Thermal management system and method
By designing the thermal management system of the central processor and multiple thermostat components in the single crystal silicon growth system, the problem of thermal stress and mechanical stress in traditional systems is solved, and the stability of the single crystal silicon growth environment and Long life.
Patent Information
- Application Number
- CN202411476315.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-01-24
AI Technical Summary
During the growth of monocrystalline silicon, traditional thermal management systems are difficult to effectively regulate the heat source power, resulting in accumulation of thermal stress, increase in mechanical stress and damage to the sequel.
A heat management system is designed, including central processors and multiple temperature control components. Each temperature control component is equipped with temperature sensors and heater. The central processor can adjust the heater power in real time by obtaining temperature values, matching temperature curves, and calculating heating power adjustment instructions to maintain the single crystal silicon growth environment.
By accurately regulating the temperature, the damage to the heating impact on the cymbal is reduced, the stability of the single crystal silicon growth environment is maintained, and the service life of the Dangbang is prolonged.
Smart Images
Figure CN119352171A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor technology, and in particular to a thermal management system and method. Background Art
[0002] The challenges faced by the crucible during the traditional single crystal silicon growth process include the accumulation of thermal stress caused by high temperature thermal cycles, mechanical stress caused by frequent loading and unloading operations, the weakness of the material itself and the damage to the integrity of the crucible caused by improper operation processes, and the fact that the crucible can only be visually inspected after it is damaged. Therefore, how to adjust the heat source power during the single crystal silicon growth process is an urgent problem to be solved. Summary of the invention
[0003] The purpose of the embodiments of the present application is to provide a thermal management system and method for thermally managing the single crystal silicon growth process to maintain the single crystal silicon growth environment and reduce the damage to the crucible caused by thermal shock.
[0004] In a first aspect, the present invention provides a thermal management system, the system comprising a central processing unit and temperature control components arranged in multiple areas of a single crystal silicon preparation device, each temperature control component comprising at least one temperature sensor and at least one heater, wherein the central processing unit performs temperature control through the following steps: obtaining a collected temperature value sent by a target temperature sensor and a sensor identifier corresponding to the target temperature sensor; based on the sensor identifier, matching a temperature curve corresponding to the location of the target temperature sensor to determine a standard temperature value corresponding to a current growth stage of the single crystal silicon in the single crystal silicon preparation device; based on the collected temperature value and the standard temperature value, generating a heater power adjustment instruction and sending it to a target heater associated with the target temperature sensor, wherein the heater power adjustment instruction at least includes the heating power to be adjusted for the target heater.
[0005] In an optional embodiment, the system further includes an image sensor, and the central processor determines the standard temperature value in the following manner:
[0006] A sample image of the single crystal silicon generated by the image sensor is obtained to identify the current growth stage of the single crystal silicon; and a corresponding standard temperature value is matched in the temperature curve based on the current growth stage of the single crystal silicon.
[0007] In an optional embodiment, the central processor generates the heater power adjustment instruction in the following manner:
[0008] Calculate the temperature difference between the collected temperature value and the standard temperature value; bring the temperature difference into the PID calculation formula to calculate the heating power to generate a heater power adjustment instruction.
[0009] In an optional implementation, the PID calculation formula includes at least a proportional coefficient, an integral coefficient, and a differential coefficient, and the central processing unit adjusts the coefficients of the PID calculation formula in the following manner:
[0010] Calculate the historical temperature error value, which is the difference between the actual temperature value and the standard temperature value during the previous temperature control; determine whether the historical temperature error value is less than the preset temperature error value; if so, adjust the proportional coefficient according to the size and direction of the historical temperature error value; among which, the integral coefficient and the differential coefficient remain unchanged.
[0011] In an optional implementation, the CPU adjusts the scaling factor in the following manner:
[0012] Determine whether the historical temperature error value is less than zero; if so, reduce the proportional coefficient; if not, increase the proportional coefficient;
[0013] The step of reducing the proportionality coefficient specifically includes:
[0014] An error interval matched by the historical temperature error value is determined; and a proportionality factor is reduced based on an adjustment step matched by the error interval.
[0015] In an optional embodiment, for each target temperature sensor arranged at a different position in the single crystal silicon preparation device, the corresponding temperature curve is obtained by:
[0016] A single crystal silicon growth model is created and simulated to obtain the standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of single crystal silicon; a temperature curve is constructed based on the obtained standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of single crystal silicon.
