Heat treatment apparatus and control method for a heat treatment apparatus

Abstract

The application provides a heat treatment device and a control method thereof. The heat treatment device comprises a furnace tube, a heating assembly, an inner temperature measuring unit, an outer temperature measuring unit and an intermediate temperature measuring unit. The furnace tube is internally formed with a heat treatment cavity. The heating assembly is arranged outside the furnace tube and is configured to emit thermal radiation towards the heat treatment cavity to provide heat for the heat treatment cavity. The inner temperature measuring unit is located in the heat treatment cavity. The outer temperature measuring unit is located between the heating assembly and the furnace tube. The intermediate temperature measuring unit is located between the inner temperature measuring unit and the outer temperature measuring unit in the radial direction of the furnace tube. By arranging the intermediate temperature measuring unit between the inner temperature measuring unit and the outer temperature measuring unit in the radial direction of the furnace tube, whether the inner temperature measuring unit or the outer temperature measuring unit fails can be determined by determining whether the difference between the temperature values fed back by the inner temperature measuring unit and the intermediate temperature measuring unit and the difference between the temperature values fed back by the outer temperature measuring unit and the intermediate temperature measuring unit deviate from the normal temperature gradient, thereby ensuring the stability of the heat treatment device during operation and the reliability of the heat treatment device.

Description

Technical Field

[0001] This application relates to the fields of photovoltaic and semiconductor technology, and more specifically to a heat treatment apparatus and a control method for the heat treatment apparatus. Background Technology

[0002] In the production of photovoltaic cells, silicon wafers undergo multiple high-temperature chemical heat treatment processes, such as diffusion junction formation, chemical vapor deposition (CVD), and annealing repair. The diffusion junction formation process allows the formation of PN junctions within the silicon wafer. The low-pressure chemical vapor deposition (LPCVD) process enables the fabrication of key structures such as silicon nitride thin films, tunneling layers, or passivation layers on the silicon wafer.

[0003] Heat treatment apparatuses in related technologies typically include a furnace tube containing a heat treatment chamber where silicon wafers are placed for heat treatment processes. To obtain the temperature within the heat treatment chamber, some heat treatment apparatuses incorporate a temperature measuring unit. This unit monitors the temperature inside the chamber. Based on the temperature readings from the measuring unit, the heat treatment apparatus can adjust the power of the heating elements accordingly to maintain the temperature within the heat treatment chamber at a target value. However, heat treatment apparatuses can experience instability during operation, such as abnormally increasing or decreasing the power of the heating elements, resulting in insufficient reliability.

[0004] Therefore, there is an urgent need for a method that can ensure the stability of the heat treatment equipment during operation, so as to ensure the reliability of the heat treatment equipment. Summary of the Invention

[0005] In view of this, the present application provides a heat treatment apparatus and a control method for the heat treatment apparatus, which can ensure the stability of the heat treatment apparatus during operation, thereby ensuring the reliability of the heat treatment apparatus.

[0006] In a first aspect, embodiments of this application provide a heat treatment apparatus, comprising: a furnace tube having a heat treatment cavity formed therein; a heating assembly disposed outside the furnace tube, the heating assembly being configured to emit thermal radiation toward the heat treatment cavity to provide heat to the heat treatment cavity; an inner temperature measuring unit located inside the heat treatment cavity; an outer temperature measuring unit located between the heating assembly and the furnace tube; and an intermediate temperature measuring unit located radially along the furnace tube, the intermediate temperature measuring unit being located between the inner temperature measuring unit and the outer temperature measuring unit.

[0007] In some embodiments, the heat treatment apparatus further includes a controller configured to: acquire temperature values ​​fed back by the internal temperature measuring unit, the external temperature measuring unit, and the intermediate temperature measuring unit; calculate a first difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; calculate a second difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; and compare the first difference and the second difference with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measuring unit and the external temperature measuring unit are abnormal, wherein the first preset interval is a predetermined range of differences between the internal temperature measuring unit and the intermediate temperature measuring unit when the internal temperature measuring unit is working normally, and the second preset interval is a predetermined range of differences between the external temperature measuring unit and the intermediate temperature measuring unit when the external temperature measuring unit is working normally.

[0008] In some embodiments, the heating assembly includes a plurality of heating sections arranged along the axial direction of the furnace tube, wherein the power of each heating section can be independently adjusted, and the heat treatment apparatus includes a plurality of internal temperature measuring units, a plurality of external temperature measuring units, and a plurality of intermediate temperature measuring units, wherein the plurality of internal temperature measuring units, the plurality of external temperature measuring units, and the plurality of intermediate temperature measuring units correspond one-to-one with the plurality of heating sections along the axial direction of the furnace tube.

[0009] In some embodiments, the furnace tube includes an inner tube and an outer tube that are coaxially nested, the heat treatment chamber is formed by the inner wall of the inner tube, there is an annular interlayer space between the inner tube and the outer tube, the plurality of intermediate temperature measuring units are disposed in the annular interlayer space, and the annular interlayer space is a vacuum or filled with inert gas.

[0010] In some embodiments, the heat treatment apparatus further includes a preheating component configured to preheat the reaction gas or inert gas before introducing it into the heat treatment chamber.

[0011] In some embodiments, the furnace tube is provided with an exhaust valve that communicates with the heat treatment chamber.

