from the first preset position to the third preset position when the shutdown time of the single crystal furnace reaches the second time, so that the position of the crucible is closer to the copper electrodes (generally 4) located at the bottom of the single crystal furnace and connected to cooling water. At this time, the heat conduction heat dissipation method has a faster heat dissipation speed than the thermal radiation heat dissipation method. In this way, by moving the position of the crucible closer to the position of the copper electrode when the shutdown time reaches the second time, the heat of the crucible, crucible support and other thermal field components can be dissipated faster through the heat conduction heat dissipation method, thereby shortening the shutdown time.

[0039] In one embodiment, the guide tube can be moved from the current position to the second preset position, and the crucible can be moved from the first preset position to the third preset position by manual control of the user. In another embodiment, after the furnace shutdown time reaches the second time, the guide tube can be automatically controlled by the computer to move from the current position to the second preset position, and the crucible can be automatically controlled to move from the first preset position to the third preset position.

[0040] It should be noted that during the movement, the guide tube or crucible can be moved to the desired position at a preset moving speed, or can be moved to the desired position directly in one step. The specific moving method is not limited in this embodiment.

[0041] S120, maintaining the position of the guide tube at the second preset position, and maintaining the position of the crucible at the third preset position, until the furnace shutdown time reaches a third time.

[0042] In the embodiment of the present application, after controlling the guide tube to move up to the second preset position and controlling the crucible to move down to the second preset position, the position of the guide tube will be kept unchanged at the second preset position, and the position of the crucible will be kept unchanged at the third preset position until the shutdown time reaches the third time, at which time the user can dismantle the single crystal furnace.

[0043] The third duration is the duration required for the entire shutdown process, and the third duration may also be set and adjusted according to actual conditions.

[0044] The furnace shutdown method in the embodiment of the present application controls the crucible to move from the current position to the first preset position when the shutdown time of the single crystal furnace reaches the first time, so that the position of the crucible is closer to the position of the guide tube in the single crystal furnace, and the heat of the crucible is radiated to the guide tube more quickly through the heat radiation heat dissipation method, and then more heat is dissipated through the water cooling screen connected to the guide tube, so as to achieve the purpose of quickly reducing the crucible temperature, thereby shortening the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the guide tube is controlled to move from the current position to the second preset position, thereby increasing the distance between the guide tube and the crucible, preventing the guide tube from having an insulation effect on the crucible, thereby accelerating the heat dissipation speed, and further shortening the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the position of the crucible will be moved down from the first preset position to the third preset position, so that the position of the crucible is moved closer to the copper electrode, and the heat of the crucible, crucible support and other thermal field components can be dissipated faster through heat conduction heat dissipation, thereby further shortening the shutdown time. After actual verification, the shutdown method in the embodiment of the present application can shorten the normal shutdown time of a 36-inch large thermal field from more than 10 hours to within 7 hours compared to the shutdown method in the prior art. In addition, when the shutdown time is 7 hours and the furnace is dismantled, the temperature of the graphite parts in the single crystal furnace (the graphite parts with the highest temperature) will also be lower than 450°C, and will not affect the service life of the graphite parts. Therefore, the shutdown method in the embodiment of the present application can greatly shorten the shutdown time, thereby effectively improving production efficiency.

[0045] In one embodiment, the method for shutting down the single crystal furnace further includes: when shutting down the furnace after crystal pulling is completed, controlling the argon flow rate entering the single crystal furnace to increase from a first flow rate to a second flow rate; maintaining the argon flow rate at the second flow rate unchanged until the single crystal furnace is dismantled.

[0046] In this embodiment, in order to further shorten the shutdown time, when the furnace is shut down after crystal pulling is completed, the argon flow rate entering the single crystal furnace can be controlled to increase from the first flow rate to the second flow rate, thereby increasing the argon flow rate entering the single crystal furnace during the shutdown stage, and then the argon gas can be used to take away the heat in the single crystal furnace more quickly through thermal convection, thereby accelerating the rate of temperature drop in the single crystal furnace and shortening the shutdown time.