[0017] In an optional embodiment, the temperature control component includes at least a first temperature control component, a second temperature control component and a third temperature control component, wherein the temperature sensor of the first temperature control component is arranged at the bottom of the crucible of the single crystal silicon preparation device, the temperature sensor of the second temperature control component is arranged evenly distributed on the side wall of the crucible of the single crystal silicon preparation device, and the temperature sensor of the third temperature control component is arranged at the top of the crucible of the single crystal silicon preparation device.
[0018] In an optional embodiment, the temperature control component further includes a fourth temperature control component, and the temperature sensor of the fourth temperature control component is distributed on the crystal growth plane in the single crystal silicon preparation device.
[0019] In a second aspect, the present invention provides a thermal management method, which includes obtaining a collected temperature value sent by a target temperature sensor and a sensor identifier corresponding to the target temperature sensor; based on the sensor identifier, matching a temperature curve corresponding to the location of the target temperature sensor to determine a standard temperature value corresponding to the current growth stage of single crystal silicon in a single crystal silicon preparation device; based on the collected temperature value and the standard temperature value, generating a heater power adjustment instruction and sending it to a target heater associated with the target temperature sensor, wherein the heater power adjustment instruction includes at least the heating power to be adjusted for the target heater.
[0020] In an optional embodiment, it also includes calculating a historical temperature error value, which is the difference between the actual temperature value and the standard temperature value during the previous temperature control; determining whether the historical temperature error value is less than a preset temperature error value; if so, adjusting the proportional coefficient of the PID calculation formula according to the size and direction of the historical temperature error value; wherein the PID calculation formula is used to calculate the heating power.
[0021] The present application provides a thermal management system and method, wherein the system includes a central processing unit and temperature control components arranged in multiple areas of a single crystal silicon preparation device, each temperature control component includes at least one temperature sensor and at least one heater, wherein the central processing unit performs temperature control through the following steps: obtaining the collected temperature value sent by the target temperature sensor and the sensor identification corresponding to the target temperature sensor; based on the sensor identification, matching the temperature curve corresponding to the location of the target temperature sensor to determine the standard temperature value corresponding to the current growth stage of the single crystal silicon in the single crystal silicon preparation device; based on the collected temperature value and the standard temperature value, generating a heater power adjustment instruction and sending it to the target heater associated with the target temperature sensor, wherein the production heater power adjustment instruction at least includes the heating power to be adjusted by the target heater. By thermally managing the single crystal silicon growth process, the single crystal silicon growth environment is maintained and the damage to the crucible caused by thermal shock is reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 A schematic diagram of the structure of a thermal management system provided in an embodiment of the present application;
[0024] Figure 2A flow chart of a temperature control method provided in an embodiment of the present application. DETAILED DESCRIPTION
[0025] First, the application scenario of the present application is described. The technical solution of the present application is applicable to the thermal management of a single crystal silicon preparation device during the process of cultivating single crystal silicon.
[0026] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.
[0027] Figure 1 This is a schematic diagram of the structure of a thermal management system provided in an embodiment of the present application. Figure 1 As shown, the thermal management system provided in the embodiment of the present application includes a central processing unit and temperature control components arranged in multiple areas of the single crystal silicon preparation device, and each temperature control component includes at least one temperature sensor and at least one heater.
[0028] Furthermore, the temperature control component includes at least a first temperature control component, a second temperature control component and a third temperature control component, wherein the temperature sensor of the first temperature control component is arranged at the bottom of the crucible of the single crystal silicon preparation device, the temperature sensor of the second temperature control component is arranged evenly distributed on the side wall of the crucible of the single crystal silicon preparation device, and the temperature sensor of the third temperature control component is arranged at the top of the crucible of the single crystal silicon preparation device.
[0029] It is understandable that the crucible of the single crystal silicon preparation device can be divided into different heights and positions to ensure that the temperature of each key area can be accurately monitored. For example, temperature sensors can be installed at the bottom, side walls and top of the crucible to ensure that the main heat flow path during the silicon crystal growth process is covered.
