Method for preparing antimony-nitrogen co-doped single crystal silicon and antimony-nitrogen co-doped single crystal silicon

Abstract

The present invention discloses a method for preparing antimony-nitrogen co-doped single crystal silicon and antimony-nitrogen co-doped single crystal silicon. The method for preparing antimony-nitrogen co-doped single crystal silicon comprises: obtaining the number N of times silicon material is put into a crucible; determining that N is greater than or equal to 2, and simultaneously putting dopants into a single crystal furnace while putting silicon material, the dopants including antimony material; and introducing nitrogen and argon into the single crystal furnace. According to the method for preparing antimony-nitrogen co-doped single crystal silicon of the present invention, the method for preparing antimony-nitrogen co-doped single crystal silicon can improve the utilization rate of the crucible, reduce the void defects of the crystal rod and eliminate dislocations, and can also improve the mechanical strength of the crystal rod and reduce the oxygen content, thereby improving the quality of the single crystal silicon.

Description

Technical Field

[0001] The invention relates to the technical field of single crystal silicon manufacturing, and in particular to a method for preparing antimony and nitrogen co-doped single crystal silicon and the antimony and nitrogen co-doped single crystal silicon. Background Art

[0002] In the related art, single crystal silicon is prepared by methods such as the Czochralski method. However, during the crystal pulling process, the crystal rod is prone to produce void defects and dislocations, and the mechanical strength of the crystal rod cannot be guaranteed, which in turn affects the quality of the single crystal silicon. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method for preparing antimony-nitrogen co-doped single crystal silicon, which can improve the utilization rate of the crucible, reduce the void defects of the crystal rod and eliminate dislocations, and can also improve the mechanical strength of the crystal rod and reduce the oxygen content, thereby improving the quality of the single crystal silicon.

[0004] The present invention also provides an antimony-nitrogen co-doped single crystal silicon, which is manufactured according to the above-mentioned method for preparing the antimony-nitrogen co-doped single crystal silicon.

[0005] The method for preparing antimony-nitrogen co-doped single crystal silicon according to an embodiment of the present invention includes: obtaining the number N of times silicon material is added into a crucible; determining that N is greater than or equal to 2, and adding dopants into a single crystal furnace while adding silicon material, the dopants including antimony material; and introducing nitrogen and argon into the single crystal furnace.

[0006] According to the method for preparing antimony-nitrogen co-doped single crystal silicon of the embodiment of the present invention, when the number of times of adding silicon material into the crucible is greater than or equal to 2, adding dopant antimony into the single crystal furnace at the same time as adding silicon material, and then introducing nitrogen and argon into the single crystal furnace, the batch feeding can increase the total amount of silicon material and dopant added into the crucible, and can also improve the doping efficiency, thereby improving the utilization rate of the crucible and the production efficiency of single crystal silicon. Nitrogen doping can reduce the void defects of the crystal rod during the crystal pulling process and eliminate dislocations, can increase the minority carrier life of the crystal rod, help to improve the mechanical strength of the single crystal silicon, thereby reducing the fragmentation rate during the slicing process, and can also reduce the oxygen content, thereby improving the quality of the single crystal silicon.

[0007] According to some embodiments of the present invention, after the dopant is added into the crucible, nitrogen and argon are introduced into the single crystal furnace during the entire crystal pulling process.

[0008] According to some embodiments of the present invention, the single crystal furnace is connected to a first ventilation pipe and a second ventilation pipe, and introducing nitrogen and argon into the single crystal furnace includes: introducing nitrogen into the single crystal furnace through the first ventilation pipe, and introducing argon into the single crystal furnace through the second ventilation pipe.

[0009] In some embodiments of the present invention, the intake flow rate of nitrogen in the first ventilation pipe is a, and satisfies: 10 L / min≤a≤60 L / min.

[0010] In some embodiments of the present invention, the intake flow rate of argon gas in the second ventilation pipe is b, and satisfies: 50 L / min≤b≤200 L / min.

[0011] According to some embodiments of the present invention, the nitrogen content concentration in the crystal rod obtained by the crystal pulling process is c, and satisfies: 0.1 ppma≤c≤1 ppma.

[0012] According to some embodiments of the present invention, the step of simultaneously adding dopants to the single crystal furnace while adding silicon material includes: obtaining the total weight of the silicon material added to the single crystal furnace at one time; and determining the weight of the antimony material added to the single crystal furnace at one time based on the total weight of the silicon material added at one time.

