Temperature control method for Czochralski single crystal silicon, electronic device, and Czochralski single crystal furnace

Abstract

The present disclosure relates to a temperature control method for a Czochralski single crystal silicon, an electronic device, and a Czochralski single crystal furnace. The method includes: when it is determined that the liquid surface temperature of the silicon melt in the crucible is within a preset temperature range, controlling a heating device to heat the silicon melt according to the seeding heating power of the silicon melt, and controlling the crucible to rotate at a varying rotational speed. In this way, by controlling the silicon melt to rotate at a varying rotational speed, the steady state formed by the silicon melt during the rotation of the crucible can be destroyed, facilitating heat exchange within the silicon melt, and further enabling the temperature of the silicon melt to quickly stabilize and reducing the temperature fluctuation of the silicon melt.

Description

Technical Field

[0001] The present disclosure relates to the technical field of single-crystal silicon preparation, and in particular, to a temperature control method for a Czochralski single-crystal silicon, an electronic device, and a Czochralski single-crystal furnace. Background Art

[0002] In Czochralski crystal pulling, silicon material is placed in a crucible in a single-crystal furnace, heated to melt the silicon material into silicon liquid, and then a seed crystal is immersed in the silicon liquid. By controlling the heating power and the pulling speed of the seed crystal, etc., the molten silicon liquid is allowed to grow along the seed crystal to form a single-crystal silicon rod.

[0003] After the temperature is adjusted, due to different initial conditions for adjusting the temperature, the temperature conditions of the silicon liquid after the temperature adjustment stage are different. The temperature of the silicon liquid fluctuates greatly during the stable temperature stage, and it is easy to cause diameter fluctuations of the single-crystal silicon rod during crystal seeding, affecting the stability of the diameter control of the single-crystal silicon rod and increasing the breakage rate of the single-crystal silicon rod. Summary of the Invention

[0004] The purpose of the present disclosure is to provide a temperature control method for a Czochralski single-crystal silicon, an electronic device, and a Czochralski single-crystal furnace, so as to enable the temperature of the silicon liquid to be quickly stabilized.

[0005] To achieve the above purpose, the present disclosure provides a temperature control method for a Czochralski single-crystal silicon, including:

[0006] When it is determined that the liquid surface temperature of the silicon liquid in the crucible is within a preset temperature range, control the heating device to heat the silicon liquid according to the crystal seeding heating power of the silicon liquid, and control the crucible to rotate at a varying rotation speed.

[0007] Optionally, the controlling the crucible to rotate at a varying rotation speed includes:

[0008] Determine a maximum rotation speed greater than the basic rotation speed and a minimum rotation speed less than the basic rotation speed of the crucible during crystal seeding of the silicon liquid;

[0009] Control the crucible to rotate at the current rotation speed, where the rotation speed varies between the maximum rotation speed and the minimum rotation speed.

[0010] Optionally, the determining a maximum rotation speed greater than the basic rotation speed and a minimum rotation speed less than the basic rotation speed of the crucible during crystal seeding of the silicon liquid includes:

[0011] Determine the maximum rotation speed and the minimum rotation speed according to the basic rotation speed and a preset rotation speed amplitude.

[0012] Optionally, controlling the crucible to rotate at the current rotation speed includes:

[0013] Cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed, wherein the duration of the crucible rotating at the maximum rotation speed is less than the duration of the crucible rotating at the minimum rotation speed.

[0014] Optionally, controlling the crucible to rotate at the current rotation speed further includes:

[0015] When the cyclic control of the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence reaches a first preset duration, controlling the crucible to continuously rotate at the basic rotation speed for a second preset duration.

[0016] Optionally, controlling the crucible to rotate at the current rotation speed further includes:

[0017] If it is detected that the temperature difference of the silicon liquid surface temperature within the second preset duration exceeds a preset difference threshold, the step of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence is re-executed.

[0018] Optionally, controlling the crucible to rotate at the current rotation speed further includes:

[0019] If it is detected that the temperature difference of the silicon liquid surface temperature within the second preset duration is less than or equal to the preset difference threshold and the temperature difference of the liquid surface temperature within a third preset duration after the second preset duration is less than or equal to the difference threshold, a preset crystal seeding control strategy is executed.

[0020] Optionally, controlling the crucible to rotate at the current rotation speed further includes:

[0021] Before executing the crystal seeding control strategy, it is determined that crystal points appear on the seed crystal in the silicon liquid within the third preset duration.

