Silicon ingot preparation method, silicon ingot preparation device and preparation system with silicon ingot preparation device

Abstract

The invention discloses a silicon ingot preparation method, a silicon ingot preparation device and a preparation system with the silicon ingot preparation device. The silicon ingot preparation method comprises the following steps: adjusting the pressure of a reaction chamber to be lower than atmospheric pressure; heating the reaction cavity to a preset temperature through a temperature regulation and control unit; introducing a silicon source gas and a carrier gas into the reaction cavity, and carrying out heat preservation for a preset time at the preset temperature; raising the temperature of the reaction cavity to decompose the silicon source gas; and locally cooling the reaction cavity where the bearing platform is located so as to deposit the silicon ingot on the bearing platform. According to the method for directly preparing the silicon ingot through vapor deposition, a plurality of links such as industrial silicon smelting, chemical purification and ingot casting in a traditional process are avoided, and the preparation period is greatly shortened; and the technological process is obviously simplified.

Description

Technical Field

[0001] The present invention belongs to the field of chemical industry and relates to a silicon ingot preparation method, a silicon ingot preparation device and a preparation system having the same. Background Art

[0002] Polysilicon is a critical raw material for the solar photovoltaic industry, and its production quality and cost directly impact its development. Currently, the mainstream production processes for solar-grade polysilicon include the modified Siemens process and the silane fluidized bed process. The modified Siemens process involves synthesizing chlorosilane from industrial silicon powder (purity >98%) and hydrochloric acid. This is then purified through distillation to produce high-purity trichlorosilane, which is then reduced to polysilicon. The silane fluidized bed process, on the other hand, involves passing silane gas through a fluidized bed reactor containing silicon powder seed crystals for thermal decomposition to produce polysilicon.

[0003] However, existing polysilicon production methods suffer from lengthy processes and high energy consumption. Specifically, the traditional process requires a series of steps, including industrial silicon smelting, chemical purification, polysilicon production, and subsequent ingot casting or crystal pulling. This is not only complex, but the integration of these steps also increases production costs and time. Furthermore, existing production equipment often lacks precise temperature control and position adjustment mechanisms, making it difficult to ensure stable and consistent product quality.

[0004] Therefore, how to simplify the process, improve preparation efficiency and reduce energy consumption has become a technical problem that needs to be solved urgently in this field. Summary of the Invention

[0005] To address one of the aforementioned issues, the present invention provides a method, apparatus, and system for preparing silicon ingots. This method directly prepares silicon ingots through vapor deposition, significantly shortening the preparation cycle and significantly simplifying the process flow. The apparatus integrates functional units such as pressure regulation, temperature control, gas management, and position adjustment, and, in conjunction with an automated control system, forms a complete silicon ingot preparation solution.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0007] A method for preparing a silicon ingot comprises the following steps: regulating the pressure of a reaction chamber to be below atmospheric pressure; heating the reaction chamber to a predetermined temperature via a temperature control unit; introducing a silicon source gas and a carrier gas into the reaction chamber and maintaining the temperature at the predetermined temperature for a predetermined time; increasing the temperature of the reaction chamber to decompose the silicon source gas; and locally cooling the reaction chamber where a carrying platform is located to deposit the silicon ingot on the carrying platform.

[0008] In one embodiment, the pressure adjustment includes placing the reaction chamber in a vacuum, wherein the vacuum degree is 10 -3 Pa and below.

[0009] In one embodiment, the predetermined temperature is 200°C-400°C; and / or, the predetermined time is 0.5h-1h; and / or, the temperature of the reaction chamber is increased to 550°C-900°C, and the silicon source gas decomposes; and / or, the local cooling rate is 1°C / min-10°C / min, and the temperature is reduced to 400°C-550°C.

[0010] In one embodiment, the silicon source gas includes at least one of trichlorosilane, silicon tetrachloride, and silane gas.

