Method for eliminating *-shaped stripes in heavily boron-doped monocrystalline silicon rod and product thereof
By adding preheating steps in the crystal pulling process, adjusting the positions of crucible and seed crystals, and passing in argon gas at a suitable temperature, the problem of defects in the internal meter-shaped stripes of heavy boron doped single crystal silicon rod is solved, and the purity of the crystal rod is improved and Productivity.
Patent Information
- Application Number
- CN202411518030.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2025-02-11
AI Technical Summary
The heavily boron doped single crystal silicon rod is prone to internal meter-shaped stripe defects during the drawing process. The prior art eliminates the problem by adding elements such as germanium, but increases the manufacturing cost and affects the quality of the crystal rod.
The preheating step is added based on the crystal pulling process, including adjusting the position of the crucible and seed crystal, staying for 30 min to 50 min for preheating, and passing the temperature to ±15 ℃ of the crystal drawing temperature during the lifting of the crucible and seed crystal The control flow rate of argon is 150 slm to 160 slm.
Through the preheating step, the temperature difference between seed crystal and molten silicon is reduced, and the occurrence of dislocation is avoided. The prepared crystal rod has no defects in the meter-shaped stripes, high purity, low melting rate, and improved production efficiency.
Smart Images
Figure CN119411215A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of semiconductors, and in particular relates to a method for eliminating cross-shaped stripes inside a heavily boron-doped single crystal silicon rod and a product thereof. Background Art
[0002] At present, silicon materials account for more than 98% of semiconductor devices. With the rapid development of global informatization, people's demand for information is growing rapidly. Information technology based on large-scale or even ultra-large-scale integrated circuits has become the cornerstone of today's economic activities and social life. Integrated circuits have entered the nanoscale stage, which has put forward higher requirements and challenges for single-crystal silicon materials as the basis of integrated circuits, thus making single-crystal silicon materials develop from 4 inches to the current mass-produced 12 inches, 18 inches... large size, high integrity and high uniformity.
[0003] Bo is the most important P-type electrically active impurity in silicon materials. Heavily boron-doped silicon wafers are widely used as epitaxial substrate materials for ultra-large-scale integrated circuits (ULSI). Although the introduction of a large number of Bo atoms improves the conductivity of silicon materials, the prepared single-crystal silicon materials also have certain defects. The defects are specifically manifested as follows: during the pulling process of a heavily boron-doped 12-inch crystal rod, it was found that although there were no slip lines on the surface of the crystal rod, after truncation, a cross-shaped defect was found on the surface of the rough sheet.
[0004] At present, in order to address the above defects, adding elements such as germanium during the crystal pulling process can eliminate the cross-shaped defects inside the crystal rod. However, the addition of elements such as germanium increases the manufacturing cost on the one hand, and on the other hand, the introduction of other elements affects the quality of the crystal rod and its effect during use. Therefore, it is necessary to solve the above cross-shaped defects from other aspects. Summary of the invention
[0005] In view of this, the present invention provides a method and product for eliminating the cross-shaped stripes inside a heavily boron-doped single crystal silicon rod, so as to solve the technical problem of the cross-shaped stripes inside a heavily boron-doped single crystal silicon rod in the prior art.
[0006] To achieve the above objectives, this application adopts the following scheme: A method for eliminating cross-shaped stripes inside a heavily boron-doped single crystal silicon rod comprises a preheating step, wherein the preheating step is performed between a stabilization step and a temperature test step, and the preheating step comprises the following steps: S11: adjusting the crucible position to a first preset position, and adjusting the seed crystal position to a second preset position; S12: when the crucible is located at the first preset position and the seed crystal is located at the second preset position, stay for 30 min to 50 min; S13: After staying for 30 min to 50 min, the crucible is lifted to a third preset position at a first preset rate, and the seed crystal is simultaneously lifted to a fourth preset position at a second preset rate. During the lifting of the crucible and the seed crystal, argon gas with a temperature of ±15°C of the seeding temperature is introduced downward from above the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm, so that the internal temperature of the seed crystal is more uniform.
[0007] Preferably, the preheating temperature in the preheating step is ±15°C of the seeding temperature.