[0022] Optionally, controlling the crucible to rotate at the current rotation speed further includes:

[0023] Before executing the preset crystal seeding control strategy, it is determined that the number of times of controlling the crucible to continuously rotate at the basic rotation speed for the second preset duration exceeds or is equal to a preset number of times.

[0024] Optionally, the liquid surface temperature of the silicon liquid is determined by the following method:

[0025] Obtain the image information of the silicon liquid surface;

[0026] Determine the brightness information of the silicon liquid level according to the image information;

[0027] Determine the temperature of the liquid level according to the brightness information.

[0028] A second aspect of the present disclosure provides an electronic device, including:

[0029] A memory, on which a computer program is stored;

[0030] A processor, configured to execute the computer program in the memory to implement the steps of the method provided in the first aspect of the present disclosure.

[0031] A third aspect of the present disclosure provides a Czochralski single crystal furnace, including the electronic device provided in the second aspect of the present disclosure.

[0032] Through the above technical solutions, by controlling the silicon liquid to rotate at a variable rotational speed, the steady state formed during the rotation of the crucible can be destroyed, facilitating heat transfer within the silicon liquid. Furthermore, the temperature of the silicon liquid can be quickly stabilized, reducing the temperature fluctuation of the silicon liquid.

[0033] Specifically, when the liquid level temperature of the silicon liquid in the crucible is within a preset temperature range, the temperature adjustment of the silicon liquid ends, and the temperature of the silicon liquid is close to the seeding temperature of the silicon liquid. At this time, the heating device is controlled to heat the silicon liquid according to the seeding heating power of the silicon liquid. It can be understood that when the heating device heats the silicon liquid according to the seeding heating power, the temperature of the silicon liquid can be stabilized at the seeding temperature.

[0034] During the rotation of the crucible, the silicon liquid tends to reach a steady state at the current rotational speed. Therefore, during the heating process of the silicon liquid by the heating device, by controlling the crucible to rotate at a variable rotational speed, the steady state formed during the rotation of the crucible can be destroyed. By making the silicon liquid in a non-steady state, the heat transfer efficiency inside the silicon liquid is improved, facilitating the temperature uniformity within the silicon liquid. Furthermore, the temperature of the silicon liquid can be quickly stabilized, reducing the temperature fluctuation of the silicon liquid. In this way, by reducing the temperature fluctuation of the silicon liquid, the diameter fluctuation of the single crystal rod can be reduced, the stability of the control of the diameter of the single crystal rod can be improved, and the wire breakage rate of the single crystal rod can be reduced.

[0035] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation section. Description of the Drawings

[0036] The drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0037] Figure 1It is a flowchart of a temperature control method for Czochralski single crystal silicon provided by an exemplary embodiment of the present disclosure;

[0038] Figure 2 It is a flowchart of a temperature control method for Czochralski single crystal silicon provided by another exemplary embodiment of the present disclosure;

[0039] Figure 3 It is a graph showing the correspondence between the rotation speed of the crucible and time in the temperature control method for Czochralski single crystal silicon provided by an exemplary embodiment of the present disclosure;

[0040] Figure 4 It is a block diagram of an electronic device provided by an exemplary embodiment of the present disclosure. Detailed implementation manners

[0041] The following will describe the detailed implementation manners of the present disclosure in conjunction with the accompanying drawings. It should be understood that the detailed implementation manners described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0042] As described in the background art, in Czochralski crystal pulling, silicon material is placed in a crucible in a single crystal furnace, heated to melt the silicon material into silicon liquid, and then a seed crystal is immersed in the silicon liquid. By controlling the heating power and the pulling speed of the seed crystal, etc., the molten silicon liquid is allowed to grow along the seed crystal to form a single crystal silicon rod.

[0043] After the temperature adjustment is completed, due to different initial conditions for temperature adjustment, the temperature conditions of the silicon liquid after the temperature adjustment stage are different. The temperature of the silicon liquid fluctuates greatly during the stable temperature stage, and it is easy to cause fluctuations in the diameter of the single crystal silicon rod on the seed crystal during crystal seeding, affecting the stability of the diameter control of the single crystal silicon rod and increasing the wire breakage rate of the single crystal silicon rod.

[0044] At the same time, in the related art, the temperature of the silicon liquid can be determined by detecting the liquid surface temperature of the silicon liquid. However, there is a temperature difference between the liquid surface temperature of the silicon liquid and the temperature at the center of the silicon liquid, resulting in a strong lag in this detection method and increasing the difficulty of stabilizing the temperature of the silicon liquid.