[0013] In some embodiments of the present invention, determining the weight of the antimony material added to the single crystal furnace at a time according to the total weight of the silicon material added at a time includes: the concentration of the antimony material in the silicon material is d, and satisfies: 9000ppbw≤d≤20000ppbw.

[0014] According to some embodiments of the present invention, the antimony concentration in the crystal rod obtained through the crystal pulling process is e, and satisfies: 100ppbw≤e≤200ppbw.

[0015] According to some embodiments of the present invention, after silicon material is first added into the crucible and before the first added silicon material is melted, argon gas is introduced into the single crystal furnace.

[0016] According to some embodiments of the present invention, the crystal pulling process includes: melting the material to completely melt the silicon material and the antimony material; seeding the crystal to rotate and slowly descend and immerse the seed crystal in the liquid silicon material, and then gradually rise the seed crystal and leave the liquid surface of the liquid silicon material to form a crystal rod; necking to quickly pull the seed crystal upward; shouldering to slow down the speed of pulling the crystal rod upward so that the diameter of the newly crystallized crystal rod increases rapidly until it reaches a preset crystal rod diameter; isodiametric growth to control the crystal rod to grow isodiametrically to a preset length with the preset crystal rod diameter; finishing to increase the speed of pulling the crystal rod upward so that the diameter of the newly crystallized crystal rod gradually decreases until the crystal rod leaves the liquid surface of the liquid silicon material.

[0017] The antimony-nitrogen co-doped single crystal silicon according to the embodiment of the present invention is manufactured according to the above-mentioned method for preparing the antimony-nitrogen co-doped single crystal silicon.

[0018] According to the antimony-nitrogen co-doped single crystal silicon of the embodiment of the present invention, when the number of times of adding silicon material into the crucible is greater than or equal to 2, the dopant antimony is added into the single crystal furnace at the same time as the silicon material is added into the crucible, and then nitrogen and argon are introduced into the single crystal furnace. The batch feeding can increase the total amount of silicon material and dopant added into the crucible, and can also improve the doping efficiency, thereby improving the utilization rate of the crucible and the production efficiency of single crystal silicon. Nitrogen doping can reduce the void defects of the crystal rod during the crystal pulling process and eliminate dislocations, can increase the minority carrier life of the crystal rod, help to improve the mechanical strength of the single crystal silicon, thereby reducing the fragmentation rate during the slicing process, and can also reduce the oxygen content, thereby improving the quality of the single crystal silicon.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 It is a logical schematic diagram of a method for preparing antimony and nitrogen co-doped single crystal silicon according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Reference below Figure 1 A method for preparing antimony and nitrogen co-doped single crystal silicon according to an embodiment of the present invention is described.

[0026] like Figure 1 As shown, the method for preparing antimony-nitrogen co-doped single crystal silicon according to an embodiment of the present invention comprises:

[0027] Obtain the number N of times silicon material is added into the crucible;

[0028] Determine that N is greater than or equal to 2, and add dopants into the single crystal furnace at the same time as silicon material, the dopants including antimony material;

[0029] Nitrogen and argon are introduced into the single crystal furnace.

[0030] Specifically, at the initial stage of loading, high-purity polysilicon raw material or recycled silicon material is placed in the quartz crucible of the single crystal furnace. The silicon material is usually in block form, and there are large gaps between the multiple block silicon materials in the crucible. Therefore, the crucible is preheated first to melt the block silicon material in the crucible, and the gaps between the multiple block silicon materials disappear. After the silicon material becomes liquid, the upper surface drops, so that silicon material and dopants can continue to be added to the crucible, which can improve the quality of silicon material and dopants added to the crucible before crystal pulling, so that more single crystal silicon can be prepared after each feeding, thereby improving the utilization rate of the crucible and the production efficiency of single crystal silicon.

[0031] When it is determined that the number of times the silicon material is added to the crucible is greater than or equal to 2, the antimony material is added to the single crystal furnace at the same time as the silicon material, so that the dopant is added after sufficient silicon material is added, and the batch feeding can reduce the volatilization and loss of the dopant at high temperature, which is conducive to improving the doping efficiency. After the dopant is added to the crucible, the melting material is started and the heating is continued, and then the crystal pulling process is carried out by the Czochralski method to obtain a crystal rod, thereby producing a single crystal silicon.