[0030] The temperature sensor of the first temperature control component is arranged at the bottom of the crucible of the single crystal silicon preparation device, close to the molten silicon material, to monitor the temperature of the melt and ensure the precise control of the melting process. The temperature sensor of the second temperature control component is evenly distributed on the side wall of the crucible of the single crystal silicon preparation device to monitor the side wall temperature, prevent deformation caused by local overheating, and support the uniformity control of the side wall temperature. The temperature sensor of the third temperature control component is arranged at the top of the crucible of the single crystal silicon preparation device to adjust the top environment, maintain a stable thermal field, and accurately manage the microenvironment of crystal growth.
[0031] A temperature sensor may also be arranged at the center of the crucible or near the single crystal silicon growth interface to more accurately control the temperature of the key growth area. That is, the temperature control component may also include a fourth temperature control component, and the temperature sensor of the fourth temperature control component is distributed on the crystal growth plane in the single crystal silicon preparation device. It is used to monitor and control the temperature of this key area in real time, which is very important to the crystal quality.
[0032] The heater of the first temperature control assembly can be arranged below the crucible, and can use a ring-shaped heating belt or a resistive heating element to ensure uniform heating of the bottom. The heater of the second temperature control assembly surrounds the heating element of the side wall of the crucible, and may use multiple independently controllable heating zones to adjust the heating intensity of each zone as needed. The heater of the third temperature control assembly can be arranged on the top of the crucible, especially for processes that need to maintain a specific top temperature.
[0033] It is understandable that the thermal management system may also include image sensors, pressure sensors, optical sensors, and the like.
[0034] Furthermore, in one embodiment of the present application, the crucible is divided into corresponding different temperature control zones according to different stages of single crystal silicon growth (such as melting, supercooling, early, middle and late growth stages) to meet the special requirements for temperature control in each growth stage. Figure 2 A flow chart of a temperature control method provided in an embodiment of the present application. Figure 2 As shown, the temperature sensor and heater are both electrically connected to the central processor, and the central processor performs temperature control through the following steps:
[0035] S1. Obtain the collected temperature value sent by the target temperature sensor and the sensor identifier corresponding to the target temperature sensor.
[0036] In order to achieve key point and partition control, temperature sensors at different locations are prefabricated with unique sensor identification, which can be ID, etc. The temperature sensor can collect temperature values at certain time intervals and upload them to the central processor.
[0037] S2. Based on the sensor identification, a temperature curve corresponding to the location of the target temperature sensor is matched to determine a standard temperature value corresponding to the current growth stage of the single crystal silicon in the single crystal silicon preparation device.
[0038] The central processing unit may store multiple temperature curves in advance. The temperature curves correspond to the temperature sensors one by one. The abscissa of the temperature curve may be the growth stage node of the single crystal silicon, and the ordinate may be the corresponding standard temperature value.
[0039] In step S2, the central processor can determine the standard temperature value in the following manner:
[0040] A sample image of the single crystal silicon generated by the image sensor is obtained to identify the current growth stage of the single crystal silicon. A corresponding standard temperature value is matched in the temperature curve based on the current growth stage of the single crystal silicon.
[0041] Here, the growth stage nodes of single crystal silicon can be identified through image recognition or through light source data collected by optical sensors.
[0042] S3. Based on the collected temperature value and the standard temperature value, generate a heater power adjustment instruction and send it to the target heater associated with the target temperature sensor.
[0043] In step S3, the corresponding heating power can be calculated according to the temperature difference of each key position point by an adaptive control algorithm. Specifically, the central processor generates a heater power adjustment instruction in the following manner:
[0044] Calculate the temperature difference between the collected temperature value and the standard temperature value. Substitute the temperature difference into the PID calculation formula to calculate the heating power to generate a heater power adjustment instruction. The production heater power adjustment instruction at least includes the heating power to be adjusted for the target heater.
[0045] The PID calculation formula can be expressed as:
[0046]
[0047] Among them, K p , K i , K d are the proportional coefficient, integral coefficient and differential coefficient respectively, ΔP is the heating power to be adjusted, and e(t) is the temperature difference.
[0048] The CPU can adjust the coefficients of the PID calculation formula in the following ways:
[0049] Calculate the historical temperature error value, which is the difference between the measured temperature value and the standard temperature value during the previous temperature control. Determine whether the historical temperature error value is less than the preset temperature error value. If so, adjust the proportional coefficient according to the size and direction of the historical temperature error value. Among them, the integral coefficient and the differential coefficient remain unchanged.