[0045] Based on this, the present disclosure provides a temperature control method for Czochralski single crystal silicon, an electronic device, and a Czochralski single crystal furnace, which can quickly stabilize the temperature of the silicon liquid.

[0046] Figure 1 It is a flowchart of a temperature control method for Czochralski single crystal silicon provided by an exemplary embodiment of the present disclosure. Referring to Figure 1 , the embodiments of the present disclosure provide a temperature control method for single crystal silicon, and the method may include:

[0047] Step S1, when it is determined that the liquid surface temperature of the silicon liquid in the crucible is within a preset temperature range, control the heating device to heat the silicon liquid according to the crystal seeding heating power of the silicon liquid, and control the crucible to rotate at a changing rotation speed.

[0048] It is understandable that the seeding temperature of the silicon liquid can be within a preset temperature range. When the liquid surface temperature of the silicon liquid is within this temperature range, the liquid surface temperature of the silicon liquid is close to the seeding temperature. Therefore, during the heating process of the silicon liquid, if the liquid surface temperature of the silicon liquid is within this temperature range, the stable temperature stage of the silicon liquid can be entered at this time to stabilize the temperature of the silicon liquid.

[0049] In the stable temperature stage, the heating device (for example, an electric heating device) can be controlled to heat the silicon liquid according to the seeding heating power of the silicon liquid. It is understandable that when the heating device heats the silicon liquid according to the seeding heating power, the temperature of the silicon liquid can be stabilized at the seeding temperature.

[0050] During the rotation of the crucible, the silicon liquid in the crucible will tend to reach a steady state at the current rotation speed. Therefore, during the heating process of the silicon liquid by the heating device, by controlling the crucible to rotate at a varying rotation speed, the steady state formed by the silicon liquid during the rotation of the crucible can be disrupted. By making the silicon liquid in a non-steady state, the fluidity inside the silicon liquid is enhanced, the heat transfer efficiency inside the silicon liquid is improved, facilitating the uniform temperature inside the silicon liquid, and then the temperature of the silicon liquid can be quickly stabilized, reducing the temperature fluctuation of the silicon liquid. In this way, by reducing the temperature fluctuation of the silicon liquid, the diameter fluctuation of the single crystal silicon rod can be reduced, the stability of the control of the diameter of the single crystal silicon rod can be improved, and the wire breakage rate of the single crystal silicon rod can be reduced.

[0051] Figure 2 is a flowchart of a temperature control method for a Czochralski single crystal silicon provided by another exemplary embodiment of the present disclosure. Refer to Figure 2 , the above step S1 may include step S11 and step S12.

[0052] In step S11, according to the basic rotation speed of the crucible during the seeding of the silicon liquid, the maximum rotation speed greater than the basic rotation speed and the minimum rotation speed less than the basic rotation speed are determined.

[0053] In step S12, while controlling the heating device to heat the silicon liquid according to the seeding heating power of the silicon liquid, the crucible is controlled to rotate at the current rotation speed, wherein the rotation speed varies between the maximum rotation speed and the minimum rotation speed.

[0054] In this way, the rotation speed of the crucible can be near the basic rotation speed, and the state of the silicon liquid in the crucible can also be close to the state during seeding. Therefore, by determining the maximum rotation speed and the minimum rotation speed according to the basic rotation speed, it is convenient for the transition to the seeding stage after the temperature of the silicon liquid is stabilized.

[0055] Exemplarily, the step of determining the maximum rotation speed greater than the base rotation speed and the minimum rotation speed less than the base rotation speed according to the base rotation speed of the crucible during silicon liquid seeding may include: determining the maximum rotation speed and the minimum rotation speed according to the base rotation speed and a preset rotation speed amplitude.

[0056] For example, the base rotation speed can be added to the rotation speed amplitude to obtain the maximum rotation speed; the rotation speed amplitude can be subtracted from the base rotation speed to obtain the minimum rotation speed.