[0032] The process of introducing impurities into single crystal silicon to change the atomic structure and electronic properties of single crystal silicon. Antimony as a dopant can change the conductivity of single crystal silicon. Antimony is an n-type Group V element that can provide free electrons, thereby increasing the conductivity of single crystal silicon, and can also improve the reliability of the resistivity and mechanical properties of single crystal silicon, thereby improving the quality of the crystal rod.

[0033] Before crystal pulling, nitrogen and argon are introduced into the single crystal furnace. Nitrogen and argon can be used as protective gases to prevent harmful substances such as oxygen and moisture in the single crystal furnace from entering the crystal rod, thereby ensuring the purity and quality of single crystal silicon.

[0034] Among them, nitrogen doping can significantly increase the critical shear stress of dislocation slip in CZ silicon single crystals, thereby inhibiting dislocation slip, reducing the void defects of the crystal rod during the crystal pulling process, and increasing the minority carrier lifetime of the crystal rod, which helps to improve the mechanical strength of single crystal silicon, thereby reducing the fragmentation rate during the crystal rod slicing process, that is, improving the slicing yield, and further improving the quality of single crystal silicon. The interaction between nitrogen and oxygen can effectively reduce the oxygen content in the single crystal furnace, thereby reducing the oxygen content of single crystal silicon, thereby improving the crystal quality of single crystal silicon.

[0035] According to the method for preparing antimony-nitrogen co-doped single crystal silicon of the embodiment of the present invention, when the number of times of adding silicon material into the crucible is greater than or equal to 2, adding dopant antimony into the single crystal furnace at the same time as adding silicon material, and then introducing nitrogen and argon into the single crystal furnace, the batch feeding can increase the total amount of silicon material and dopant added into the crucible, and can also improve the doping efficiency, thereby improving the utilization rate of the crucible and the production efficiency of single crystal silicon. Nitrogen doping can reduce the void defects of the crystal rod during the crystal pulling process and eliminate dislocations, can increase the minority carrier life of the crystal rod, help to improve the mechanical strength of the single crystal silicon, thereby reducing the fragmentation rate during the slicing process, and can also reduce the oxygen content, thereby improving the quality of the single crystal silicon.

[0036] In some embodiments of the present invention, after dopants are added to the crucible, nitrogen and argon are introduced into the single crystal furnace throughout the crystal pulling process. This ensures that nitrogen reacts with silicon materials and is doped into the crystal rod during the entire crystal pulling process, improves the uniformity of nitrogen doping in the crystal rod, reduces the void defects of the crystal rod during the crystal pulling process, eliminates dislocations, and improves the mechanical strength of the crystal rod, thereby ensuring the effect of improving the quality of single crystal silicon. It can also ensure that nitrogen and argon can protect the crystal rod during the entire crystal pulling process, thereby ensuring the purity and quality of single crystal silicon.

[0037] In some embodiments of the present invention, Figure 1 As shown, the single crystal furnace is connected with a first vent pipe and a second vent pipe, and nitrogen and argon are introduced into the single crystal furnace including:

[0038] Nitrogen is introduced into the single crystal furnace through the first ventilation pipe, and argon is introduced into the single crystal furnace through the second ventilation pipe.

[0039] Nitrogen and argon are introduced into the single crystal furnace through the first vent pipe and the second vent pipe respectively, so that the flow rates of nitrogen and argon can be controlled respectively, thereby improving the control accuracy and convenience of the nitrogen and argon intake amounts.

[0040] In some embodiments of the present invention, the nitrogen intake flow rate in the first ventilation pipe is a, and satisfies: 10L / min≤a≤60L / min. If the amount of nitrogen introduced is too small, it is impossible to ensure that a sufficient amount of nitrogen is doped into the crystal rod, which affects the improvement of the performance of the single crystal silicon by nitrogen doping. If the amount of nitrogen introduced is too large, it will cause a waste of nitrogen resources. When the nitrogen doping concentration exceeds a certain threshold, its inhibitory effect on dislocation slip will be weakened.

[0041] Therefore, the nitrogen intake flow rate in the first ventilation pipe is controlled at 10L / min-60L / min, which will not cause waste of nitrogen energy, thereby controlling costs, and can ensure that nitrogen doping reduces the void defects of the crystal rod, eliminates dislocations, and improves the mechanical strength of the crystal rod, thereby ensuring the effect of improving the quality of single crystal silicon.