[0008] Preferably, in step S11, the first preset position is the position where the crucible is at 0 mm.
[0009] Preferably, in step S11, the second preset position is to move the seed crystal to a position 5 mm to 10 mm away from the raw material liquid surface.
[0010] Preferably, in step S12, when the crucible is located at the first preset position and the seed crystal is located at the second preset position, the time of staying is 35 min to 45 min.
[0011] Preferably, in step S13, the first preset rate and the second preset rate are the same, both of which are 2 mm / min to 5 mm / min.
[0012] Preferably, in step S13, the third preset position is the position of the crucible when the crucible is raised from the first position by 170 mm to 200 mm, and the fourth preset position is the position of the seed crystal when the seed crystal is raised from the second position by 170 mm to 200 mm.
[0013] Preferably, in the step S13, when the crucible is lifted to the third preset position at the first preset rate, the rotation speed of the crucible is 1 rpm to 10 rpm.
[0014] A single crystal silicon rod product prepared by the method for eliminating the cross-shaped stripes inside a heavily boron-doped single crystal silicon rod as described in any one of the above items.
[0015] The technical solution adopted in this application can achieve the following beneficial effects: The present invention provides a method for eliminating the cross-shaped stripes inside a heavily boron-doped single crystal silicon rod. A preheating step is added on the basis of the crystal pulling process of the prior art. In this step, the crucible is first adjusted to a first preset position, and the seed crystal is lowered to the second preset position and stays for 30 minutes to 50 minutes, so that the seed crystal can be fully preheated, the temperature difference between the seed crystal and the molten silicon (liquid surface) is reduced, and dislocation is avoided during the crystal pulling process due to the large temperature difference between the seed crystal and the molten silicon. After staying for 30 minutes to 50 minutes, in this step, when the crucible and the seed crystal are synchronously lifted to a predetermined position at the same lifting rate, argon gas with a temperature of ±15°C of the seeding temperature is introduced from above the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm, the temperature inside the end of the seed crystal away from the crucible will increase during the downward flow of argon gas, and the temperature inside the end of the seed crystal close to the crucible can be evenly distributed during the downward flow, so that the temperature distribution of each position of the seed crystal can be more uniform, avoiding the defect of the prepared crystal rod having the cross-shaped stripes inside some positions due to the large temperature difference between the local temperature and the liquid surface, and because other elements for eliminating the cross-shaped defects inside the crystal rod are not added during the preparation process, the prepared crystal rod has a higher purity, thereby improving the production quality of the crystal rod; Furthermore, due to the method for eliminating the crisscross stripes inside the heavily boron-doped single crystal silicon rod provided by the present invention, the interior of the prepared crystal rod does not have crisscross stripe defects. Therefore, the remelting rate of the crystal rod prepared by this method is low, which can improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a macroscopic image of the cross section of the crystal rod prepared in Example 1 of the present application.
[0017] Figure 2 This is a microscopic image of the cross section of the crystal rod prepared in Example 1 of the present application.
[0018] Figure 3 It is a macroscopic picture of the cross section of the crystal rod prepared in Comparative Example 1 of the present application.
[0019] Figure 4 It is a microscopic picture of the cross section of the crystal rod prepared in Comparative Example 1 of the present application. DETAILED DESCRIPTION
[0020] In order to facilitate the understanding of the present application, the present application will be described more comprehensively below in conjunction with the accompanying drawings. And the preferred implementation of the present application is given. However, the present application can be implemented in many different forms and is not limited to the implementation described herein. On the contrary, the purpose of providing these implementations is to make the disclosure of the present application more thoroughly and comprehensively understood.
[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.