[0047] The first flow rate is the flow rate introduced into the single crystal furnace when the furnace is shut down in the prior art. The first flow rate can be determined and modified according to actual conditions. The second flow rate is the increased flow rate. Generally speaking, the larger the second flow rate, the better. However, a larger flow rate consumes more argon, thereby increasing the cost of using argon. Therefore, in order to consider the cost factor, the second flow rate cannot be too large.

[0048] In one embodiment, the flow rate of argon gas introduced into the single crystal furnace can be increased from the first flow rate to the second flow rate by manual control of a user. In another embodiment, the flow rate of argon gas introduced into the single crystal furnace can be increased from the first flow rate to the second flow rate by automatic control of a computer device.

[0049] It should be noted that, in order to reduce the usage of argon, after the argon flow rate entering the single crystal furnace is increased from the first flow rate to the second flow rate, the argon flow rate may be simply maintained at the second flow rate for a preset time, without maintaining the argon flow rate at the second flow rate until the single crystal furnace is dismantled. The preset time can be set and modified according to actual conditions, and its specific value is not limited in this embodiment.

[0050] In one embodiment, the first flow rate is 90-110 slpm, including any point value within the flow rate range, for example, 90 slpm, 95 slpm, 100 slpm, 105 slpm, 110 slpm, etc.

[0051] The second flow rate is 200-300 slpm, including any value within the flow rate range, for example, 200 slpm, 220 slpm, 250 slpm, 270 slpm, 300 slpm, etc.

[0052] It should be noted that the first flow rate may also be less than 90 slpm or greater than 110 slpm. The second flow rate may also be less than 200 slpm or greater than 300 slpm.

[0053] In this embodiment, by setting the first flow rate to 90-110 slpm and the second flow rate to 200-300 slpm, it is possible to achieve a good heat convection heat dissipation speed without increasing the use cost of argon gas too much.

[0054] In one embodiment, the method for shutting down the single crystal furnace further includes: when shutting down the furnace after crystal pulling is completed, controlling the pressure in the single crystal furnace to increase from a first pressure to a second pressure; maintaining the pressure in the single crystal furnace at the second pressure until the single crystal furnace is dismantled.

[0055] In this embodiment, in order to further shorten the shutdown time, when the furnace is shut down after crystal pulling is completed, the pressure in the single crystal furnace can be controlled to increase from the first pressure to the second pressure, thereby forming faster local convection in the single crystal furnace, and then allowing the argon gas to take away the heat in the single crystal furnace more quickly through thermal convection, thereby accelerating the rate of temperature drop in the single crystal furnace and shortening the shutdown time.

[0056] In this embodiment, the pressure in the single crystal furnace can be adjusted from the first pressure to the second pressure by adjusting the opening of a throttle valve that controls the argon gas flow rate.

[0057] The first pressure is the pressure in the single crystal furnace when the furnace is shut down. The second pressure is the pressure after the pressure in the single crystal furnace is increased. Generally speaking, the greater the second pressure, the faster the local convection and the faster the heat loss rate. However, too fast a heat loss rate will cause a sudden drop in temperature in the single crystal furnace, thereby increasing the risk of hidden cracks or explosion of the single crystal silicon rod. Therefore, the second pressure cannot be too large.

[0058] In one embodiment, the pressure in the single crystal furnace can be raised from the first pressure to the second pressure by manual control of a user. In another embodiment, the pressure in the single crystal furnace can be raised from the first pressure to the second pressure by automatic control of a computer device.

[0059] In one embodiment, the first pressure is 5-8 torr, including any point value within the pressure range, for example, 5 torr, 5.5 torr, 6 torr, 7 torr, 8 torr, etc.