[0042] In some embodiments of the present invention, the intake flow rate of argon gas in the second ventilation pipe is b, and satisfies: 50L / min≤b≤200L / min. If the amount of argon gas introduced is too small, the protective effect of argon gas on the crystal rod cannot be guaranteed. If the amount of argon gas introduced is too large, it will cause a waste of argon gas resources. Therefore, the intake flow rate of argon gas in the second ventilation pipe is controlled at 50L / min-200L / min, which will not cause energy waste of argon gas, thereby controlling costs, and can ensure the protective effect of argon gas on the crystal rod, preventing harmful substances such as oxygen and moisture in the single crystal furnace from entering the crystal rod, thereby ensuring the purity and quality of single crystal silicon.

[0043] In some embodiments of the present invention, the nitrogen concentration in the crystal rod obtained by the crystal pulling process is c, and satisfies: 0.1ppma≤c≤1ppma. If the nitrogen concentration in the crystal rod is too low, the improvement of the performance of single crystal silicon by nitrogen doping will be affected. If the nitrogen concentration in the crystal rod is too high, the inhibitory effect of nitrogen doping on dislocation slip will be weakened.

[0044] Therefore, controlling the nitrogen content in the crystal rod to 0.1ppma-1ppma can keep the effect of nitrogen doping in reducing the void defects of the crystal rod, eliminating dislocations, and improving the mechanical strength of the crystal rod within the optimal range, thereby ensuring the effect of improving the quality of single crystal silicon. It can not only ensure the electrical properties and mechanical strength of single crystal silicon, but also avoid affecting the integrity and yield of the crystal rod, and reduce the difficulty of realization.

[0045] In some embodiments of the present invention, Figure 1 As shown, the doping materials are added into the single crystal furnace at the same time as the silicon material, including:

[0046] Obtaining the total weight of silicon material added into the single crystal furnace at one time;

[0047] The weight of the antimony material added to the single crystal furnace at one time is determined according to the total weight of the silicon material added at one time.

[0048] It is understandable that the content of doping elements determines the electrical properties of single crystal silicon, such as conductivity type and resistivity. Therefore, the ratio of silicon material and dopants directly affects the resistivity of single crystal silicon, and thus affects its electrical properties and application areas. The weight of antimony material added to the single crystal furnace at a time is determined based on the total weight of silicon material added at a time, which can control the proportion of dopants, help maintain the integrity of the crystal structure, and avoid crystal defects caused by improper doping. Controlling the ratio of silicon material and dopants by weight also facilitates precise control of the amount of dopants added.

[0049] In some embodiments of the present invention, determining the weight of the antimony material added to the single crystal furnace at a time according to the total weight of the silicon material added at a time includes:

[0050] The concentration of antimony material in silicon material is d, and satisfies: 9000ppbw≤d≤20000ppbw.

[0051] If the concentration of antimony in silicon is too high, antimony will react violently with silicon liquid, which may cause splashing and destroy the furnace atmosphere, thus affecting the crystal formation rate, resulting in low crystal yield and high production cost. Excessive concentration may also reduce the integrity of the crystal and affect the electrical properties of the crystal. If the concentration of the dopant antimony is too low, the resistivity of the grown single crystal silicon may not reach the required resistivity range, and the doping efficiency is not high. Therefore, it is necessary to control the concentration of antimony in silicon to 9000ppbw-20000ppbw, which can not only ensure the resistivity of single crystal silicon, but also avoid affecting the integrity and yield of the crystal.

[0052] In some embodiments of the present invention, the antimony concentration in the crystal rod obtained by the crystal pulling process is e, and satisfies: 100ppbw≤e≤200ppbw.

[0053] If the concentration of antimony in the crystal rod is too high, the excessively high antimony concentration may reduce the integrity and uniformity of the crystal, affect the growth quality of the crystal, reduce the resistance to dislocation movement, and affect the mechanical properties of the crystal. If the concentration of antimony in the crystal rod is too low, it will lead to insufficient conductivity and fail to effectively improve the crystal integrity of heavily antimony-doped single crystal silicon. Therefore, it is necessary to control the concentration of antimony in the crystal rod to 100ppbw-200ppbw, which can not only ensure the electrical properties and mechanical strength of single crystal silicon, but also avoid affecting the integrity, uniformity and yield of the crystal rod, and reduce the difficulty of realization.