[0057] Figure 3 It is a corresponding relationship diagram of the rotation speed of the crucible and time in the temperature control method of pulling single crystal silicon provided by an exemplary embodiment of the present disclosure. Refer to Figure 3 , Figure 3 In the figure, the horizontal axis represents time, the vertical axis represents the rotation speed of the crucible, the solid line represents the change curve of the rotation speed of the crucible with time, r represents the base rotation speed, r1 represents the maximum rotation speed, and r2 represents the minimum rotation speed. Refer to Figure 3 Exemplarily, the step of controlling the crucible to rotate at the current rotation speed may include: cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed, wherein the rotation duration of the crucible at the maximum rotation speed is less than the rotation duration of the crucible at the minimum rotation speed.

[0058] It can be understood that when the crucible rotates at the base rotation speed, the silicon liquid in the crucible can maintain a uniform temperature. In this way, when the crucible rotates at the maximum rotation speed greater than the base rotation speed, the centrifugal force of the silicon liquid in the crucible increases, facilitating the transfer of heat in the silicon liquid from the center of the silicon liquid to the edge position of the crucible; similarly, when the crucible rotates at the minimum rotation speed less than the base rotation speed, it is convenient for the heat in the silicon liquid to be transferred from the edge position of the crucible to the center of the silicon liquid.

[0059] When controlling the heating device to heat the silicon liquid, the heating device can be controlled to heat the crucible, and the heat is transferred from the crucible to the silicon liquid. In this way, the silicon liquid at the edge position of the crucible is often at a higher temperature.

[0060] Therefore, during the process of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed, the rotation duration of the crucible at the maximum rotation speed is less than the rotation duration of the crucible at the minimum rotation speed, which is convenient for the heat to be transferred to the center of the silicon liquid, so that the heat can be quickly transferred from the crucible to the center of the silicon liquid, and the temperature of the silicon liquid can be quickly stabilized.

[0061] Exemplarily, the step of controlling the crucible to rotate at the current rotation speed may further include: when the crucible is cyclically controlled to rotate at the maximum rotation speed and the minimum rotation speed in sequence for a first preset duration, controlling the crucible to continuously rotate at the basic rotation speed for a second preset duration.

[0062] When the crucible is cyclically controlled to rotate at the maximum rotation speed and the minimum rotation speed in sequence for the first preset duration, sufficient heat exchange has occurred in the silicon melt at this time. Then, controlling the crucible to continuously rotate at the basic rotation speed for the second preset duration can make the silicon melt tend to a steady state, enabling the flow state of the silicon melt to meet the requirements of the crystal seeding stage and facilitating the transition to the crystal seeding stage.

[0063] Exemplarily, the step of controlling the crucible to rotate at the current rotation speed may further include: if it is detected that the temperature difference of the silicon melt liquid surface temperature exceeds a preset difference threshold within the second preset duration, then re-execute the step of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence.

[0064] Since the temperature of the liquid surface may not be the same as that at the center of the silicon melt, the liquid surface temperature has hysteresis. If it is detected that the temperature difference of the silicon melt liquid surface temperature exceeds the preset difference threshold within the second preset duration, the temperature difference between the liquid surface temperature and the temperature inside the silicon melt is relatively large at this time, and the temperature of the silicon melt has not yet stabilized. If crystal seeding is carried out at this time, it is likely to cause situations such as unstable diameter of the single crystal rod.

[0065] Therefore, if it is detected that the temperature difference of the silicon melt liquid surface temperature exceeds the preset difference threshold within the second preset duration, then re-execute the step of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence. At this time, the crucible can be cyclically controlled to rotate at the maximum rotation speed and the minimum rotation speed in sequence according to the Figure 3 shown implementation manner. When the crucible is cyclically controlled to rotate at the maximum rotation speed and the minimum rotation speed in sequence for the first preset duration, control the crucible to continuously rotate at the basic rotation speed for the second preset duration, and re-detect whether the temperature difference of the silicon melt liquid surface temperature exceeds the preset difference threshold within the second preset duration.

[0066] Exemplarily, the step of controlling the crucible to rotate at the current rotation speed further includes: if it is detected that the temperature difference of the silicon melt liquid surface temperature is less than or equal to the preset difference threshold within the second preset duration and the temperature difference of the liquid surface temperature within the third preset duration after the second preset duration is less than or equal to the difference threshold, then execute a preset crystal seeding control strategy.

[0067] If it is detected that the temperature difference of the silicon liquid surface temperature within the second preset duration is less than or equal to the preset difference threshold, it indicates that the temperature of the silicon liquid is stable within the second preset duration. At this time, it is possible to further detect whether the temperature difference of the liquid surface temperature within the third preset duration after the second preset duration is less than or equal to the difference threshold.