[0012] Secondly, embodiments of this application provide a control method for a heat treatment apparatus, applied to the heat treatment apparatus. The heat treatment apparatus includes: a furnace tube, within which a heat treatment chamber is formed; a heating assembly, coaxially sleeved outside the furnace tube and spaced apart from it, the heating assembly being configured to emit thermal radiation toward the heat treatment chamber to provide heat to the heat treatment chamber; an inner temperature measuring unit located within the heat treatment chamber; an outer temperature measuring unit located between the heating assembly and the furnace tube; and an intermediate temperature measuring unit located radially along the furnace tube, between the inner and outer temperature measuring units. The control method for the heat treatment apparatus includes: acquiring temperature values ​​fed back by the internal temperature measuring unit, the external temperature measuring unit, and the intermediate temperature measuring unit; calculating a first difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; calculating a second difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; and comparing the first difference and the second difference with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measuring unit and the external temperature measuring unit are abnormal, wherein the first preset interval is a predetermined range of differences between the temperature values ​​fed back by the internal temperature measuring unit and the temperature values ​​fed back by the intermediate temperature measuring unit when the internal temperature measuring unit is working normally, and the second preset interval is a predetermined range of differences between the temperature values ​​fed back by the external temperature measuring unit and the temperature values ​​fed back by the intermediate temperature measuring unit when the external temperature measuring unit is working normally.

[0013] In some embodiments, comparing the first difference and the second difference with a first preset interval and a second preset interval respectively to determine whether the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the external temperature measuring unit are abnormal includes: determining whether the first difference and the second difference are respectively located within the first preset interval and the second preset interval; if the first difference is not located within the first preset interval but the second difference is located within the second preset interval, then determining that the temperature value fed back by the internal temperature measuring unit is abnormal and the temperature value fed back by the external temperature measuring unit is normal; if the first difference is located within the first preset interval but the second difference is not located within the second preset interval, then determining that the temperature value fed back by the internal temperature measuring unit is normal and the temperature value fed back by the external temperature measuring unit is abnormal.

[0014] In some embodiments, the first difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit, and the second difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit. The first preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit when the internal temperature measurement unit is working normally. The second preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit when the external temperature measurement unit is working normally. When it is determined that the temperature value fed back by the internal temperature measuring unit is abnormal while the temperature value fed back by the external temperature measuring unit is normal, the control method further includes: comparing the first difference with the upper limit and lower limit of the first preset interval respectively; when the first difference is lower than the lower limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is lower than the actual temperature value at the internal temperature measuring unit; when the first difference is higher than the upper limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is higher than the actual temperature value at the internal temperature measuring unit; and / or, when it is determined that the temperature value fed back by the internal temperature measuring unit is normal while the temperature value fed back by the external temperature measuring unit is abnormal, the control method further includes: comparing the second difference with the upper limit and lower limit of the second preset interval respectively; when the second difference is lower than the lower limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is lower than the actual temperature value at the external temperature measuring unit; when the second difference is higher than the upper limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is higher than the actual temperature value at the external temperature measuring unit.

[0015] In some embodiments, comparing the first difference and the second difference with a first preset interval and a second preset interval respectively to determine whether the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the external temperature measuring unit are abnormal, further includes: if the first difference is not within the first preset interval and the second difference is not within the second preset interval, then determining whether the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the external temperature measuring unit are abnormal based on the operating status parameters of the heat treatment device, wherein the operating status parameters of the heat treatment device include at least one of the power of the heating component and the uniformity of the process result of the product.

[0016] In some embodiments, when the heating assembly includes a plurality of heating sections arranged axially along the furnace tube, the power of each of the plurality of heating sections is independently adjustable, and the heat treatment apparatus includes a plurality of internal temperature measuring units, a plurality of external temperature measuring units, and a plurality of intermediate temperature measuring units, wherein the plurality of internal temperature measuring units, the plurality of external temperature measuring units, and the plurality of intermediate temperature measuring units correspond one-to-one with the plurality of heating sections along the axial direction of the furnace tube, the control method further includes: acquiring temperature values ​​fed back by the plurality of internal temperature measuring units; comparing the temperature value fed back by each of the plurality of internal temperature measuring units with a target temperature value; if the temperature value fed back by the internal temperature measuring unit is lower than the target temperature value, increasing the power of the heating section corresponding to the internal temperature measuring unit; and if the temperature value fed back by the internal temperature measuring unit is higher than the target temperature value, decreasing the power of the heating section corresponding to the internal temperature measuring unit.

[0017] In some embodiments, when the heat treatment apparatus further includes a preheating component configured to preheat the reactant gas or inert gas before introducing it into the heat treatment chamber, the control method further includes: comparing the temperature values ​​fed back by each of the plurality of internal temperature measuring units; if the difference between the temperature values ​​fed back by any two of the plurality of internal temperature measuring units is greater than 3°C, then controlling the preheating component to preheat the reactant gas or inert gas to a target temperature range before introducing it into the heat treatment chamber, wherein the upper limit of the target temperature range is the target temperature value + 5°C, and the lower limit of the target temperature range is the target temperature value - 5°C.

[0018] In some embodiments, the control method further includes: during the process of the temperature in the heat treatment chamber rising from room temperature to a target temperature value, acquiring the temperature value fed back by the external temperature measurement unit, and adjusting the power of the heating component based on a PID control algorithm until the temperature in the heat treatment chamber rises to 90% of the target temperature.

[0019] In some embodiments, when the furnace tube is provided with an exhaust valve communicating with the heat treatment chamber, the control method further includes: during the process of the temperature in the heat treatment chamber decreasing from a target temperature value to room temperature, acquiring the temperature value fed back by the internal temperature measuring unit and calculating the rate of decrease of the temperature value fed back by the internal temperature measuring unit, and adjusting the opening of the exhaust valve so that the rate of decrease of the temperature value fed back by the internal temperature measuring unit is 5℃ / min~10℃ / min.

[0020] According to the heat treatment apparatus and control method provided in the embodiments of this application, since the heating component is located outside the furnace tube and emits thermal radiation toward the heat treatment chamber to provide heat to the heat treatment chamber, a temperature gradient with gradually decreasing temperature from the outside to the inside is formed in the radial direction of the furnace tube. That is, under normal operating conditions, there is a stable gradient correlation between the temperature values ​​fed back by the inner temperature measuring unit, the intermediate temperature measuring unit, and the outer temperature measuring unit. By arranging the intermediate temperature measuring unit radially between the inner and outer temperature measuring units, based on the temperature gradient and using the temperature value fed back by the intermediate temperature measuring unit as a reference, it is possible to infer whether the inner or outer temperature measuring unit has malfunctioned by determining whether the difference between the temperature value fed back by the inner and intermediate temperature measuring units, and the difference between the temperature value fed back by the outer and intermediate temperature measuring units, deviates from the normal temperature gradient. This ensures the stability of the heat treatment apparatus during operation and guarantees its reliability. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a heat treatment apparatus provided in an embodiment of this application.