[0060] The second pressure is 40-300 torr, including any value within the pressure range, for example, 40 torr, 50 torr, 80 torr, 100 torr, 180 torr, 250 torr, 300 torr, etc.

[0061] It should be noted that the first pressure may also be less than 5 torr or greater than 8 torr. The second pressure may also be less than 40 torr or greater than 300 torr.

[0062] In this embodiment, by setting the first pressure to 5-8 torr and the second pressure to 40-300, it is possible to achieve a good heat convection heat dissipation speed without increasing the risk of hidden cracks or explosion of the single crystal silicon rod.

[0063] In one embodiment, in order to shorten the shutdown time as much as possible, the first preset position is the top position to which the crucible can rise, the second preset position is the top position to which the guide tube can rise, and the third preset position is the bottom position to which the crucible can descend.

[0064] It should be noted that the top position to which the crucible can rise as described above refers to the highest position to which the crucible can move during the up and down movement. The bottom position to which the crucible can descend as described above refers to the lowest position to which the crucible can move during the up and down movement. The top position to which the guide tube can rise as described above refers to the highest position to which the guide tube can move during the up and down movement.

[0065] In one embodiment, the first duration is 40-90 minutes, including any value within the time range, for example, 40 minutes, 50 minutes, 60 minutes, 80 minutes, 90 minutes, etc.

[0066] The difference between the second duration and the first duration is 30-60 minutes, including any point value within the difference range, for example, 30 minutes, 540 minutes, 40 minutes, 60 minutes, etc.

[0067] The third duration is 5-7 hours, including any value within this time range, for example, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, etc.

[0068] In this embodiment, by setting the first time length to 40-90 minutes and the difference between the second time length and the first time length to 30-60 minutes, the entire shutdown time is reduced from more than 10 hours to 5-7 hours.

[0069] In order to facilitate understanding that the shutdown method of the present application can shorten the shutdown time, the principle that the shutdown method of the present application can shorten the shutdown time is described in detail below.

[0070] 1. The principle that increasing the argon flow rate from the first flow rate (e.g. 100slpm) to the second flow rate (e.g. 200slpm) can reduce the shutdown time is: It is known that the specific heat capacity of argon gas Cp = 519.16 J / (kg.k) and the density of argon gas is 1.784 kg / m 3 , when the furnace is shut down, the argon flow rate is increased from 100slpm to 200slpm, then the mass of argon flowing through the single crystal furnace in one hour is: M 氩气 =1.784*200*60 / 1000=21.408kg.

[0071] Assuming that the temperature of argon entering the single crystal furnace is room temperature (25°C), the temperature at the outlet rises to 1200°C, and the temperature difference is 1175°C, then the heat absorbed and taken away per hour by argon with a flow rate of 200slpm is: Q 氩气 =c p M△T=519.16*21.408*(1200-25)=13059.158KJ.

[0072] Assuming the same conditions as above, the amount of heat that can be removed per hour by argon gas with a flow rate of 100slpm is: Q 原先 =(1.784*100*60 / 1000)*21.408*(1200-25)=6529.579KJ.

[0073] When the argon flow rate is increased from 100slpm to 200slpm during shutdown, the amount of heat that can be removed per hour is at least: Q 氩气- Q 原先 =6529.579KJ.

[0074] Therefore, by increasing the argon flow rate from the first flow rate to the second flow rate, the furnace shutdown time can be shortened.

[0075] 2. When the shutdown time of the single crystal furnace reaches a first time, the crucible is controlled to move from the current position to the first preset position; when the shutdown time reaches a second time, the guide tube is controlled to move from the current position to the second preset position, and the crucible is controlled to move from the first preset position to the third preset position. The principle of reducing the shutdown time is as follows: It is known that when the furnace is just shut down, the initial temperature in the furnace is 1450℃ (1723K), and the diameter of the guide tube surface is 330mm. The heat dissipation efficiency through thermal radiation is: W1=σεT1 4 =5.67*10 -8 *1723*1723*1723*1723*3.14*0.33*0.33 / 4=42719W.