[0050] The CPU can adjust the scale factor in the following ways:
[0051] Determine whether the historical temperature error value is less than zero; if so, reduce the proportional coefficient; if not, increase the proportional coefficient; wherein the step of reducing the proportional coefficient specifically includes: determining the error interval matched by the historical temperature error value; and reducing the proportional coefficient based on the adjustment step matched by the error interval.
[0052] In a specific embodiment, K p , K i , K d The initial values of can be 1, 0.1, and 0.01 respectively. The preset temperature error value is 5°C / s.
[0053] The thermal management system and method provided in the embodiment of the present application achieves temperature uniformity in the silicon melting process and reduces thermal stress caused by local overheating by controlling the temperature of the single crystal silicon growth process. Combined with the dynamic thermal compensation system, the heat source power is automatically adjusted according to the actual heating situation to maintain an ideal growth environment and reduce the damage of thermal shock to the crucible.
[0054] In one embodiment of the present application, for each target temperature sensor arranged at different positions in the single crystal silicon preparation device, the corresponding temperature curve is obtained in the following manner:
[0055] Create a single crystal silicon growth model and perform simulation to obtain the standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of single crystal silicon. Construct a temperature curve based on the obtained standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of single crystal silicon.
[0056] Temperature curves are set for each area here. These curves are based on the physical model and empirical data of single crystal silicon growth. Partial differential equations are used to describe the changes of parameters such as temperature, concentration, stress, flow rate, etc. over time and space. For example, the energy conservation equation is used to describe the temperature distribution, the momentum conservation equation is used to describe the fluid dynamics, and the concentration diffusion equation is used to describe the distribution of impurities to ensure that the most suitable temperature conditions are maintained in each area throughout the growth cycle.
[0057] The different stages of single crystal silicon growth may include melting, supercooling, early growth, middle growth and late growth stages.
[0058] In one embodiment of the present application, the thermal management system may further include a refrigerator. For example, a pipeline for circulating cooling water or gas may be arranged near the area where the temperature needs to be reduced, especially the part close to the heat source but needs to maintain a lower temperature, to ensure the flexibility and accuracy of temperature control. The ambient temperature of the furnace chamber may also be maintained by an external cooling fan or air conditioning system to indirectly assist in controlling the internal thermal balance.
[0059] In one embodiment of the present application, in order to further ensure the stability of the growth environment of single crystal silicon, a new type of crucible material with high temperature resistance, high strength and optimized thermal expansion coefficient is provided, and its thermal stability and crack resistance are improved by doping special alloy elements in the substrate. At the same time, a new type of crucible geometry with a buffer structure can also be designed to disperse stress concentration points and reduce the impact of thermal shock.
[0060] In one embodiment of the present application, when there are multiple heaters in the temperature control assembly, the heating power indicated by the heater power adjustment instruction is the total heating power to be adjusted for the corresponding area in the single crystal silicon preparation device. For multiple heaters arranged in the area, the heating power corresponding to each heater can be calculated according to a preset weight, and then the corresponding heater can be controlled to adjust the power.
[0061] Based on the same inventive concept, an embodiment of the present application also provides a thermal management method applicable to a central processing unit, the method comprising:
[0062] Acquire the collected temperature value sent by the target temperature sensor and the sensor identifier corresponding to the target temperature sensor; based on the sensor identifier, match the temperature curve corresponding to the location of the target temperature sensor to determine the standard temperature value corresponding to the current growth stage of the single crystal silicon in the single crystal silicon preparation device; based on the collected temperature value and the standard temperature value, generate a heater power adjustment instruction and send it to the target heater associated with the target temperature sensor, wherein the heater power adjustment instruction at least includes the heating power to be adjusted for the target heater.
[0063] Furthermore, it also includes calculating a historical temperature error value, which is the difference between the actual temperature value and the standard temperature value during the previous temperature control; determining whether the historical temperature error value is less than a preset temperature error value; if so, adjusting the proportional coefficient of the PID calculation formula according to the size and direction of the historical temperature error value; wherein the PID calculation formula is used to calculate the heating power.
[0064] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.
[0065] In addition, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
[0066] Furthermore, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
[0067] It should be noted that if the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM) random access memory (RAM), disk or optical disk, and other media that can store program codes.
[0068] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.