[0022] A method for eliminating cross-shaped stripes inside a heavily boron-doped single crystal silicon rod comprises a preheating step, wherein the preheating step is performed between a stabilization step and a temperature test step, and the preheating step comprises the following steps: S11: adjusting the crucible position to a first preset position, and adjusting the seed crystal position to a second preset position; Since the position of the crucible has changed after the last crystal pulling, in order to ensure the consistency of the next crystal pulling process, the position of the crucible needs to be adjusted to the first preset position. Since the seed crystal is far away from the crucible in the initial stage, it cannot be fully preheated or affects the preheating efficiency, so the seed crystal needs to be lowered to the second preset position; S12: when the crucible is located at the first preset position and the seed crystal is located at the second preset position, stay for 30 min to 50 min; The seed crystal can be fully preheated when it stays at the second preset position for 30 min to 50 min; In order to make the seed crystal heated more evenly and avoid the dislocation of some fine crystals due to the large temperature difference between the local temperature of the seed crystal and the molten silicon (liquid surface), resulting in a cross-shaped defect, S13: after staying for 30 minutes to 50 minutes, the crucible is lifted to the third preset position at a first preset rate, and the seed crystal is simultaneously lifted to the fourth preset position at a second preset rate. In the process of lifting the crucible and the seed crystal, argon gas with a temperature of ±15°C of the seeding temperature is introduced downward from the top of the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm. The temperature of the crucible is relatively high. During preheating, the internal temperature of the seed crystal at the end away from the crucible is relatively low, resulting in uneven temperature distribution inside the seed crystal. Therefore, when the crucible and the seed crystal are synchronously lifted to the predetermined position at the same lifting rate, argon gas with a temperature of ±15°C of the seeding temperature is introduced from the top of the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm, during the downward flow of argon gas, the temperature inside the end of the seed crystal away from the crucible will increase, and during the downward flow, the temperature inside the end of the seed crystal close to the crucible can be evenly distributed, thereby making the temperature distribution of each position of the seed crystal more uniform, avoiding the defect of cross-shaped stripes inside some positions of the prepared crystal rod due to the large temperature difference between the local temperature and the liquid surface.
[0023] In this embodiment, since the method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod disclosed in the present invention adds a step to the existing process steps for preparing single crystal silicon rods, namely, the preheating step, the other steps are the same as the process steps for preparing single crystal silicon rods in the prior art. In order to facilitate the understanding of the preheating step, only the order of the other process steps involved in the present invention is described in the following operation.
[0024] During operation, firstly, the material is melted: the raw material (such as polycrystalline silicon) is placed in a quartz crucible, and the raw material is heated in a single crystal furnace until it is completely melted; stabilization: ensure that the state of the molten silicon is stable without violent fluctuations, adjust the heating power and the furnace environment to keep the parameters such as the temperature and viscosity of the molten silicon stable; preheating: adjust the position of the crucible to the first preset position, slowly lower the seed crystal to the second preset position, and stay for 30 min to 50 min for preheating, then, raise the crucible to the third preset position at a first preset rate, and simultaneously raise the seed crystal to the fourth preset position at a second preset rate; temperature test: slowly lower the seed crystal to close to the surface of the molten silicon, determine the contact state of the seed crystal and the molten silicon by contact voltage and other methods, adjust the heating power to make the molten silicon temperature within a range suitable for the seed crystal to fuse, observe the fusion of the seed crystal tip, and confirm whether the temperature is appropriate; seeding: immerse the seed crystal in the molten silicon, start the crystal growth process, slowly pull the seed crystal and rotate it to control the crystal growth rate and morphology, monitor the crystal diameter and Growth quality to ensure successful seeding; shoulder release: after successful seeding, gradually increase the crystal diameter to the target size, control the pulling speed and temperature gradient to avoid excessive thermal stress and defects, monitor the change in crystal diameter, and ensure a smooth shoulder release process; equal diameter: after shoulder release is completed, keep the crystal diameter stable and perform equal diameter growth; finishing: when the crystal grows to a predetermined length, start the finishing operation, gradually reduce the crystal diameter until the crystal is separated from the molten silicon; cooling: take the grown single crystal silicon rod out of the furnace and place it in a cooling device to slowly cool the crystal to avoid thermal stress and cracks.