[0022] Figure 2 This diagram illustrates the structure of multiple heating elements arranged axially along the furnace tube.

[0023] Figure 3 This diagram illustrates the structure of multiple internal temperature measurement units housed within a sleeve.

[0024] Figure 4 This is a schematic diagram showing the structure of the inner wall of the inner tube with a layer of by-products deposited on it.

[0025] Figure 5 This is a schematic diagram of the structure of a control method for a heat treatment apparatus provided in an embodiment of this application.

[0026] Explanation of reference numerals in the attached drawings: 100, heat treatment device; 10, furnace tube; 11, inner tube; 111, heat treatment chamber; 112, by-product adhesion layer; 12, outer tube; 13, annular interlayer space; 14, exhaust valve; 20, heating component; 21, heating section; 30, internal temperature measuring unit; 40, external temperature measuring unit; 50, intermediate temperature measuring unit; 60, controller; 70, preheating component; 80, sleeve; 90, wire. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] Although the heat treatment device controls the temperature based on the temperature value fed back by the temperature measuring unit, it still has the problem of instability during operation, resulting in insufficient reliability.

[0029] To address the aforementioned problems, the inventors, through in-depth research, discovered that the instability of the heat treatment apparatus during operation stems from malfunctions in both the internal and external temperature measurement units, resulting in incorrect temperature readings. During the heat treatment process on silicon wafers, the environment within the heat treatment chamber is constantly changing and complex. Therefore, the internal temperature measurement unit, located within the heat treatment chamber, is prone to malfunction after prolonged exposure to this variable and complex environment. Furthermore, the external temperature measurement unit, being close to the heating element, is also susceptible to malfunction after prolonged exposure to high temperatures. When the internal and external temperature measurement units malfunction, the temperature values ​​they report are not the actual temperatures at their respective measurement points. Consequently, the heat treatment apparatus adjusts the power of the heating element based on these incorrect temperature values, failing to achieve the appropriate power level.

[0030] To this end, after numerous attempts, the inventors have finally creatively proposed a heat treatment device and a control method for the heat treatment device, which can promptly determine whether the internal and external temperature measuring units have malfunctioned, thereby ensuring the stability of the heat treatment device during operation and thus guaranteeing the reliability of the heat treatment device.

[0031] Figure 1 This is a schematic diagram of a heat treatment apparatus 100 provided in an embodiment of this application. The heat treatment apparatus 100 includes a furnace tube 10, a heating assembly 20, an inner temperature measuring unit 30, an outer temperature measuring unit 40, and an intermediate temperature measuring unit 50. A heat treatment chamber 111 is formed inside the furnace tube 10. The heating assembly 20 is disposed outside the furnace tube 10 and configured to emit thermal radiation toward the heat treatment chamber 111 to provide heat to the heat treatment chamber 111. The inner temperature measuring unit 30 is located inside the heat treatment chamber 111. The outer temperature measuring unit 40 is located between the heating assembly 20 and the furnace tube 10. In the radial direction of the furnace tube 10, the intermediate temperature measuring unit 50 is located between the inner temperature measuring unit 30 and the outer temperature measuring unit 40.

[0032] The furnace tube 10 can be made of quartz, for example, high-purity quartz. Quartz tubes have excellent high-temperature resistance and can withstand temperatures above 1200℃.

[0033] The temperature measuring unit is configured to collect the temperature at a designated measuring point. The measuring point of the inner temperature measuring unit 30 is located inside the heat treatment chamber 111, the measuring point of the outer temperature measuring unit 40 is located between the heating component 20 and the furnace tube 10, and the measuring point of the intermediate temperature measuring unit 50 is located radially in the furnace tube 10 between the measuring points of the inner temperature measuring unit 30 and the outer temperature measuring unit 40.

[0034] It should be noted that the structure and shape of the internal temperature measuring unit 30, the external temperature measuring unit 40, and the intermediate temperature measuring unit 50 can be arbitrary. Figure 1 The image only shows the locations of the temperature measurement points of the internal temperature measurement unit 30, the external temperature measurement unit 40, and the intermediate temperature measurement unit 50.

[0035] The temperature measuring unit can be, for example, a thermocouple. Specifically, the internal temperature measuring unit 30 can be a type S thermocouple, while the external and intermediate thermocouples can be type K thermocouples. Type S thermocouples exhibit good linearity and low drift in the high-temperature range (e.g., 800℃~1200℃), making them suitable for high-precision temperature measurement within the heat treatment cavity 111. Type K thermocouples are low-cost and highly stable, making them suitable for non-core temperature measurement scenarios outside the heat treatment cavity 111. Furthermore, the thermocouple types of the internal temperature measuring unit 30, intermediate temperature measuring unit 50, and external temperature measuring unit 40 can be adjusted as needed, or other elements or temperature probes capable of acquiring temperature values ​​can be used.