[0054] In some embodiments of the present invention, Figure 1As shown, after the silicon material is first added to the crucible and before the first silicon material is melted, argon gas is introduced into the single crystal furnace. Silicon material reacts easily with oxygen at high temperature, resulting in oxidation. Oxidation not only reduces the purity of single crystal silicon, but also introduces defects, seriously affecting its performance. Argon gas can isolate the air and prevent oxygen from entering the sub-chamber, thereby protecting the silicon material from oxidation. Argon gas can carry away volatile oxide impurities and other harmful substances during its flow, which helps to keep the growth environment of single crystal silicon clean and pure. By controlling the atmosphere in the sub-chamber, defects such as voids and inclusions generated during the growth process of single crystal silicon can be reduced, which is beneficial to improving the performance and service life of single crystal silicon.

[0055] According to some embodiments of the present invention, Figure 1 As shown, the crystal pulling process includes:

[0056] Melting materials to completely melt silicon and antimony;

[0057] Seeding, which makes the seed crystal rotate and slowly descend and immerse the seed crystal in the liquid silicon material, and then makes the seed crystal gradually rise and leave the liquid surface of the liquid silicon material to form a crystal rod;

[0058] Neck shrinkage, quickly pull the seed crystal upward;

[0059] The shoulder is released to slow down the speed of pulling the crystal rod upward, so that the diameter of the newly crystallized crystal rod increases rapidly until it reaches the preset crystal rod diameter;

[0060] Constant diameter growth, controlling the crystal rod to grow constant diameter to a preset length with a preset crystal rod diameter;

[0061] At the end, the speed of pulling the crystal rod upward is increased, so that the diameter of the newly crystallized crystal rod gradually decreases until the crystal rod leaves the surface of the liquid silicon material.

[0062] It is understandable that after the loading is completed, the crucible is placed in the graphite crucible in the single crystal furnace, and then the single crystal furnace is evacuated to maintain it within a certain pressure range, and then filled with a certain flow and pressure of protective gas, and finally heated to a temperature exceeding the melting point of the silicon material 1412°C to fully melt it. When the silicon crystal rod grows, the oriented seed crystal is first fixed on the rotating seed crystal rod, and then the seed crystal is slowly lowered, and paused for a moment 10mm away from the liquid silicon surface, so that the seed crystal temperature is as close to the molten silicon temperature as possible to reduce possible thermal shock. Then the seed crystal is gently immersed in the molten silicon, so that the head first dissolves a small amount, and then forms a solid-liquid interface with the molten silicon, and then the seed crystal gradually rises, and the temperature of the silicon connected to the seed crystal and leaving the solid-liquid interface decreases, forming a single crystal silicon, thereby completing the seeding stage.

[0063] After seeding is completed, the seed crystal is quickly pulled upward, the growth rate of the crystal rod is accelerated, and the diameter of the newly crystallized single crystal silicon will be smaller than the diameter of the seed crystal. The necking removes the dislocation-free seed crystal with surface mechanical damage. Seeding to the target length, slowing down the pulling speed of the crystal rod, lowering the temperature, and rapidly increasing the diameter. The shouldering process adjusts the shoulder shape by matching the diameter with the temperature. After the shoulder is released to the target diameter, it is necessary to quickly change the growth direction of the crystal rod from the horizontal to the vertical direction, increase the pulling speed, and the crystal rod stops growing horizontally. When the diameter no longer increases, the shouldering is completed.

[0064] When the shoulder reaches the predetermined crystal rod diameter, the growth rate of the crystal rod accelerates and maintains an almost fixed speed, so that the crystal rod maintains a fixed diameter growth. Equal diameter is the main part of the crystal rod growth, and the raw material of the single crystal silicon wafer can be obtained. If the single crystal silicon is directly separated from the liquid surface after the growth is completed, the thermal stress will produce a large number of dislocations at the interface, and extend upward by about a diameter, making the tail of the crystal rod unusable. Therefore, when the growth of the crystal rod is nearing the end, the growth rate is accelerated again, and the temperature of the silicon melt is increased at the same time, so that the diameter of the crystal rod continues to shrink, forming a cone, and finally the crystal rod leaves the liquid surface, the finishing stage ends, and the growth of single crystal silicon is completed.