[0025] The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod provided in the present invention is improved in that a preheating step is added on the basis of the original process steps, and the preheating step is between the stabilization step and the temperature test step. During preheating, the position of the crucible is first adjusted to the first preset position, and the position of the seed crystal is adjusted to the second preset position, so that the seed crystal can be fully preheated. Through the preheating step, the temperature gradient inside the silicon rod raw material is reduced, so that the uneven stress distribution caused by the temperature difference in the subsequent growth process is alleviated. In this way, in the early stage of seeding, since the temperature of the seed crystal and the liquid surface is within a certain range, when the seed crystal contacts the liquid surface, the fine crystals drawn out can quickly eliminate dislocations, and there is no cross-shaped defect in the shoulder release process, and the cross-shaped defect in the equal diameter process has been eliminated; in this step, when the crucible and the seed crystal are synchronously lifted to the predetermined position at the same lifting rate, argon gas with a temperature of ±15°C of the seeding temperature is introduced from above the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm, the temperature inside the end of the seed crystal away from the crucible will increase during the downward flow of argon gas, and the temperature inside the end of the seed crystal close to the crucible can be uniformed during the downward flow, so that the temperature distribution of each position of the seed crystal can be more uniform, avoiding the defect of the cross-shaped stripes inside some positions of the prepared crystal rod due to the large temperature difference between the local temperature and the liquid surface, and because other elements for eliminating the cross-shaped defects inside the crystal rod are not added during the preparation process, the purity of the prepared crystal rod is relatively high; Furthermore, due to the method for eliminating the crisscross stripes inside the heavily boron-doped single crystal silicon rod provided by the present invention, the interior of the prepared crystal rod does not have crisscross stripe defects. Therefore, the remelting rate of the crystal rod prepared by this method is low, which can improve production efficiency.
[0026] Furthermore, in order to prevent the seed crystal from falling directly into the melt surface and causing excessive thermal shock, it needs to be slowly lifted to a certain distance to control the contact speed and method. By lifting the seed crystal, its distance from the melt surface can be more accurately controlled to facilitate subsequent welding and crystal growth steps.
[0027] The purpose of the temperature test step is to make the temperature of the seed crystal and the temperature of the molten silicon (liquid surface) within a certain range. Therefore, the preheating temperature in the preheating step is ±15°C of the seeding temperature.
[0028] Specifically, in step S11, the first preset position is the position where the crucible is at 0 mm.
[0029] Adjust the crucible position to the position where the crucible is at 0 mm, that is, return the crucible position to zero. During the preheating process, any slight position deviation may have an adverse effect on the growth of the crystal. The zeroing operation helps to eliminate these potential errors, improve the stability and success rate of crystal growth, and help ensure the repeatability and consistency of each crystal pulling process, thereby improving product quality and production efficiency.
[0030] Specifically, in step S11, the second preset position is to move the seed crystal to a position 5 mm to 10 mm away from the raw material liquid surface.
[0031] Due to the temperature difference between the seed crystal temperature and the raw material liquid surface (molten silicon) temperature, the seed crystal is moved to a position 5 mm to 10 mm away from the raw material liquid surface. The temperature around the raw material liquid surface is higher, which increases the temperature of the seed crystal and reduces the possibility of dislocation of the seed crystal due to temperature difference and surface tension during the crystal pulling process. When the distance between the seed crystal and the specific liquid surface is too small, the seed crystal may be melted. When the distance between the seed crystal and the specific liquid surface is too large, the preheating efficiency is affected. Therefore, it is more appropriate to move the seed crystal to a position 5 mm to 10 mm away from the raw material liquid surface.
[0032] In some preferred embodiments, in step S12, when the crucible is located at the first preset position and the seed crystal is located at the second preset position, the crucible stays for 35 to 45 minutes. The seed crystal stays at a position 5 mm to 10 mm away from the raw material liquid surface for 35 to 45 minutes to fully preheat, so as to avoid dislocations caused by a large temperature difference between the seed crystal and the molten silicon (raw material liquid surface) during the crystal pulling process, resulting in the formation of a defect of a cross-shaped stripe inside the single crystal silicon rod.