[0011] In one embodiment, during the process of depositing and forming the silicon ingot, the height of the top of the carrying platform is lowered by a position adjustment mechanism.

[0012] In one embodiment, after the silicon ingot is deposited, hydrogen or an inert gas is introduced into the reaction chamber to exhaust unreacted silicon source gas and / or by-product gas.

[0013] A silicon ingot preparation device comprises: a furnace body structure for providing a reaction chamber; a gas inlet for introducing silicon source gas and carrier gas into the reaction chamber; a temperature control unit cooperating with the furnace body structure to adjust the temperature of the reaction chamber; a pressure regulating unit for evacuating or introducing gas into the furnace body structure; a carrying platform unit comprising a carrying platform and a position adjustment mechanism for changing the relative position between the carrying platform and the furnace body structure during the silicon ingot deposition process; and an exhaust port for discharging unreacted silicon source gas or by-product gas.

[0014] In one embodiment, the temperature control unit is selected from an induction heating component, a resistance heating unit, or a microwave heating system; and / or, the temperature control unit includes a gas source heating device arranged at the gas inlet, and a furnace cavity heating device arranged around at least part of the reaction cavity; and / or, the furnace body structure has at least two temperature control zones inside, and at least two temperature control zones are arranged along the height direction of the reaction cavity, and the supporting platform is located in any one of the second and following temperature control zones from the top to the bottom.

[0015] In one embodiment, the furnace structure has at least two temperature control zones inside, and the at least two temperature control zones are arranged along the height direction of the reaction chamber, and the supporting platform is located in any one of the second and following temperature control zones from the top to the bottom.

[0016] A silicon ingot preparation system comprises: the silicon ingot preparation device described above; an automation control module for controlling the temperature control unit, position adjustment mechanism and pressure management unit; and a gas source delivery mechanism for providing silicon source gas and carrier gas and introducing them into the reaction chamber.

[0017] Compared with the existing technology, the beneficial effects of the present invention are: the present invention adopts the method of directly preparing silicon ingots by vapor deposition, avoiding multiple links such as industrial silicon smelting, chemical purification, and ingot casting in traditional processes, greatly shortening the preparation cycle; and significantly simplifying the process flow.

[0018] The present invention also reduces energy loss in intermediate links and improves production efficiency through optimized process parameter control and integrated equipment design.

[0019] The present invention also adopts multi-zone temperature control and dynamic adjustment technology to achieve precise control of the silicon ingot growth process, improve the uniformity and stability of the product, and improve product quality.

[0020] The present invention also reduces human operation errors through the integration of automatic control modules, improves the controllability of the production process and the product yield, and realizes intelligent manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 1 is a schematic structural diagram of a silicon ingot preparation apparatus according to an embodiment of the present invention;

[0022] Figure 2 It is a flow chart of a method for preparing a silicon ingot according to one embodiment of the present invention.

[0023] Among them, 1-furnace structure, 10-reaction chamber, 2-gas inlet, 31-gas source heating device, 32-furnace chamber heating device, 33-temperature measuring device, 41-carrying platform, 42-position adjustment mechanism, 5-exhaust port, DETAILED DESCRIPTION

[0024] The following is a further introduction to the technical solution of the present invention in conjunction with the accompanying drawings and specific implementation methods. Figures 1-2 The preferred embodiments of the present invention are shown in the figures. However, it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by those skilled in the art based on these embodiments fall within the scope of protection of the present invention.

[0025] The words used in this invention to express positions and directions, such as "top" and "bottom", are all used as references when using the silicon ingot preparation device. Furthermore, the drawings in this invention are all in a very simplified form and are not in exact proportions. They are only used to facilitate and clearly illustrate the various embodiments of the invention.