[0036] According to the heat treatment apparatus 100 provided in the embodiments of this application, since the heating component 20 is disposed outside the furnace tube 10 and emits thermal radiation toward the heat treatment chamber 111 to provide heat to the heat treatment chamber 111, a temperature gradient with gradually decreasing temperature from the outside to the inside is formed in the radial direction of the furnace tube 10. That is, under normal operating conditions, there is a stable gradient correlation between the temperature values ​​fed back by the inner temperature measuring unit 30, the intermediate temperature measuring unit 50 and the outer temperature measuring unit 40. By arranging the intermediate temperature measuring unit 50 radially between the inner temperature measuring unit 30 and the outer temperature measuring unit 40 along the furnace tube 10, the temperature gradient can be used as a reference to infer whether the inner temperature measuring unit 30 or the outer temperature measuring unit 40 has malfunctioned. This is achieved by determining whether the temperature difference between the inner temperature measuring unit 30 and the intermediate temperature measuring unit 50, and the temperature difference between the outer temperature measuring unit 40 and the intermediate temperature measuring unit 50, deviates from the normal temperature gradient. This ensures the stability of the heat treatment device 100 during operation and guarantees its reliability.

[0037] In some embodiments, the heat treatment apparatus 100 further includes a controller 60. The controller 60 is configured to: acquire temperature values ​​fed back by the internal temperature measuring unit 30, the external temperature measuring unit 40, and the intermediate temperature measuring unit 50; calculate a first difference between the temperature values ​​fed back by the internal temperature measuring unit 30 and the intermediate temperature measuring unit 50; calculate a second difference between the temperature values ​​fed back by the external temperature measuring unit 40 and the intermediate temperature measuring unit 50; and compare the first difference and the second difference with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measuring unit 30 and the external temperature measuring unit 40 are abnormal, wherein the first preset interval is a predetermined range of differences between the internal temperature measuring unit 30 and the intermediate temperature measuring unit 50 when the internal temperature measuring unit 30 is working normally, and the second preset interval is a predetermined range of differences between the external temperature measuring unit 40 and the intermediate temperature measuring unit 50 when the external temperature measuring unit 40 is working normally.

[0038] The first and second preset intervals can be determined, for example, through prior testing. For instance, when both the internal temperature measuring unit 30 and the external temperature measuring unit 40 are working normally, normal operating conditions can be simulated in a prior test to collect the difference range between the internal temperature measuring unit 30 and the intermediate temperature measuring unit 50, and the difference range between the external temperature measuring unit 40 and the intermediate temperature measuring unit 50.

[0039] Since the first preset interval and the second preset interval already meet the normal temperature gradient, by comparing the first difference and the second difference with the first preset interval and the second preset interval respectively, it can be determined whether the first difference and the second difference deviate from the normal temperature gradient, thereby determining whether the internal temperature measuring unit 30 and the external temperature measuring unit 40 have malfunctioned.

[0040] In some embodiments, the heating assembly 20 includes a plurality of heating sections 21 arranged along the axial direction of the furnace tube 10, and the power of each heating section 21 can be independently adjusted. The heat treatment apparatus 100 includes a plurality of internal temperature measuring units 30, a plurality of external temperature measuring units 40, and a plurality of intermediate temperature measuring units 50. The plurality of internal temperature measuring units 30, the plurality of external temperature measuring units 40, and the plurality of intermediate temperature measuring units 50 are all aligned one-to-one with the plurality of heating sections 21 along the axial direction of the furnace tube 10. By sequentially arranging a plurality of independently adjustable heating sections 21, a plurality of internal temperature measuring units 30, a plurality of external temperature measuring units 40, and a plurality of intermediate temperature measuring units 50 along the axial direction of the furnace tube 10, a plurality of independent temperature control zones can be sequentially formed along the axial direction of the furnace tube 10, so as to independently control the locations of axial temperature field non-uniformity and ensure the uniformity of the axial temperature field.

[0041] For example, such as Figure 2As shown, the heating assembly 20 includes six heating sections 21 arranged along the axial direction of the furnace tube 10. Correspondingly, there are six internal temperature measuring units 30, six external temperature measuring units 40, and six intermediate temperature measuring units 50. Thus, the heat treatment apparatus 100 forms six independent temperature control zones along the axial direction of the furnace tube 10.

[0042] For example, refer to Figure 3 Multiple internal temperature measuring units 30 can be housed within a single sleeve 80 and connected to a controller 60 via wires 90 to feed back the collected temperature values ​​to the controller 60. The sleeve 80 can be a TC sleeve, and the wires 90 can be high-temperature resistant wires to protect the internal temperature measuring units 30. Furthermore, multiple intermediate temperature measuring units 50 and multiple external temperature measuring units 40 can also be configured in this way.

[0043] For example, when the two ends of the furnace tube 10 along the axial direction are respectively configured as the air inlet and exhaust ends, the temperature field near the air inlet and exhaust ends may be more easily disturbed. Therefore, the temperature control zones located at the two ends can be configured as auxiliary temperature control zones. That is, the auxiliary temperature control zones are not used for heat treatment of the silicon wafer, but rather serve as temperature field transition zones.

[0044] In some embodiments, the furnace tube 10 includes an inner tube 11 and an outer tube 12 coaxially nested. The heat treatment chamber 111 is formed by the inner wall of the inner tube 11. An annular interlayer space 13 exists between the inner tube 11 and the outer tube 12, and a plurality of intermediate temperature measuring units 50 are disposed within the annular interlayer space 13. The annular interlayer space 13 is either a vacuum or filled with an inert gas.

[0045] The annular interlayer space 13 not only provides space for the intermediate temperature measuring unit 50, but also helps to improve the strength of the furnace tube 10 and extend its lifespan. For example, during heat treatment, such as... Figure 4 As shown, byproducts generated within the heat treatment chamber 111 deposit and accumulate on the inner wall of the inner tube 11, forming a byproduct adhesion layer 112. When there is a difference in the coefficient of thermal expansion between the byproduct adhesion layer 112 and the furnace tube 10, cumulative fatigue stress will occur in the inner tube 11 during repeated heating and cooling cycles, eventually leading to cracking or breakage of the inner tube 11. By setting the annular interlayer space 13 to a vacuum or filling it with inert gas, the cumulative fatigue stress on the inner tube 11 can be reduced, thereby extending the service life of the furnace tube 10.