[0076] It should be noted that σ represents the Stefan-Boltzmann constant, ε represents the emissivity of the object, and T represents the absolute temperature of the object.

[0077] When the furnace is just shut down, the heat radiated to the guide tube per hour is Q=42719*3600 / 1000=153788KJ.

[0078] When the temperature in the furnace is reduced to 500℃ (723K) for dismantling, the thermal radiation efficiency is: W2=σεAT2 4 =5.67*10 -8 *723*723*723*723*3.14*0.33*0.33 / 4=1324W.

[0079] At this time, the heat radiated to the guide tube per hour is Q=1324*3600 / 1000=4766KJ. It can be seen that the temperature is high when the furnace is just stopped, and the heat radiation efficiency is much higher than the heat radiation efficiency when the furnace is dismantled.

[0080] It is also known that the diameter of the copper electrodes (a total of 4) in the single crystal furnace is 90 mm, and the surface area of ​​the copper electrodes can be calculated to be S=πR 2 =3.14*90*90 / 4=63.585mm 2 . At the initial shutdown, the furnace temperature is 1450℃, and the copper electrode cooling water temperature is 40℃, so the temperature difference △T is 1450-40=1410℃, and the thermal conductivity of the graphite used is measured to be K=113 w / (m·k). The length of the graphite electrode d=100mm, according to the heat conduction calculation formula Q=KS△T / d, the thermal conductivity power of each copper electrode at the initial shutdown is calculated to be: W1=KS*△T1 / d=113*63.585*(1450-40) / 31 / 100=3260W=3.26KW.

[0081] When the furnace is dismantled, the temperature of each copper electrode is 450°C, so the thermal conductivity of each copper electrode is: W2=KS*△T2 / d=113*63.585*(450-40) / 31 / 100=950W.

[0082] Therefore, the average heat conduction of copper electrode cooling water per hour is: Q 电极 = (3260+950)*4*3600 / 2=30312KJ.

[0083] Through the above comparison of the heat dissipation speed of the heat radiation heat dissipation method and the heat conduction heat dissipation method, it can be known that in the initial period of the furnace shutdown, the heat dissipation speed of the heat radiation heat dissipation method is greater than the heat dissipation speed of the heat conduction heat dissipation method, and then, the heat dissipation speed of the heat radiation heat dissipation method will be lower than the heat dissipation speed of the heat conduction heat dissipation method. Therefore, in the embodiment of the present application, by controlling the crucible to move from the current position to the first preset position when the shutdown time of the single crystal furnace reaches the first time, so that the position of the crucible is closer to the position of the guide tube in the single crystal furnace, the heat of the crucible is radiated to the guide tube faster through the heat radiation heat dissipation method, and then more heat is dissipated through the water cooling screen connected to the guide tube. By controlling the guide tube to move from the current position to the second preset position when the shutdown time of the single crystal furnace reaches the second time, and the position of the crucible is moved down from the first preset position to the third preset position, so that the position of the crucible is moved closer to the position of the copper electrode, the heat of the heat field components such as the crucible and the crucible support can be dissipated faster through the heat conduction heat dissipation method, thereby shortening the shutdown time.

[0084] The following will test and calculate the conditions in the furnace at different shutdown times using the shutdown method in the prior art (Comparative Example 1) and the shutdown method in the present application (Example 1) to obtain the test results.

[0085] [Example 1] A single crystal furnace (model 160) was selected. After loading, vacuuming, seeding, shouldering, shoulder turning, equal diameter, and finishing, the power of the heating system was turned off to enter the shutdown stage. At the beginning of the shutdown, the argon flow rate into the single crystal furnace was increased from 100slpm to 200slpm, and at the same time, the pressure in the single crystal furnace was increased from 8 torr to 50 torr. After the shutdown time reaches 1 hour, the position of the crucible is moved up to the top position where it can be moved up. After the shutdown time reaches 1.5 hours, the position of the guide tube is moved up to the top position where it can be moved up, and the position of the crucible is moved down to the bottom position where it can be moved down. Continue to maintain the above state until the shutdown time reaches 10 hours, and then dismantle the furnace. During the 10-hour shutdown process, the furnace conditions with different shutdown times were detected and calculated, and the detection data shown in Table 1 were obtained.