[0068] If the temperature difference of the liquid surface temperature within the third preset duration exceeds the difference threshold, it indicates that the temperature of the silicon liquid is not yet stable enough at this time. The steps of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence can be executed again. If the temperature difference of the liquid surface temperature within the third preset duration is less than or equal to the difference threshold, it indicates that the temperature of the silicon liquid is stable at this time, and the crystal seeding stage can be entered. Therefore, the preset crystal seeding control strategy can be executed at this time to grow a single crystal rod on the seed crystal.

[0069] Exemplarily, the step of controlling the crucible to rotate at the current rotation speed may further include: determining that crystal dots appear on the seed crystal in the silicon liquid within the third preset duration before executing the crystal seeding control strategy.

[0070] In this solution, if crystal dots appear on the seed crystal in the silicon liquid within the third preset duration, it indicates that the heating power of the current heating device and the temperature state of the silicon liquid can meet the growth requirements of single crystal silicon on the seed crystal at this time. Therefore, if crystal dots appear on the seed crystal in the silicon liquid within the third preset duration and the temperature difference of the liquid surface temperature within the third preset duration is less than or equal to the difference threshold, the crystal seeding stage can be entered.

[0071] If no crystal dots appear on the seed crystal in the silicon liquid within the third preset duration, it may be due to equipment aging, etc., resulting in a deviation between the current heating power and the crystal seeding heating power of single crystal silicon, or a reduction in the heat preservation performance of the single crystal furnace, or the temperature state of the current silicon liquid is not stable enough. Therefore, the steps of cyclically controlling the crucible to rotate at the maximum rotation speed and the minimum rotation speed in sequence can be executed again at this time to stabilize the temperature of the silicon liquid. Or, the heating power of the heating device can be readjusted to make the heating power of the heating device consistent with the crystal seeding heating power of single crystal silicon. Or, the heating power of the heating device can also be readjusted to make the state of the silicon liquid meet the requirements of the crystal seeding stage under the current heat preservation performance of the single crystal furnace.

[0072] Exemplarily, the step of controlling the crucible to rotate at the current rotation speed may further include: determining that the number of times the control crucible rotates at the basic rotation speed continuously for the second preset duration exceeds or is equal to the preset number of times before executing the preset crystal seeding control strategy.

[0073] For example, the preset number of times can be determined by experimental data or historical data. In this way, by controlling the crucible to continuously rotate at the basic rotation speed for a second preset time period exceeding or equal to the preset number of times, the temperature of the silicon liquid can be kept stable with a high probability, which can reduce the situation where the temperature of the silicon liquid is mistakenly considered to be stable when it is not stable due to measurement errors, thereby improving reliability.

[0074] Exemplarily, the liquid surface temperature of the silicon liquid can be determined by: acquiring image information of the silicon liquid surface; determining brightness information of the silicon liquid surface based on the image information; and determining the liquid surface temperature based on the brightness information.

[0075] For example, the correspondence between the brightness of the silicon liquid surface and the liquid surface temperature may be pre-stored. Thus, the liquid surface temperature of the silicon liquid may be determined based on the brightness information and the correspondence between the brightness of the silicon liquid surface and the liquid surface temperature.

[0076] Alternatively, in an alternative implementation, the liquid surface temperature of the silicon liquid may also be directly obtained by infrared temperature measurement.

[0077] Of course, controlling the crucible to rotate at a variable rotation speed is not limited to the above-mentioned embodiments. For example, the rotation direction of the crucible can also be changed, which facilitates the temperature transfer in the silicon liquid in the crucible. Alternatively, the crucible can be controlled to rotate by changing the rotation direction, and then the rotation speed is adjusted while maintaining the rotation direction, so that the temperature of the silicon liquid is finally stabilized.

[0078] In one embodiment of the present disclosure, during the process of adjusting the temperature of silicon liquid in the crucible, the liquid surface temperature of the silicon liquid can be obtained. If it is determined that the liquid surface temperature of the silicon liquid is within a preset temperature range, it means that the liquid surface temperature of the silicon liquid is close to the crystal seeding temperature of the silicon liquid. At this time, the temperature stabilization stage of the silicon liquid can be entered after a preset waiting time.