[0046] Furthermore, when the heating assembly 20 is composed of resistance wires surrounding the furnace tube 10, by setting the furnace tube 10 to a double-layer structure, fragments of the inner tube 11 can be prevented from falling into the gaps of the resistance wires after the inner tube 11 breaks, thereby ensuring the reliability of the heat treatment apparatus 100.

[0047] For example, the inner diameter D1 of the inner tube 11 can be 300mm~500mm, its wall thickness can be 3mm~5mm, and its axial length L can be 4mm~5mm. The width d of the annular interlayer space 13 in the radial direction of the furnace tube 10 can be 50mm~80mm. The inner diameter D2 of the outer tube 12 is D1+2d, its wall thickness can be 4mm~6mm, and its axial length can be the same as that of the inner tube 11.

[0048] In addition, the dimensions of the inner tube 11 and the outer tube 12 can be adjusted according to the size of the silicon wafer to fit the size of the silicon wafer.

[0049] For example, when the annular interlayer space 13 is a vacuum, its vacuum level can be below 10⁻² Pa. When the annular interlayer space 13 is filled with an inert gas, the inert gas is, for example, N2.

[0050] In some embodiments, the heat treatment apparatus 100 further includes a preheating component 70, which is configured to preheat the reactant gas or inert gas before introducing it into the heat treatment chamber 111. By providing the preheating component 70, the reactant gas or inert gas can be preheated before being introduced into the heat treatment chamber 111, thereby avoiding the reaction gas or inert gas from being too cold and affecting the uniformity of the temperature field within the heat treatment chamber 111, and also preventing the furnace tube 10 from being subjected to thermal shock, thus extending the service life of the furnace tube 10. In addition, when there are local cold spots in the temperature field within the heat treatment chamber 111, that is, when the temperature is low at a certain local location within the heat treatment chamber 111, preheating the reactant gas or inert gas by the preheating component 70 before introducing it into the heat treatment chamber 111 can create convection within the heat treatment chamber 111 to eliminate the local cold spots.

[0051] In other embodiments, the preheating component 70 may also be configured to preheat an inert gas before introducing it into the annular interlayer space 13.

[0052] For example, the preheating assembly 70 may include an electrically heated sleeve with a spiral heating channel inside. The reactant gas and the inert gas are heated as they flow through the spiral heating channel inside the electrically heated sleeve.

[0053] In some embodiments, the furnace tube 10 is provided with an exhaust valve 14 communicating with the heat treatment chamber 111. After the heat treatment process is completed, the heating assembly 20 needs to be turned off, and the exhaust valve 14 needs to be opened to discharge the high-temperature gas in the heat treatment chamber 111 for cooling. By adjusting the opening degree of the exhaust valve 14, the rate of temperature decrease of the temperature value fed back by the internal temperature measurement unit 30 can be kept within a suitable range, such as 5°C / min to 10°C / min, thereby avoiding thermal stress on the silicon wafer due to sudden cooling during the cooling process.

[0054] This application embodiment also provides a control method for the above-described heat treatment apparatus 100, wherein the execution subject of the control method may be a controller 60.

[0055] like Figure 5 As shown, the control method may include the following steps: S510, acquiring the temperature values ​​fed back by the internal temperature measuring unit, the external temperature measuring unit, and the intermediate temperature measuring unit; S520, calculating a first difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; S530, calculating a second difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; S540, comparing the first difference and the second difference with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measuring unit and the external temperature measuring unit are abnormal, wherein the first preset interval is a predetermined range of differences between the temperature values ​​fed back by the internal temperature measuring unit and the temperature values ​​fed back by the intermediate temperature measuring unit when the internal temperature measuring unit is working normally, and the second preset interval is a predetermined range of differences between the temperature values ​​fed back by the external temperature measuring unit and the temperature values ​​fed back by the intermediate temperature measuring unit when the external temperature measuring unit is working normally.

[0056] According to the control method for a heat treatment apparatus provided in this application embodiment, since the heating component is located outside the furnace tube and emits thermal radiation towards the heat treatment chamber to provide heat to the heat treatment chamber, a temperature gradient with gradually decreasing temperature from the outside to the inside is formed in the radial direction of the furnace tube. That is, under normal operating conditions, there is a stable gradient correlation between the temperature values ​​fed back by the inner temperature measuring unit, the intermediate temperature measuring unit, and the outer temperature measuring unit. By setting the intermediate temperature measuring unit radially between the inner and outer temperature measuring units, based on the temperature gradient and using the temperature value fed back by the intermediate temperature measuring unit as a reference, it is possible to infer whether the inner or outer temperature measuring unit has malfunctioned by determining whether the difference between the temperature value fed back by the inner and intermediate temperature measuring units, and the difference between the temperature value fed back by the outer and intermediate temperature measuring units, deviates from the normal temperature gradient. This ensures the stability of the heat treatment apparatus during operation and guarantees the reliability of the heat treatment apparatus.

[0057] In some embodiments, step S540 may include: determining whether a first difference and a second difference are respectively located within a first preset range and a second preset range; if the first difference is not located within the first preset range but the second difference is located within the second preset range, then it is determined that the temperature value fed back by the internal temperature measuring unit is abnormal while the temperature value fed back by the external temperature measuring unit is normal; if the first difference is located within the first preset range but the second difference is not located within the second preset range, then it is determined that the temperature value fed back by the internal temperature measuring unit is normal while the temperature value fed back by the external temperature measuring unit is abnormal.

[0058] In some embodiments, the first difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit, and the second difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit. The first preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit when the internal temperature measurement unit is working normally. The second preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit when the external temperature measurement unit is working normally. When the temperature value fed back by the internal temperature measuring unit is determined to be abnormal while the temperature value fed back by the external temperature measuring unit is normal, the control method further includes: comparing a first difference with the upper and lower limits of a first preset interval respectively; when the first difference is lower than the lower limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is lower than the actual temperature value at the internal temperature measuring unit; when the first difference is higher than the upper limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is higher than the actual temperature value at the internal temperature measuring unit; and / or, when the temperature value fed back by the internal temperature measuring unit is determined to be normal while the temperature value fed back by the external temperature measuring unit is abnormal, the control method further includes: comparing a second difference with the upper and lower limits of a second preset interval respectively; when the second difference is lower than the lower limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is lower than the actual temperature value at the external temperature measuring unit; when the second difference is higher than the upper limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is higher than the actual temperature value at the external temperature measuring unit.