[0026] In one embodiment of the present invention, a method for preparing a silicon ingot is provided, comprising the following steps: regulating the pressure of a reaction chamber 10 to be lower than atmospheric pressure; heating the reaction chamber 10 to a predetermined temperature through a temperature control unit; introducing a silicon source gas and a carrier gas into the reaction chamber 10, and maintaining the temperature at the predetermined temperature for a predetermined time; increasing the temperature of the reaction chamber 10 to decompose the silicon source gas; and locally cooling the reaction chamber 10 where a carrying platform 41 is located to deposit a silicon ingot on the carrying platform 41.

[0027] In one embodiment of the present invention, the pressure regulation includes placing the reaction chamber 10 in a vacuum. During implementation, the reaction chamber 10 is preferably evacuated or maintained at a pressure below atmospheric pressure using a vacuum pump or a corresponding negative pressure system to effectively expel other impurity gases and inhibit the incorporation of oxygen and water vapor, thereby ensuring that the silicon source gas undergoes chemical vapor deposition in a purer environment, further improving the purity and crystal quality of the deposited silicon ingot. At the same time, the oxidation reaction during the process and secondary contamination caused by foreign particles entering the reaction chamber 10 can be reduced, making the quality of the produced silicon ingot more stable during subsequent cooling or gas replacement steps, significantly enhancing the preparation efficiency and product stability of the present method.

[0028] In a specific embodiment, the vacuum degree is 10 -3 Pa and below.

[0029] In one embodiment of the present invention, the temperature control unit is selected from an induction heating component, a resistance heating unit, or a microwave heating system.

[0030] In practice, different heating methods can be selected based on actual production line requirements and equipment availability. Induction heating elements typically provide a relatively efficient and uniform temperature field, ensuring stable heating of the silicon source gas during deposition. Resistance heating units, on the other hand, are mature and easy to maintain, making them suitable for precise control of temperature distribution during large-scale production. Microwave heating systems are relatively new, offering rapid temperature increases and minimizing local overheating, thereby reducing excessive decomposition or heat loss to the substrate.

[0031] Through the flexible selection of the above-mentioned multiple temperature control units, continuous and controllable heating, insulation and cooling can be achieved in the same reaction chamber 10, so that the decomposition of the silicon source gas is more thorough and the deposition is more uniform, and the purity and crystallization integrity of the silicon ingot are effectively improved, while taking into account the reduction of energy consumption and equipment modification costs, further enhancing the applicability and stability of the preparation method.

[0032] In one specific embodiment, the predetermined temperature is 200°C-400°C, close to the decomposition temperature of the silicon source gas, thereby improving efficiency. And / or, the predetermined time is 0.5-1 hour, ensuring that the overall temperature of the gas source is uniform and stabilized within the predetermined temperature range. And / or, the temperature of the reaction chamber 10 is raised to 550-900°C to allow the silicon source gas to decompose. And / or, the local cooling rate is 1°C / min-10°C / min, and the temperature is lowered to 400-550°C. Slow cooling can produce silicon ingots with good uniformity and neat crystal phases, while also reducing stress.

[0033] In one embodiment of the present invention, the silicon source gas includes at least one of trichlorosilane, silicon tetrachloride, and silane gas. In practice, these silicon source gases can be flexibly selected individually or in combination based on different production line requirements and process objectives. For example, during the preheating phase of the reaction chamber 10, trichlorosilane or silicon tetrachloride can be introduced with hydrogen or an inert gas, respectively. Alternatively, when rapid deposition is required, silane gas can be used and fully decomposed at an appropriate temperature and pressure. During the deposition process, by adjusting the flow rate and input order of each component, the effective utilization rate of the silicon source and deposition efficiency can be further improved, thereby enhancing the precision of controlling the quality of the silicon ingot.

[0034] The diversification of the silicon source gas helps to balance production capacity, process cost and product purity, and can be combined with the vacuum operation to effectively suppress the mixing of impurities, and ultimately complete the deposition process from gas phase to solid phase in the same reaction chamber 10, thereby enhancing the uniformity and crystal integrity of the silicon ingot, and significantly improving the operability and applicability of this method.