[0086] Table 1

[0087] [Comparative Example 1] A single crystal furnace (model 160) was selected. After loading, vacuuming, seeding, shoulder placement, shoulder rotation, equal diameter, and finishing, the power of the heating system was turned off, thus entering the shutdown stage. During the shutdown stage, argon gas with a flow rate of 100slpm was continuously introduced into the single crystal furnace until the shutdown time reached 10 hours, and then the furnace was dismantled. During the 10-hour shutdown process, the furnace conditions with different shutdown times were detected and calculated, and the detection data shown in Table 2 were obtained.

[0088] Table 2

[0089] By comparing the detection data of Table 1 and Table 2, it can be seen that the temperature detected after 10 hours of shutdown by the shutdown method in the existing data is 597.50K, while the temperature detected after 5 hours by the shutdown method in the present application is 602.3K, which is only slightly greater than 597.50K. Therefore, after comparing the data, it can be seen that the shutdown method in the present application can greatly shorten the shutdown time and improve production efficiency compared with the shutdown method in the prior art.

[0090] See also Figure 2 , which is a program module diagram of an embodiment of a furnace stopping device 200 of a single crystal furnace of the present application.

[0091] In the embodiment of the present application, the single crystal furnace shutdown device 200 includes a series of computer program instructions stored in the memory. When the computer program instructions are executed by the processor, the shutdown function of the single crystal furnace in each embodiment of the present application can be implemented. In some embodiments, based on the specific operations implemented by each part of the computer program instructions, the single crystal furnace shutdown device 200 can be divided into one or more modules. The specific modules that can be divided are as follows: The first control module 201 is used to control the crucible to move from the current position to the first preset position when the shutdown time of the single crystal furnace reaches a first time.

[0092] The second control module 202 is used to control the guide tube to move from the current position to the second preset position and control the crucible to move from the first preset position to the third preset position when the furnace shutdown time reaches the second time. The third preset position is lower than the first preset position.

[0093] The maintaining module 203 is used to maintain the position of the guide tube at the second preset position, and maintain the position of the crucible at the third preset position, until the furnace shutdown time reaches a third time.

[0094] In one embodiment, the single crystal furnace shutdown device 200 further includes a creation module, a fourth control module, and a maintenance module.

[0095] The fourth control module is used to control the flow rate of argon gas introduced into the single crystal furnace from the first flow rate to the second flow rate when the furnace is shut down after crystal pulling is completed.

[0096] The maintaining module is used to maintain the argon gas flow rate at the second flow rate until the single crystal furnace is dismantled.

[0097] In one embodiment, the single crystal furnace shutdown device 200 further includes a fifth control module.

[0098] The fifth control module is used to control the pressure in the single crystal furnace to increase from the first pressure to the second pressure when the furnace is shut down after crystal pulling is completed.

[0099] The maintaining module is also used to maintain the pressure in the single crystal furnace at the second pressure until the single crystal furnace is dismantled.

[0100] In one embodiment, the first preset position is the top position to which the crucible can rise; and / or, the second preset position is the top position to which the guide tube can rise; and / or, the third preset position is the bottom position to which the crucible can descend.

[0101] In one embodiment, the first flow rate is 90-110 slpm, and the second flow rate is 200-300 slpm.

[0102] In one embodiment, the first pressure is 5-8 torr, and the second pressure is 40-300 torr.

[0103] In one implementation, the first duration is 40-90 minutes, the difference between the second duration and the first duration is 30-60 minutes, and the third duration is 5-7 hours.