[0059] It should be noted that the first difference can also be obtained by subtracting the temperature value fed back by the internal temperature measuring unit from the temperature value fed back by the intermediate temperature measuring unit. Correspondingly, the first preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measuring unit from the temperature value fed back by the internal temperature measuring unit when the internal temperature measuring unit is operating normally. Furthermore, when the first difference is compared with the upper and lower limits of the first preset interval, the determination result will also change accordingly. The specific determination process follows the same logic and will not be elaborated here.

[0060] For example, the first preset range is -25℃ to -10℃, and the second preset range is 25℃ to 35℃. The temperature value reported by the internal temperature measuring unit is 25℃, the temperature value reported by the external temperature measuring unit is 850℃, and the temperature value reported by the intermediate temperature measuring unit is 820℃. The first temperature difference is -795℃, and the second temperature difference is 30℃. In this case, since the first temperature difference is not within the first preset range while the second temperature difference is within the second preset range, it can be determined that the temperature value reported by the internal temperature measuring unit is abnormal, while the temperature value reported by the external temperature measuring unit is normal. That is, the internal temperature measuring unit has malfunctioned. Since the first temperature difference of -795℃ is lower than the lower limit of the first preset range of -25℃, it can be determined that the temperature value reported by the internal temperature measuring unit is lower than the actual temperature value at the internal temperature measuring unit.

[0061] In some embodiments, the damage mode of the internal and external temperature measuring units can be further determined based on the temperature values ​​fed back by the internal and external temperature measuring units.

[0062] For example, when the temperature value fed back by the internal temperature measuring unit is room temperature or remains at a lower temperature value, the failure mode of the internal temperature measuring unit is determined to be open circuit; when the temperature value fed back by the internal temperature measuring unit is too high or remains at a higher temperature value, the failure mode of the internal temperature measuring unit is determined to be short circuit; when the temperature value fed back by the internal temperature measuring unit changes lagging or drifts, the failure mode of the internal temperature measuring unit is determined to be decreased sensitivity.

[0063] For example, when the temperature value fed back by the external temperature measuring unit is room temperature or remains at a low temperature, the failure mode of the external temperature measuring unit is determined to be open circuit; when the temperature value fed back by the external temperature measuring unit is too high (e.g., 1000°C) or remains at a high temperature, the failure mode of the external temperature measuring unit is determined to be short circuit; when the temperature value fed back by the external temperature measuring unit cannot change with the power of the heating component, the failure mode of the external temperature measuring unit is determined to be thermal response failure.

[0064] In some embodiments, step S540 may further include: if the first difference is not within the first preset range and the second difference is not within the second preset range, then determine whether the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the external temperature measuring unit are abnormal based on the operating status parameters of the heat treatment device, wherein the operating status parameters of the heat treatment device include at least one of the power of the heating component and the uniformity of the process result of the product.

[0065] In some embodiments, the abnormality of the temperature values ​​fed back by the internal temperature measuring unit and the external temperature measuring unit can be determined based on the degree to which the first temperature difference deviates from the first preset range and the degree to which the second temperature difference deviates from the second preset range.

[0066] For example, the first preset range is -25℃ to -10℃, and the second preset range is 25℃ to 35℃. The temperature value reported by the internal temperature measuring unit is 830℃, the temperature value reported by the external temperature measuring unit is 1000℃, and the temperature value reported by the intermediate temperature measuring unit is 880℃. The first temperature difference is -50℃, and the second temperature difference is 120℃. Although the first temperature difference is not within the first preset range and the second temperature difference is not within the second preset range, the first temperature difference is only 25℃ lower than the lower limit of the first preset range, i.e., it does not deviate significantly from the first preset range. However, the second temperature difference exceeds the upper limit of the second preset range by 85℃, i.e., it deviates significantly from the second preset range. At this time, it can be determined that the temperature value reported by the internal temperature measuring unit is normal, while the temperature value reported by the external temperature measuring unit is abnormal. That is, the external temperature measuring unit has malfunctioned, causing the heat treatment device to continuously output excessively high power to control the heating component, thereby causing the temperatures reported by both the internal and intermediate temperature measuring units to rise abnormally.

[0067] In some embodiments, when the heating assembly includes multiple heating sections arranged axially along the furnace tube, and the power of each heating section is independently adjustable, and the heat treatment apparatus includes multiple internal temperature measuring units, multiple external temperature measuring units, and multiple intermediate temperature measuring units, with each of the internal, external, and intermediate temperature measuring units corresponding one-to-one with a heating section along the axial direction of the furnace tube, the control method further includes: acquiring temperature values ​​fed back by the multiple internal temperature measuring units; comparing the temperature value fed back by each internal temperature measuring unit with a target temperature value; if the temperature value fed back by the internal temperature measuring unit is lower than the target temperature value, increasing the power of the heating section corresponding to the internal temperature measuring unit; and if the temperature value fed back by the internal temperature measuring unit is higher than the target temperature value, decreasing the power of the heating section corresponding to the internal temperature measuring unit. By monitoring the axial temperature field through multiple internal temperature measuring units arranged sequentially along the axial direction of the furnace tube and controlling the temperature through the corresponding heating sections, the uniformity of the axial temperature field can be ensured.