[0065] The antimony-nitrogen co-doped single crystal silicon according to the embodiment of the present invention is manufactured according to the above-mentioned method for preparing the antimony-nitrogen co-doped single crystal silicon.

[0066] According to the antimony-nitrogen co-doped single crystal silicon of the embodiment of the present invention, when the number of times of adding silicon material into the crucible is greater than or equal to 2, the dopant antimony is added into the single crystal furnace at the same time as the silicon material is added into the crucible, and then nitrogen and argon are introduced into the single crystal furnace. The batch feeding can increase the total amount of silicon material and dopant added into the crucible, and can also improve the doping efficiency, thereby improving the utilization rate of the crucible and the production efficiency of single crystal silicon. Nitrogen doping can reduce the void defects of the crystal rod during the crystal pulling process and eliminate dislocations, can increase the minority carrier life of the crystal rod, help to improve the mechanical strength of the single crystal silicon, thereby reducing the fragmentation rate during the slicing process, and can also reduce the oxygen content, thereby improving the quality of the single crystal silicon.

[0067] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0068] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for preparing antimony-nitrogen co-doped single crystal silicon, characterized in that: include: Obtain the number N of times silicon material is added into the crucible; Determine that N is greater than or equal to 2, and add dopants into the single crystal furnace while adding silicon material, wherein the dopants include antimony material; Nitrogen and argon are introduced into the single crystal furnace.

2. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: After the dopant is added into the crucible, nitrogen and argon are introduced into the single crystal furnace during the entire crystal pulling process.

3. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: The single crystal furnace is connected to a first vent pipe and a second vent pipe, and the introduction of nitrogen and argon into the single crystal furnace comprises: Nitrogen is introduced into the single crystal furnace through the first ventilation pipe, and argon is introduced into the single crystal furnace through the second ventilation pipe.

4. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 3, characterized in that: The intake flow rate of nitrogen in the first ventilation pipe is a, and satisfies: 10L / min≤a≤60L / min.

5. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 3, characterized in that: The intake flow rate of argon gas in the second ventilation pipe is b, and satisfies: 50L / min≤b≤200L / min.

6. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: The nitrogen content concentration in the crystal rod obtained by the crystal pulling process is c, and satisfies: 0.1 ppma≤c≤1 ppma.

7. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: The step of simultaneously adding dopants into the single crystal furnace and silicon material comprises: Obtaining the total weight of silicon material added into the single crystal furnace at a single time; The weight of the antimony material added into the single crystal furnace at one time is determined according to the total weight of the silicon material added at one time.

8. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 7, characterized in that: The step of determining the weight of the antimony material added to the single crystal furnace at a time according to the total weight of the silicon material added at a time comprises: The concentration of the antimony material in the silicon material is d, and satisfies: 9000ppbw≤d≤20000ppbw.

9. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: The antimony concentration in the crystal rod obtained by the crystal pulling process is e, and satisfies: 100ppbw≤e≤200ppbw.

10. The method for preparing single crystal silicon according to claim 1, characterized in that: After silicon material is first added into the crucible and before the first added silicon material is melted, argon gas begins to be introduced into the single crystal furnace.

11. The method for preparing antimony-nitrogen co-doped single crystal silicon according to claim 1, characterized in that: The crystal pulling process includes: Melting material, so that the silicon material and the antimony material are completely melted; Seeding, which makes the seed crystal rotate and slowly descend and immerse the seed crystal in the liquid silicon material, and then makes the seed crystal gradually rise and leave the liquid surface of the liquid silicon material to form a crystal rod; Neck shrinking, and pulling the seed crystal upward rapidly; The shoulder is released to slow down the speed of pulling the crystal rod upward, so that the diameter of the newly crystallized crystal rod increases rapidly until it reaches a preset crystal rod diameter; Isometric growth, controlling the crystal rod to grow isometrically to a preset length with the preset crystal rod diameter; At the end, the speed of pulling the crystal rod upward is increased, so that the diameter of the newly crystallized crystal rod gradually decreases until the crystal rod leaves the liquid surface of the liquid silicon material.

12. An antimony-nitrogen co-doped single crystal silicon, characterized in that: The method for preparing antimony-nitrogen co-doped single crystal silicon is according to any one of claims 1 to 11.

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