[0035] In one embodiment of the present invention, during the deposition process of the silicon ingot, the height of the top of the supporting platform 41 is lowered by a position adjustment mechanism 42. Specifically, mechanical lifting or other methods can be used to gradually lower the supporting platform 41 during the growth of the silicon ingot, thereby maintaining an appropriate distance between the silicon source gas decomposition zone and the silicon ingot surface, thereby avoiding defects caused by local overheating or uneven gas flow.

[0036] Through the real-time adjustment of the position adjustment mechanism 42, the silicon source gas can be deposited more evenly on the surface of the supporting platform 41 and form a smooth and dense crystal structure; at the same time, maintaining a reasonable temperature difference between the high-temperature zone and the silicon ingot can effectively reduce thermal cracks and stress concentration, improve the overall mechanical strength of the silicon ingot, and achieve the technical effect of efficient preparation and stable growth.

[0037] By combining the aforementioned vacuum environment and multiple silicon sources or carrier gases, this method can complete the continuous vacuum extraction, temperature rise and fall, deposition and cooling steps in the same reaction chamber 10, further ensuring the purity and uniformity of the produced silicon ingot.

[0038] In one embodiment of the present invention, the method further comprises: after the silicon ingot is deposited, introducing hydrogen or an inert gas into the reaction chamber 10 to discharge unreacted silicon source gas and / or by-product gas.

[0039] In this way, hydrogen or inert gas can be used for purging and replacement to effectively discharge residual silicon source gas and by-product gas, reducing secondary contamination or adverse side reactions to the silicon ingot during the cooling process, thereby improving the purity of the final silicon ingot and simplifying subsequent cleaning or processing steps.

[0040] In one specific implementation, residual impurities are removed through vacuuming, allowing the raw materials to undergo chemical vapor deposition in a relatively pure environment. The reaction chamber 10 is then heated to 200-400°C and maintained for a period of time to allow the silicon source gas and carrier gas to fully mix and distribute throughout the reaction zone. The temperature is then raised again to 400-900°C to decompose the silicon source gas. The temperature is then locally lowered at a rate of 1-10°C / min, allowing the gaseous silicon released from the decomposition of the silicon source gas to deposit on the carrier platform 41 to form a silicon ingot, enhancing deposition uniformity and reducing thermal stress.

[0041] Because the above steps are completed continuously within the same reaction chamber 10, the impact of intermediate transfer on the purity of the silicon ingot is avoided, and redundant smelting, purification, and ingot casting processes are reduced, thereby effectively improving production efficiency and reducing energy consumption, thereby obtaining high-purity and uniformly grown silicon ingots. This method can shorten the entire polysilicon production process, reduce production costs, and ensure deposition efficiency. At the same time, the introduction of inert gas or hydrogen at the end of the reaction can further discharge unreacted silicon source gas and byproducts, thereby significantly improving the quality of the silicon ingot.

[0042] Specifically, the silicon source gas includes at least one of trichlorosilane, silicon tetrachloride, and silane gas, and the carrier gas is high-purity hydrogen or an inert gas.

[0043] In one embodiment of the present invention, a silicon ingot preparation device is further provided, including a furnace structure 1 , a gas inlet 2 , a temperature control unit, a pressure adjustment unit, a carrying platform 41 unit, and an exhaust port 5 .

[0044] The furnace structure 1 is used to provide a reaction chamber 10. Specifically, the furnace structure 1 is usually made of a high-temperature resistant alloy or a composite material. The reaction chamber 10 can be regarded as a closed or semi-closed inner cavity structure in the art, which is used to carry out a thermochemical reaction or physical vapor deposition of silicon source gas and carrier gas.

[0045] In one embodiment, the furnace structure 1 includes a heat-insulating wall and a reaction chamber 10 surrounded by the heat-insulating wall. The reaction chamber 10 is in a cylindrical shape extending in an up-down direction.