[0033] In step S13, the first preset rate and the second preset rate are the same, both of which are 2 mm / min to 5 mm / min. The purpose of synchronously lifting the crucible and the seed crystal at a rate of 2 mm / min to 5 mm / min is that the synchronous lifting can ensure that the temperature gradient between the seed crystal and the melt remains stable, which is conducive to uniform preheating of the crystal; avoid excessive thermal stress on the seed crystal due to temperature difference and surface tension, thereby preventing the seed crystal from bursting, obtaining a crystal of excellent quality in the subsequent crystal growth process, and preparing a single crystal silicon rod without internal cross-shaped stripe defects.
[0034] Specifically, in step S13, the third preset position is the position of the crucible when the crucible is raised from the first position by 170 mm to 200 mm; the fourth preset position is the position of the seed crystal when the seed crystal is raised from the second position by 170 mm to 200 mm.
[0035] Specifically, when the crucible is lifted to the third preset position at the first preset rate, the rotation speed of the crucible is 1 rpm to 10 rpm.
[0036] The single crystal silicon rod product prepared by the method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to any of the above items does not have the cross-shaped stripe defect inside, has high product quality, and has higher economic benefits.
[0037] The following specific experimental examples are used to further illustrate the technical solutions and technical effects of the present invention. It should be noted that the following experimental examples are only for further explaining the present invention and do not limit the technical solutions of the present invention. Example 1
[0038] The feeding amount is 280kg, the pure boron doping is 84g, the crystal pulling parameters are 12 inches, the heavily doped boron crystal rod with a crystal orientation of 100 crystal rods is pulled, and Res is 0.002-0.004Ω.cm; the crystal pulling process adopted is: material-stabilization-preheating-temperature test-seedling-shoulder release-shoulder rotation-equal diameter-finishing-cooling, wherein, during preheating, the crucible position is adjusted to a position of 0 mm, the seed crystal position is adjusted to a position 7mm away from the raw material liquid surface, and the seed crystal stays at this position for 40 min for sufficient preheating; then, the crucible is lifted up by 180mm at a rate of 3mm / min, and the seed crystal is simultaneously lifted up by 180mm at a rate of 3mm / min, the crucible speed is 5 rpm, and during the lifting process, argon gas with a temperature of ±7°C of the seeding temperature is introduced from the top of the end of the seed crystal away from the crucible, and the flow rate is controlled to be 155 slm; After the crystal rod is taken out of the furnace, there is no slip line on its surface. Cut off and take 2mm samples. After etching, select the best one. Figure 1 , Figure 2 , the melting rate of the crystal rod is 1.3; Depend on Figure 1 , Figure 2 It can be seen that after adding a new step on the basis of the original process steps, namely the preheating step, the surface of the prepared crystal rod has no slip line, and after cutting it, it is found that there is no cross-shaped defect inside the crystal rod. Since there is no cross-shaped defect inside the prepared crystal rod, the remelting rate of the crystal rod is only 1.3.
[0039] Comparative Example 1 The difference between this comparative example 1 and the above-mentioned embodiment 1 is that the crystal pulling process adopted is: material preparation - stabilization - temperature test - seeding - shoulder release - shoulder rotation - equal diameter - tailing - cooling, and the other steps are the same as those in the above-mentioned embodiment 1; After the crystal rod is taken out of the furnace, it is cut into 2mm samples and etched as follows: Figure 3 , Figure 4 The wafer surface has a crisscross defect, and the melting rate of the crystal rod is 1.8.
[0040] Depend on Figure 3 , Figure 4 It can be seen that the crystal rod prepared by the crystal pulling process in the prior art has no slip lines on the surface, but after cutting it, it is found that there is a cross-shaped defect inside the crystal rod, which affects the quality and use of the crystal rod. Since the prepared crystal rod has a cross-shaped defect inside, the remelting rate of the crystal rod is higher than the remelting rate in the above-mentioned Example 1.
[0041] Comparative Example 2 The difference between this comparative example 2 and the above-mentioned embodiment 1 is that, during the preheating process, the crucible position is adjusted to a position of 0 mm, the seed crystal position is adjusted to a position of 7 mm from the raw material liquid surface, the seed crystal stays at this position for 40 min, and the temperature test, seeding and other steps are directly carried out after sufficient preheating; After the ingot is taken out of the furnace, 2 mm samples are cut and etched selectively. It is found that some cross sections have crisscross defects (such as Figure 3 , Figure 4 ), some cross sections do not have Pozidriv defects (such as Figure 1 , Figure 2 ), the melting rate of the crystal rod is 1.5.