[0104] The shutdown device of the single crystal furnace in the embodiment of the present application controls the crucible to move from the current position to the first preset position when the shutdown time of the single crystal furnace reaches the first time, so that the position of the crucible is closer to the position of the guide tube in the single crystal furnace, and the heat of the crucible is radiated to the guide tube more quickly through the heat radiation heat dissipation method, and then more heat is dissipated through the water cooling screen connected to the guide tube, so as to achieve the purpose of quickly reducing the crucible temperature and shorten the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the guide tube is controlled to move from the current position to the second preset position, thereby increasing the distance between the guide tube and the crucible, preventing the guide tube from having an insulation effect on the crucible, thereby accelerating the heat dissipation speed and further shortening the shutdown time. In addition, when the shutdown time of the single crystal furnace reaches the second time, the position of the crucible will be moved down from the first preset position to the third preset position, so that the position of the crucible is moved closer to the copper electrode, and the heat of the crucible, crucible support and other thermal field components can be dissipated faster through heat conduction heat dissipation, thereby further shortening the shutdown time. After actual verification, the shutdown method in the embodiment of the present application can shorten the normal shutdown time of a 36-inch large thermal field from more than 10 hours to within 7 hours compared to the shutdown method in the prior art. In addition, when the shutdown time is 7 hours and the furnace is dismantled, the temperature of the graphite parts in the single crystal furnace (the graphite parts with the highest temperature) will also be lower than 450°C, and will not affect the service life of the graphite parts. Therefore, the shutdown method in the embodiment of the present application can greatly shorten the shutdown time, thereby effectively improving production efficiency.

[0105] Figure 3 The hardware architecture diagram of a computer device 300 suitable for implementing a method for stopping a single crystal furnace according to an embodiment of the present application is schematically shown. In this embodiment, the computer device 300 is a device that can automatically perform numerical calculations and / or information processing according to pre-set or stored instructions. Figure 3 As shown, the computer device 300 includes at least but is not limited to: a memory 301, a processor 302, and a network interface 303 that can communicate with each other through a system bus. Among them: The memory 301 includes at least one type of computer-readable storage medium, which may be volatile or non-volatile. Specifically, the readable storage medium includes flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory, etc.), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, magnetic disk, optical disk, etc. In some embodiments, the memory 301 may be an internal storage module of the computer device 300, such as a hard disk or memory of the computer device 300. In other embodiments, the memory 301 may also be an external storage device of the computer device 300, such as a plug-in hard disk equipped on the computer device 300, a smart memory card (Smart Media Card, referred to as SMC), a secure digital (Secure Digital, referred to as SD) card, a flash card, etc. Of course, the memory 301 may also include both the internal storage module of the computer device 300 and its external storage device. In this embodiment, the memory 301 is generally used to store the operating system and various application software installed in the computer device 300, such as the program code of the single crystal furnace shutdown method, etc. In addition, the memory 301 can also be used to temporarily store various data that have been output or will be output.

[0106] In some embodiments, the processor 302 may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other single crystal furnace shutdown chips. The processor 302 is generally used to control the overall operation of the computer device 300, such as executing control and processing related to data interaction or communication with the computer device 300. In this embodiment, the processor 302 is used to run the program code stored in the memory 301 or process data.

[0107] The network interface 303 may include a wireless network interface or a wired network interface, and the network interface 303 is generally used to establish a communication link between the computer device 300 and other computer devices. For example, the network interface 303 is used to connect the computer device 300 to an external terminal through a network, and to establish a shutdown channel and a communication link of a single crystal furnace between the computer device 300 and the external terminal. The network may be a wireless or wired network such as an intranet, the Internet, the Global System of Mobile communication (GSM), Wideband Code Division Multiple Access (WCDMA), 4G network, 5G network, Bluetooth, Wi-Fi, etc.