[0079] During the preset waiting time, the liquid surface temperature of the silicon liquid can be continuously monitored. If the liquid surface temperature of the silicon liquid exceeds the preset temperature range during the preset waiting time, the temperature of the silicon liquid can be readjusted at this time; if the liquid surface temperature of the silicon liquid continues to be within the preset temperature range during the preset waiting time, the temperature stabilization stage of the silicon liquid can be entered at this time. This can reduce the situation where the temperature stabilization stage is entered early due to the lag of the liquid surface temperature.

[0080] During the temperature stabilization stage of the silicon liquid, the heating device can be controlled to heat the silicon liquid according to the crystal seeding heating power of the silicon liquid. At the same time, the crucible can be controlled to rotate at a variable speed to break the steady state formed by the silicon liquid during the rotation of the crucible, increase the heat exchange inside the silicon liquid, and quickly stabilize the temperature of the silicon liquid.

[0081] Specifically, the maximum rotation speed and the minimum rotation speed can be determined first according to the basic rotation speed and amplitude of the crucible during silicon liquid seeding. For example, the maximum rotation speed can be obtained by adding the basic rotation speed and the amplitude, and the minimum rotation speed can be obtained by subtracting the amplitude from the basic rotation speed. For example, the basic rotation speed can be 7 r / min and the speed amplitude can be 0.5 r / min, then the maximum rotation speed can be 7.5 r / min and the minimum rotation speed can be 6.5 r / min.

[0082] Subsequently, the rotation duration T1 of the crucible at the maximum rotation speed, the rotation duration T2 of the crucible at the minimum rotation speed, the first preset duration for cyclically controlling the crucible to rotate at the maximum rotation speed for T1 and then at the minimum rotation speed for T2, the second preset duration for controlling the crucible to rotate continuously at the basic rotation speed, and the preset number of times for the crucible to rotate continuously at the basic rotation speed for the second preset duration can be determined.

[0083] If the liquid surface temperature of the silicon liquid continuously remains within the preset temperature range within the preset waiting time, at this time, the crucible can be cyclically controlled to rotate at the maximum rotation speed for a duration of T1 and at the minimum rotation speed for a duration of T2 within the first preset duration. For example, T1 can be 2 s, T2 can be 3 s, and the first preset duration can be 1 min.

[0084] When the crucible is cyclically controlled to rotate at the maximum rotation speed and then at the minimum rotation speed and reaches the first preset duration, control the crucible to rotate continuously at the basic rotation speed for the second preset duration. For example, the second preset duration can also be 1 min.

[0085] Controlling the crucible to rotate continuously at the basic rotation speed for the second preset duration can make the silicon liquid tend to be in a steady state; at the same time, the liquid surface temperature of the silicon liquid can also be observed within the second preset duration to determine whether the temperature of the silicon liquid is stable.

[0086] If the temperature difference of the liquid surface temperature of the silicon liquid is less than or equal to the preset difference threshold within the second preset duration and the number of times the crucible rotates continuously at the basic rotation speed for the second preset duration exceeds or is equal to the preset number of times, at this time, the temperature of the silicon liquid is basically stable, and the liquid surface temperature of the silicon liquid can be continuously monitored within the subsequent third preset duration (the third preset duration can be 10 - 15 min for example). If the temperature difference of the liquid surface temperature is less than or equal to the difference threshold within the third preset duration, at this time, it can be determined that the temperature of the silicon liquid is stable, and the seeding stage can be entered to execute the preset seeding control strategy.

[0087] Through the solution of this example, the steady state formed by the silicon liquid during the crucible rotation can be broken, which is convenient for rapid heat exchange inside the silicon liquid; at the same time, the hysteresis of the liquid surface temperature can be fully considered to accurately determine the temperature state of the silicon liquid according to the liquid surface temperature.

[0088] Figure 4 is a block diagram of an electronic device provided by an exemplary embodiment of the present disclosure. As Figure 4 shown, the electronic device 700 may include: a processor 701, a memory 702. The electronic device 700 may further include one or more of a multimedia component 703, an input / output (I / O) interface 704, and a communication component 705.