[0046] In one embodiment of the present invention, the furnace structure 1 has at least two temperature-controlled zones within it, enabling independent or segmented temperature control in different areas. The carrier platform 41 is positioned within any of the second and subsequent temperature-controlled zones from the top. The silicon source gas is cracked in the upper temperature-controlled zone and then cooled and deposited in the lower zone. This results in a well-defined temperature distribution and maximizes energy efficiency.

[0047] In specific applications, the at least two temperature-controlled zones can be arranged according to the height of the furnace structure 1 and along the height of the reaction chamber 10. By separately installing temperature control units such as induction heating components, resistance heating units, or microwave heating systems, and equipping them with corresponding temperature sensors and control circuits, independent heating or cooling of different zones can be achieved. Segmented temperature control can provide higher temperatures in the early stages of silicon ingot deposition to promote crystal nucleation, and gradually reduce or adjust the temperatures of some temperature-controlled zones during the subsequent growth stages to reduce thermal stress and deformation and improve the crystal quality of the silicon ingot.

[0048] Preferably, the temperature distribution can also cooperate with the position adjustment mechanism 42 to maintain a reasonable thermal field gradient for the deposition surface at the supporting platform 41, thereby avoiding crystal defects in the material due to overheating or local temperature unevenness, and taking into account the full decomposition of the silicon source gas and the effective discharge of by-products.

[0049] Through this multi-zone temperature control design, a targeted temperature environment is provided for local areas while maintaining overall process stability, significantly improving the purity and uniformity of silicon ingots and laying a more stable crystal foundation for subsequent slicing, doping or surface treatment processes.

[0050] The gas inlet 2 is used to introduce silicon source gas and carrier gas into the reaction chamber 10. The gas inlet 2 is connected to a silicon source gas or carrier gas storage tank via a pipeline and a flow controller. The silicon source gas, such as silane or chlorosilane, and the carrier gas, such as hydrogen, argon, or nitrogen, enter the reaction chamber 10 at a suitable flow rate and temperature to chemically react or physically deposit on the substrate or growth surface.

[0051] In one embodiment, the gas inlet 2 is connected to the top of the reaction chamber 10 , specifically to the center of the top of the reaction chamber 10 , so that the gas enters the reaction chamber 10 from directly above.

[0052] The temperature control unit cooperates with the furnace structure 1 to adjust the temperature of the reaction chamber 10. The temperature control unit can apply heat to the furnace structure 1 through an induction heating assembly, a resistance heating unit, or a microwave heating system, and perform feedback monitoring through a temperature measuring device 33 such as a thermocouple or an optical thermometer to ensure that a suitable temperature distribution is maintained during the silicon ingot formation process.

[0053] Specifically, the temperature control unit includes a gas source heating device 31 provided at the gas inlet 2 to heat the gas entering the reaction chamber 10 to prevent the temperature difference between the gas and the reaction chamber 10 from being too large, thereby affecting the temperature field distribution in the reaction chamber 10 after the gas enters.

[0054] The temperature control unit further includes a furnace chamber heating device 32 disposed around at least a portion of the reaction chamber 10 to provide the reaction chamber 10 with a temperature required for forming a silicon ingot.

[0055] Both the gas source heating device 31 and the furnace cavity heating device 32 can selectively employ induction heating components, resistance heating units, or microwave heating systems. In one embodiment, the gas source heating device 31 is a resistance heating unit disposed around the gas inlet 2. In one embodiment, the furnace cavity heating device 32 is an induction heating component that extends circumferentially around the reaction chamber 10 to ensure uniform temperature distribution, stable silicon ingot growth, and further reduce energy consumption.

[0056] The pressure regulating unit is used to evacuate or introduce gas into the furnace structure 1. In this embodiment, the pressure regulating unit includes a vacuum pump and related valves. By evacuating the furnace structure 1 or introducing inert gas under a low-pressure atmosphere, a controllable deposition environment is achieved. The pressure is adjusted at different growth stages to coordinate the decomposition of the silicon source gas and crystal growth.