[0068] In some embodiments, when the heat treatment apparatus further includes a preheating component configured to preheat the reactant gas or inert gas before introducing it into the heat treatment chamber, the control method further includes: comparing the temperature values ​​fed back by each of the plurality of internal temperature measuring units; if the difference between the temperature values ​​fed back by any two internal temperature measuring units is greater than 3°C, then controlling the preheating component to preheat the reactant gas or inert gas to a target temperature range before introducing it into the heat treatment chamber, wherein the upper limit of the target temperature range is the target temperature value + 5°C, and the lower limit of the target temperature range is the target temperature value - 5°C. By preheating the reactant gas or inert gas before introducing it into the heat treatment chamber using the preheating component, the uniformity of the temperature field within the heat treatment chamber can be avoided due to the low temperature of the introduced reactant gas or inert gas. Furthermore, when there are local cold spots in the temperature field within the heat treatment chamber, i.e., when the temperature at a certain local location within the heat treatment chamber is low, preheating the reactant gas or inert gas before introducing it into the heat treatment chamber using the preheating component can create convection within the heat treatment chamber to eliminate these local cold spots.

[0069] In some embodiments, the control method further includes: acquiring the temperature value fed back by the external temperature measurement unit during the process of the temperature inside the heat treatment chamber rising from room temperature to the target temperature value, and adjusting the power of the heating component based on a PID control algorithm until the temperature inside the heat treatment chamber rises to 90% of the target temperature. Adjusting the power of the heating component by using a PID control algorithm can prevent the furnace tube from being damaged by thermal shock during the heating process.

[0070] In some embodiments, when an exhaust valve communicating with the heat treatment chamber is provided on the furnace tube, the control method further includes: during the process of the temperature in the heat treatment chamber decreasing from a target temperature value to room temperature, acquiring the temperature value fed back by the internal temperature measurement unit and calculating the rate of decrease of the temperature value fed back by the internal temperature measurement unit, and adjusting the opening of the exhaust valve so that the rate of decrease of the temperature value fed back by the internal temperature measurement unit is 5℃ / min to 10℃ / min. By controlling the rate of decrease of the temperature value fed back by the internal temperature measurement unit to 5℃ / min to 10℃ / min, thermal stress caused by rapid cooling of the silicon wafer can be avoided during the cooling process.

[0071] In the embodiments of this application, unless otherwise specified, the connection can be a detachable connection using bolts, nuts, screws, clips, magnets, etc. In some connections where there is no particular requirement for a detachable fit, a non-detachable connection can be achieved through welding, bonding, etc.

[0072] The terms "an embodiment" or "embodiment" used in this specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Additionally, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0073] It should be understood that the terms “on,” “above,” and “on top of” in this application should be interpreted in the broadest possible way, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on top of something” but also “on top of something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0074] Furthermore, for ease of explanation, spatial relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of a component or feature relative to other components or features as shown in the figures. Spatial relative terms are intended to encompass different orientations of components in use or operation other than those shown in the figures. Devices may have other orientations (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein may be interpreted accordingly.

[0075] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0076] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A heat treatment apparatus, characterized in that, include: Furnace tube, wherein a heat treatment cavity is formed inside the furnace tube; A heating element is disposed outside the furnace tube and is configured to emit thermal radiation toward the heat treatment chamber to provide heat to the heat treatment chamber. An internal temperature measurement unit is located inside the heat treatment cavity; An external temperature measurement unit is located between the heating assembly and the furnace tube; An intermediate temperature measuring unit is located radially on the furnace tube, between the inner temperature measuring unit and the outer temperature measuring unit.

2. The heat treatment apparatus as described in claim 1, characterized in that, It also includes a controller, which is configured to: Obtain the temperature values ​​fed back by the internal temperature measuring unit, the external temperature measuring unit, and the intermediate temperature measuring unit; Calculate the first difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; Calculate the second difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; The first difference and the second difference are compared with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measurement unit and the temperature values ​​fed back by the external temperature measurement unit are abnormal. Wherein, the first preset interval is a predetermined range of difference between the internal temperature measuring unit and the intermediate temperature measuring unit when the internal temperature measuring unit is working normally, and the second preset interval is a predetermined range of difference between the external temperature measuring unit and the intermediate temperature measuring unit when the external temperature measuring unit is working normally.

3. The heat treatment apparatus as described in claim 1, characterized in that, The heating assembly includes multiple heating sections arranged along the axial direction of the furnace tube, and the power of each heating section can be independently adjusted. The heat treatment device includes multiple internal temperature measuring units, multiple external temperature measuring units, and multiple intermediate temperature measuring units. Each of the multiple internal temperature measuring units, multiple external temperature measuring units, and multiple intermediate temperature measuring units corresponds one-to-one with the multiple heating parts along the axial direction of the furnace tube.

4. The heat treatment apparatus as described in claim 1, characterized in that, The furnace tube includes an inner tube and an outer tube that are coaxially nested. The heat treatment chamber is formed by the inner wall of the inner tube. There is an annular interlayer space between the inner tube and the outer tube. The plurality of intermediate temperature measuring units are arranged in the annular interlayer space. The annular interlayer space is a vacuum or filled with inert gas. And / or, The heat treatment apparatus further includes a preheating component, which is configured to preheat the reaction gas or inert gas before introducing it into the heat treatment chamber; And / or, The furnace tube is equipped with an exhaust valve that connects to the heat treatment chamber.

5. A control method for a heat treatment apparatus, characterized in that, Applied to a heat treatment apparatus, wherein the heat treatment apparatus includes: Furnace tube, wherein a heat treatment cavity is formed inside the furnace tube; A heating assembly is coaxially sleeved outside the furnace tube and spaced apart from the furnace tube. The heating assembly is configured to emit thermal radiation toward the heat treatment chamber to provide heat to the heat treatment chamber. An internal temperature measurement unit is located inside the heat treatment cavity; An external temperature measurement unit is located between the heating assembly and the furnace tube; An intermediate temperature measuring unit is located radially from the furnace tube, between the inner temperature measuring unit and the outer temperature measuring unit. The control method for the heat treatment apparatus includes: Obtain the temperature values ​​fed back by the internal temperature measuring unit, the external temperature measuring unit, and the intermediate temperature measuring unit; Calculate the first difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; Calculate the second difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit; The first difference and the second difference are compared with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measurement unit and the temperature values ​​fed back by the external temperature measurement unit are abnormal. Wherein, the first preset interval is a predetermined range of difference between the temperature value fed back by the internal temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit when the internal temperature measuring unit is working normally, and the second preset interval is a predetermined range of difference between the temperature value fed back by the external temperature measuring unit and the temperature value fed back by the intermediate temperature measuring unit when the external temperature measuring unit is working normally.