[0108] It should be pointed out that Figure 3 Only a computer device having components 301 to 303 is shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0109] In this embodiment, the single crystal furnace shutdown method stored in the memory 301 can be divided into one or more program modules and executed by one or more processors (processor 302 in this embodiment) to complete the present application.

[0110] An embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for stopping a single crystal furnace in the embodiment are implemented.

[0111] In this embodiment, the computer-readable storage medium includes flash memory, hard disk, multimedia card, card-type memory (for example, SD or DX memory, etc.), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, etc. In some embodiments, the computer-readable storage medium may be an internal storage unit of a computer device, such as a hard disk or memory of the computer device. In other embodiments, the computer-readable storage medium may also be an external storage device of a computer device, such as a plug-in hard disk equipped on the computer device, a smart memory card (Smart Media Card, referred to as SMC), a secure digital (Secure Digital, referred to as SD) card, a flash card, etc. Of course, the computer-readable storage medium may also include both an internal storage unit of a computer device and an external storage device thereof. In this embodiment, the computer-readable storage medium is generally used to store an operating system and various application software installed on a computer device, such as the program code of the method for stopping a single crystal furnace in the embodiment, etc. In addition, the computer-readable storage medium may also be used to temporarily store various types of data that have been output or are to be output.

[0112] An embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method for stopping a single crystal furnace in the embodiment.

[0113] In the description of this specification, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0114] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0115] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0116] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0117] The disclosure above provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described above. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numerals and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed.

[0118] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for stopping a single crystal furnace, characterized in that: include: When the shutdown time of the single crystal furnace reaches a first time, controlling the crucible to move from the current position to a first preset position; When the furnace shutdown time reaches a second time, the guide tube is controlled to move upward from the current position to a second preset position, and the crucible is controlled to move downward from the first preset position to a third preset position, wherein the third preset position is lower than the first preset position; The position of the guide tube is kept unchanged at the second preset position, and the position of the crucible is kept unchanged at the third preset position until the furnace shutdown time reaches the third time.

2. The method according to claim 1, characterized in that The method further comprises: When the furnace is shut down after the crystal pulling is completed, the flow rate of argon gas introduced into the single crystal furnace is controlled to increase from the first flow rate to the second flow rate; The argon gas flow rate is maintained at the second flow rate until the single crystal furnace is dismantled.

3. The method according to claim 2, characterized in that The method further comprises: When the furnace is shut down after the crystal pulling is completed, the pressure in the single crystal furnace is controlled to increase from the first pressure to the second pressure; The pressure in the single crystal furnace is maintained at the second pressure until the single crystal furnace is dismantled.

4. The method according to any one of claims 1 to 3, characterized in that: The first preset position is the top position to which the crucible can rise; and / or The second preset position is the top position to which the guide tube can rise; and / or The third preset position is the bottom position to which the crucible can descend.

5. The method according to claim 2, characterized in that: The first flow rate is 90-110 slpm, and the second flow rate is 200-300 slpm.

6. The method according to claim 3, characterized in that The first pressure is 5-8 torr, and the second pressure is 40-300 torr.

7. The method according to any one of claims 1 to 3, characterized in that: The first duration is 40-90 minutes, the difference between the second duration and the first duration is 30-60 minutes, and the third duration is 5-7 hours.

8. A single crystal furnace shutdown device, characterized in that: The device comprises: A first control module is used to control the crucible to move from a current position to a first preset position when the shutdown time of the single crystal furnace reaches a first time; A second control module is used to control the guide tube to move from the current position to the second preset position, and control the crucible to move from the first preset position to the third preset position when the furnace shutdown time reaches the second time, and the third preset position is lower than the first preset position; The maintaining module is used to maintain the position of the guide tube at the second preset position unchanged, and maintain the position of the crucible at the third preset position unchanged, until the furnace shutdown time reaches a third time.

9. A computer device, characterized in that: The computer device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

11. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images