[0057] The carrier platform 41 unit includes a carrier platform 41 and a position adjustment mechanism 42 for changing the relative position between the carrier platform 41 and the furnace structure 1 during the silicon ingot deposition process. By appropriately changing the relative position between the carrier platform 41 and the furnace structure 1 during silicon ingot growth, the deposition rate is optimized and the crystal quality of the silicon ingot is improved.

[0058] In one embodiment of the present invention, the position adjustment mechanism 42 includes a mechanical lifting mechanism, a hydraulic moving device or other structures capable of changing the position of the supporting platform 41 relative to the furnace structure 1 .

[0059] In specific applications, the mechanical lifting mechanism can achieve high-precision displacement through the cooperation of the lead screw and the motor, and can be combined with a grating ruler or encoder to monitor the platform position to dynamically adjust the silicon ingot growth interface, thereby obtaining more stable crystal quality in different thermal field areas. The hydraulic moving device moves the supporting platform 41 in a high-temperature environment through a hydraulic cylinder, and can smoothly adjust the relative position within a large stroke range to meet the preparation needs of silicon ingots of various sizes. Other structures that can change the position of the supporting platform 41 relative to the furnace structure 1 include moving mechanisms that can change position or angle in multiple directions, which can flexibly track and position the growth surface of the silicon ingot while maintaining the internal heating and atmosphere environment of the furnace structure 1 unchanged.

[0060] By adopting the above-mentioned multiple types of variable position adjustment mechanisms 42, the temperature field, silicon source gas flow rate and pressure environment can be coordinated during the silicon ingot deposition process, so that the growth surface is always in the optimal deposition state, thereby effectively suppressing the accumulation of thermal stress and reducing the concentration of impurity crystallization positions, further improving the internal uniformity and surface density of the silicon ingot, reducing the waste of raw materials and the defect rate in the subsequent processing process, and thus obtaining high-quality silicon ingot products.

[0061] The exhaust port 5 is used to exhaust unreacted silicon source gas or byproduct gas. The exhaust port 5 is connected to the exhaust gas treatment system to promptly exhaust unreacted silicon source gas or byproduct gas during the silicon ingot growth process, thereby reducing impurity accumulation and contamination risks, and improving the purity and stability of the silicon ingot.

[0062] In one embodiment, the exhaust port 5 is connected to the bottom of the reaction chamber 10 , specifically to the edge of the bottom of the reaction chamber 10 .

[0063] The present invention, with the help of the cooperation of the above-mentioned furnace body structure 1, temperature control unit, pressure adjustment unit, position adjustment mechanism 42, gas inlet 2 and exhaust port 5, can obtain a silicon ingot preparation environment that is relatively stable in terms of growth rate and temperature field uniformity, reduce crystal defects caused by overheating or stress concentration, significantly improve preparation efficiency and yield, and provide a good crystal quality foundation for subsequent annealing, doping or slicing processes.

[0064] In one embodiment of the present invention, a silicon ingot preparation system is further provided, comprising: the above-mentioned silicon ingot preparation device, an automatic control module and a gas source delivery mechanism.

[0065] The automated control module is used to control the temperature control unit, position adjustment mechanism 42, and pressure management unit. This automated control module can utilize an industrial control computer with multi-channel data acquisition and control capabilities. By exchanging signals with the temperature control unit, position adjustment mechanism 42, and pressure management unit, it automatically adjusts the resistance heating or induction heating power, the movement of the support platform 41, and the internal pressure of the furnace structure 1 based on a pre-set growth recipe or real-time monitoring data.

[0066] The gas source delivery mechanism is used to provide silicon source gas and carrier gas and introduce them into the reaction chamber 10. The gas source delivery mechanism may include a silicon source gas cylinder such as high-purity silane or chlorosilane and a precision mass flow controller, in conjunction with a carrier gas channel such as argon, hydrogen, or nitrogen, which enters the reaction chamber 10 through multiple gas pipelines and cooperates with the exhaust port 5 to complete the exhaust and treatment.