[0089] Among them, the processor 701 is used to control the overall operation of the electronic device 700 to complete all or part of the steps in the above-mentioned temperature control method for Czochralski single crystal silicon. The memory 702 is used to store various types of data to support the operation of the electronic device 700. These data may include, for example, instructions for any application or method operating on the electronic device 700, as well as application-related data, such as contact data, received and sent messages, pictures, audio, video, and so on. The memory 702 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The multimedia component 703 may include a screen and an audio component. Among them, the screen may be, for example, a touch screen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone, and the microphone is used to receive external audio signals. The received audio signals may be further stored in the memory 702 or sent through the communication component 705. The audio component further includes at least one speaker for outputting audio signals. The I / O interface 704 provides an interface between the processor 701 and other interface modules, and the above-mentioned other interface modules may be a keyboard, a mouse, buttons, etc. These buttons may be virtual buttons or physical buttons. The communication component 705 is used for wired or wireless communication between the electronic device 700 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, 4G, NB-IoT, eMTC, or other 5G, etc., or a combination of one or more of them, is not limited herein. Therefore, the corresponding communication component 705 may include: a Wi-Fi module, a Bluetooth module, an NFC module, and so on.

[0090] In one exemplary embodiment, the electronic device 700 may be implemented by one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components, and is used to execute the above-mentioned temperature control method for Czochralski single crystal silicon.

[0091] In another exemplary embodiment, a computer-readable storage medium including program instructions is further provided. When the program instructions are executed by a processor, the steps of the above-mentioned temperature control method for Czochralski single crystal silicon are implemented. For example, the computer-readable storage medium may be the above-mentioned memory 702 including program instructions, and the above-mentioned program instructions may be executed by the processor 701 of the electronic device 700 to complete the above-mentioned temperature control method for Czochralski single crystal silicon.

[0092] The present disclosure also provides a single crystal furnace including the electronic device provided in the above embodiments of the present disclosure.

[0093] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0094] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, without conflict, they can be combined in any appropriate manner. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.

[0095] In addition, any combination can be made between various different embodiments of the present disclosure, as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A temperature control method for Czochralski single crystal silicon, characterized in that, Including: When it is determined that the liquid surface temperature of the silicon liquid in the crucible is within a preset temperature range, it is determined that the liquid surface temperature of the silicon liquid is close to the seeding temperature. The heating device is controlled to heat the silicon liquid according to the seeding heating power of the silicon liquid, and the crucible is controlled to rotate at a varying rotational speed; Among them, the controlling the crucible to rotate at a varying rotational speed includes: Based on the basic rotational speed of the crucible during silicon liquid seeding, determine the maximum rotational speed greater than the basic rotational speed and the minimum rotational speed less than the basic rotational speed; Cyclically control the crucible to rotate at the maximum rotational speed and the minimum rotational speed, where the duration of the crucible rotating at the maximum rotational speed is less than the duration of the crucible rotating at the minimum rotational speed; When the cyclic control of the crucible rotating at the maximum rotational speed and the minimum rotational speed in sequence reaches a first preset duration, control the crucible to continuously rotate at the basic rotational speed for a second preset duration; If it is detected that the temperature difference of the liquid surface temperature of the silicon liquid exceeds a preset difference threshold within the second preset duration, re - execute the step of cyclically controlling the crucible to rotate at the maximum rotational speed and the minimum rotational speed in sequence; If it is detected that the temperature difference of the liquid surface temperature of the silicon liquid within the second preset duration is less than or equal to the preset difference threshold and the temperature difference of the liquid surface temperature within a third preset duration after the second preset duration is less than or equal to the difference threshold, then execute a preset seeding control strategy.

2. The method according to claim 1, characterized in that, The determining the maximum rotational speed greater than the basic rotational speed and the minimum rotational speed less than the basic rotational speed based on the basic rotational speed of the crucible during silicon liquid seeding includes: Based on the basic rotational speed and a preset rotational speed amplitude, determine the maximum rotational speed and the minimum rotational speed.

3. The method according to claim 1, wherein The controlling the crucible to rotate at the current rotational speed further includes: Before executing the seeding control strategy, determine that crystal points appear on the seed crystal in the silicon liquid within the third preset duration.

4. The method according to claim 1, characterized in that The controlling the crucible to rotate at the current rotational speed further includes: Before executing the preset seeding control strategy, determine that the number of times the crucible is continuously rotated at the basic rotational speed for the second preset duration exceeds or is equal to a preset number of times.

5. The method according to any one of claims 1 to 4, characterized in that The liquid surface temperature of the silicon liquid is determined by the following method: Obtain the image information of the silicon liquid surface; Based on the image information, determine the brightness information of the silicon liquid surface; Based on the brightness information, determine the liquid surface temperature.

6. An electronic device, characterized in that, Including: A memory on which a computer program is stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1 - 5.

7. A Czochralski single crystal furnace, characterized in that, Including the electronic device according to claim 6.

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