6. The control method for a heat treatment apparatus as described in claim 5, characterized in that, The first difference and the second difference are compared with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measurement unit and the temperature values ​​fed back by the external temperature measurement unit are abnormal, including: Determine whether the first difference and the second difference are located within the first preset interval and the second preset interval, respectively; If the first difference is not within the first preset range while the second difference is within the second preset range, then it is determined that the temperature value fed back by the internal temperature measurement unit is abnormal while the temperature value fed back by the external temperature measurement unit is normal. If the first difference is within the first preset range and the second difference is not within the second preset range, then it is determined that the temperature value fed back by the internal temperature measurement unit is normal and the temperature value fed back by the external temperature measurement unit is abnormal.

7. The control method for a heat treatment apparatus as described in claim 6, characterized in that, The first difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit. The second difference is obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit. The first preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the internal temperature measurement unit when the internal temperature measurement unit is working normally. The second preset interval is a predetermined range of differences obtained by subtracting the temperature value fed back by the intermediate temperature measurement unit from the temperature value fed back by the external temperature measurement unit when the external temperature measurement unit is working normally. When it is determined that the temperature value fed back by the internal temperature measuring unit is abnormal while the temperature value fed back by the external temperature measuring unit is normal, the control method further includes: comparing the first difference with the upper limit and lower limit of the first preset interval respectively; when the first difference is lower than the lower limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is lower than the actual temperature value at the internal temperature measuring unit; when the first difference is higher than the upper limit of the first preset interval, determining that the temperature value fed back by the internal temperature measuring unit is higher than the actual temperature value at the internal temperature measuring unit. And / or, When it is determined that the temperature value fed back by the internal temperature measuring unit is normal while the temperature value fed back by the external temperature measuring unit is abnormal, the control method further includes: comparing the second difference with the upper limit and lower limit of the second preset interval respectively; when the second difference is lower than the lower limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is lower than the actual temperature value at the external temperature measuring unit; when the second difference is higher than the upper limit of the second preset interval, determining that the temperature value fed back by the external temperature measuring unit is higher than the actual temperature value at the external temperature measuring unit.

8. The control method for a heat treatment apparatus as described in claim 5, characterized in that, The method further includes comparing the first difference and the second difference with a first preset interval and a second preset interval, respectively, to determine whether the temperature values ​​fed back by the internal temperature measurement unit and the temperature values ​​fed back by the external temperature measurement unit are abnormal. If the first difference is not within the first preset range and the second difference is not within the second preset range, then based on the operating status parameters of the heat treatment device, it is determined whether the temperature values ​​fed back by the internal temperature measurement unit and the temperature values ​​fed back by the external temperature measurement unit are abnormal. The operating parameters of the heat treatment device include at least one of the power of the heating component and the uniformity of the product's process results.

9. The control method for a heat treatment apparatus as described in claim 5, characterized in that, When the heating assembly includes multiple heating sections arranged axially along the furnace tube, and the power of each heating section can be independently adjusted, and the heat treatment device includes multiple internal temperature measuring units, multiple external temperature measuring units, and multiple intermediate temperature measuring units, wherein each of the multiple internal temperature measuring units, multiple external temperature measuring units, and multiple intermediate temperature measuring units corresponds one-to-one with the multiple heating sections along the axial direction of the furnace tube, the control method further includes: Obtain the temperature values ​​fed back by the multiple internal temperature measurement units; The temperature value fed back by each of the plurality of internal temperature measurement units is compared with the target temperature value; If the temperature value fed back by the internal temperature measuring unit is lower than the target temperature value, the power of the heating unit corresponding to the internal temperature measuring unit is increased; If the temperature value fed back by the internal temperature measuring unit is higher than the target temperature value, the power of the heating element corresponding to the internal temperature measuring unit is reduced.

10. The control method for a heat treatment apparatus as described in claim 5, characterized in that, When the heat treatment apparatus further includes a preheating component configured to preheat the reaction gas or inert gas before introducing it into the heat treatment chamber, the control method further includes: The temperature values ​​fed back by each of the plurality of internal temperature measurement units are compared with each other; If the temperature difference between any two internal temperature measuring units is greater than 3°C, then the preheating component is controlled to preheat the reaction gas or inert gas to the target temperature range before introducing it into the heat treatment chamber. The upper limit of the target temperature range is the target temperature value + 5℃, and the lower limit of the target temperature range is the target temperature value - 5℃.

11. The control method for a heat treatment apparatus as described in claim 5, characterized in that, The control method further includes: During the process of the temperature in the heat treatment chamber rising from room temperature to the target temperature, the temperature value fed back by the external temperature measurement unit is acquired, and the power of the heating component is adjusted based on the PID control algorithm until the temperature in the heat treatment chamber rises to 90% of the target temperature.

12. The control method for a heat treatment apparatus as described in claim 5, characterized in that, When the furnace tube is equipped with an exhaust valve that connects to the heat treatment chamber, the control method further includes: During the process of the temperature in the heat treatment chamber decreasing from the target temperature value to room temperature, the temperature value fed back by the internal temperature measuring unit is acquired and the rate of decrease of the temperature value fed back by the internal temperature measuring unit is calculated. The opening of the exhaust valve is adjusted so that the rate of decrease of the temperature value fed back by the internal temperature measuring unit is 5℃ / min~10℃ / min.

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