[0067] This system can be used to collaboratively manage the silicon ingot preparation process on the same automated platform. The system integrates the multi-zone temperature control of the furnace structure 1, the dynamic positioning of the position adjustment mechanism 42, and the precise vacuum or ventilation function of the pressure regulation unit. It can effectively schedule the temperature, pressure and material supply throughout the silicon ingot growth process, ensure the efficient utilization of silicon source gas and the stability of the deposition rate, reduce the crystal defect rate and improve the overall production efficiency, and provide a reliable and feasible integrated solution for the preparation of large-scale high-quality silicon ingots.

[0068] It should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation method can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0069] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a silicon ingot, characterized in that: The following steps are involved: regulating the pressure of the reaction chamber to be lower than atmospheric pressure; heating the reaction chamber to a predetermined temperature through a temperature control unit; introducing a silicon source gas and a carrier gas into the reaction chamber and maintaining the temperature at the predetermined temperature for a predetermined time; increasing the temperature of the reaction chamber to decompose the silicon source gas; The reaction chamber where the carrying platform is located is locally cooled to deposit silicon ingots on the carrying platform.

2. The method for preparing a silicon ingot according to claim 1, wherein: The pressure adjustment includes placing the reaction chamber in a vacuum, wherein the vacuum degree is 10 -3 Pa and below.

3. The method for preparing a silicon ingot according to claim 1, wherein: The predetermined temperature is 200°C-400°C; and / or, the scheduled time is 0.5h-1h; and / or, raising the temperature of the reaction chamber to 550° C.-900° C. to decompose the silicon source gas; And / or, the local cooling rate is 1°C / min-10°C / min, cooling to 400°C-550°C.

4. The method for preparing a silicon ingot according to claim 1, wherein: The silicon source gas includes at least one of trichlorosilane, silicon tetrachloride, and silane gas.

5. The method for preparing a silicon ingot according to claim 1, wherein: During the process of forming the silicon ingot by deposition, the height of the top of the carrying platform is lowered by the position adjustment mechanism.

6. The method for preparing a silicon ingot according to claim 1, wherein: After the silicon ingot is deposited, hydrogen or an inert gas is introduced into the reaction chamber to exhaust unreacted silicon source gas and / or by-product gas.

7. A silicon ingot preparation device, characterized in that: include: A furnace structure for providing a reaction chamber; A gas inlet port, used to introduce silicon source gas and carrier gas into the reaction chamber; a temperature control unit, cooperating with the furnace structure to adjust the temperature of the reaction chamber; A pressure regulating unit, used for evacuating or introducing gas into the furnace structure; A carrying platform unit, comprising a carrying platform and a position adjustment mechanism for changing the relative position between the carrying platform and the furnace structure during the silicon ingot deposition process; and an exhaust port for exhausting unreacted silicon source gas or by-product gas.

8. The silicon ingot preparation device according to claim 7, characterized in that: The temperature control unit is selected from an induction heating component, a resistance heating unit, or a microwave heating system; And / or, the temperature control unit includes a gas source heating device arranged at the gas inlet, and a furnace chamber heating device arranged around at least a portion of the reaction chamber; And / or, the furnace structure has at least two temperature control zones inside, and the at least two temperature control zones are arranged along the height direction of the reaction chamber, and the supporting platform is located in any one of the second and following temperature control zones from the top to the bottom.

9. The silicon ingot preparation device according to claim 7 or 8, characterized in that: The position adjustment mechanism includes a mechanical lifting mechanism and a hydraulic moving device.

10. A silicon ingot preparation system, characterized in that: include: The silicon ingot preparation device according to any one of claims 7 to 9; An automation control module, configured to control the temperature control unit, the position adjustment mechanism, and the pressure management unit; The gas source delivery mechanism is used to provide silicon source gas and carrier gas and introduce them into the reaction chamber.

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