[0069] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A thermal management system, characterized in that: The system includes a central processing unit and temperature control components arranged in multiple areas of a single crystal silicon preparation device, each temperature control component includes at least one temperature sensor and at least one heater, wherein: The central processing unit performs temperature control through the following steps: Obtaining the collected temperature value sent by the target temperature sensor and the sensor identifier corresponding to the target temperature sensor; Based on the sensor identifier, a temperature curve corresponding to the location of the target temperature sensor is matched to determine a standard temperature value corresponding to a current growth stage of the single crystal silicon in the single crystal silicon preparation device; Based on the collected temperature value and the standard temperature value, a heater power adjustment instruction is generated and sent to a target heater associated with a target temperature sensor, wherein the production heater power adjustment instruction at least includes a heating power to be adjusted for the target heater.
2. The system according to claim 1, characterized in that The system also includes an image sensor, and the central processor determines the standard temperature value in the following manner: acquiring a sample image of the single crystal silicon generated by an image sensor to identify a current growth stage of the single crystal silicon; A corresponding standard temperature value is matched in the temperature curve based on the current growth stage of the single crystal silicon.
3. The system according to claim 1, characterized in that The central processor generates the heater power adjustment instruction in the following manner: Calculating the temperature difference between the collected temperature value and the standard temperature value; The temperature difference is substituted into the PID calculation formula to calculate the heating power and generate a heater power adjustment instruction.
4. The system according to claim 3, characterized in that The PID calculation formula includes at least a proportional coefficient, an integral coefficient and a differential coefficient. The central processor adjusts the coefficients of the PID calculation formula in the following manner: Calculate a historical temperature error value, where the historical temperature error value is the difference between the actual temperature value during the previous temperature control and the standard temperature value; Determining whether the historical temperature error value is less than a preset temperature error value; If yes, adjusting the proportionality coefficient according to the magnitude and direction of the historical temperature error value; The integral coefficient and the differential coefficient remain unchanged.
5. The system according to claim 4, characterized in that The CPU adjusts the scale factor in the following manner: Determining whether the historical temperature error value is less than zero; If so, reducing the proportionality factor; If not, increasing the proportionality factor; The step of reducing the proportionality coefficient specifically includes: Determining an error interval matched by the historical temperature error value; The proportionality factor is reduced based on the adjustment step matched by the error interval.
6. The system according to claim 1, characterized in that For each target temperature sensor arranged at different positions in the single crystal silicon preparation device, the corresponding temperature curve is obtained in the following manner: Create a single crystal silicon growth model and perform simulation to obtain the standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of single crystal silicon; The temperature curve is constructed based on the acquired standard temperature values corresponding to different positions in the single crystal silicon preparation device at different growth stages of the single crystal silicon.
7. The system according to claim 1, characterized in that The temperature control component includes at least a first temperature control component, a second temperature control component and a third temperature control component, wherein the temperature sensor of the first temperature control component is arranged at the bottom of the crucible of the single crystal silicon preparation device, the temperature sensor of the second temperature control component is arranged evenly distributed on the side wall of the crucible of the single crystal silicon preparation device, and the temperature sensor of the third temperature control component is arranged at the top of the crucible of the single crystal silicon preparation device.
8. The system according to claim 7, characterized in that The temperature control component also includes a fourth temperature control component, and the temperature sensor of the fourth temperature control component is distributed on the crystal growth plane in the single crystal silicon preparation device.
9. A thermal management method, characterized in that: The method comprises: Obtaining the collected temperature value sent by the target temperature sensor and the sensor identifier corresponding to the target temperature sensor; Based on the sensor identifier, a temperature curve corresponding to the location of the target temperature sensor is matched to determine a standard temperature value corresponding to a current growth stage of the single crystal silicon in the single crystal silicon preparation device; Based on the collected temperature value and the standard temperature value, a heater power adjustment instruction is generated and sent to a target heater associated with a target temperature sensor, wherein the production heater power adjustment instruction at least includes a heating power to be adjusted for the target heater.
10. The method according to claim 9, characterized in that Also includes: Calculate a historical temperature error value, where the historical temperature error value is the difference between the actual temperature value during the previous temperature control and the standard temperature value; Determining whether the historical temperature error value is less than a preset temperature error value; If yes, then adjust the proportional coefficient of the PID calculation formula according to the size and direction of the historical temperature error value; The PID calculation formula is used to calculate the heating power.