[0042] Comparative Example 2 shows that during the preheating step, the crucible position is only adjusted to a position of 0 mm, the seed crystal position is adjusted to a position 7 mm away from the raw material liquid surface, and the seed crystal stays at this position for 40 min for sufficient preheating; when the steps of lifting the crucible by 180 mm at a rate of 3 mm / min and simultaneously lifting the seed crystal by 180 mm at a rate of 3 mm / min and the crucible rotation speed is 5 rpm are omitted, some positions inside the prepared crystal rod have a cross-shaped defect, while others do not, which may be caused by uneven temperature of the seed crystal during preheating.
[0043] The above Example 1, Comparative Example 1 and Comparative Example 2 in combination with the accompanying drawings fully reflect that the method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod provided by the present application adds a new step to the crystal pulling process of the prior art, namely, the preheating step. In this step, the seed crystal is lowered to a position suitable for the liquid surface and stays for a predetermined time, so that the seed crystal can be fully preheated, the temperature difference between the seed crystal and the liquid surface can be reduced, and dislocations caused by the large temperature difference between the seed crystal and the molten silicon during the crystal pulling process can be avoided. In this step, the crucible and the seed crystal are synchronously lifted to the predetermined position at the same lifting rate. Argon gas with a temperature of ±15°C of the seeding temperature is introduced from above the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160slm, the temperature of the end of the seed crystal away from the crucible will increase during the downward flow of argon gas, and the temperature of the end of the seed crystal close to the crucible can be evenly distributed during the downward flow, so that the temperature distribution of each position of the seed crystal can be more uniform, avoiding the defect of the prepared crystal rod having a cross-shaped stripe inside the part of the prepared crystal rod due to the large difference between the local temperature and the temperature of the liquid surface, thereby improving the production quality of the crystal rod; Since the method for eliminating the crisscross stripes inside the heavily boron-doped single crystal silicon rod provided by the present invention does not have crisscross stripe defects inside the prepared crystal rod, the remelting rate of the crystal rod prepared by this method is low, which can improve production efficiency.
[0044] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.
Claims
1. A method for eliminating the cross-shaped stripes inside a heavily boron-doped single crystal silicon rod, characterized in that: The method comprises a preheating step, which is performed between the stabilization step and the temperature testing step, and the preheating step comprises the following steps: S11: adjusting the crucible position to a first preset position, and adjusting the seed crystal position to a second preset position; S12: when the crucible is located at the first preset position and the seed crystal is located at the second preset position, stay for 30 minutes to 50 minutes; S13: After staying for 30 min to 50 min, the crucible is lifted to a third preset position at a first preset rate, and the seed crystal is simultaneously lifted to a fourth preset position at a second preset rate. During the lifting of the crucible and the seed crystal, argon gas with a temperature of ±15°C of the seeding temperature is introduced downward from above the end of the seed crystal away from the crucible, and the flow rate is controlled to be 150 slm to 160 slm, so that the internal temperature of the seed crystal is more uniform.
2. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: The preheating temperature in the preheating step is ±15° C. of the seeding temperature.
3. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In the step S11, the first preset position is the position where the crucible is at 0 mm.
4. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In the step S11, the second preset position is to move the seed crystal to a position 5 mm to 10 mm away from the raw material liquid surface.
5. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In the step S12, when the crucible is located at the first preset position and the seed crystal is located at the second preset position, the positions are kept for 35 to 45 minutes.
6. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In the step S13, the first preset rate and the second preset rate are the same, both of which are 2 mm / min to 5 mm / min.
7. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In step S13, the third preset position is the position of the crucible when the crucible is raised from the first position by 170 mm to 200 mm, and the fourth preset position is the position of the seed crystal when the seed crystal is raised from the second position by 170 mm to 200 mm.
8. The method for eliminating the cross-shaped stripes inside the heavily boron-doped single crystal silicon rod according to claim 1, characterized in that: In the step S13, when the crucible is lifted to the third preset position at the first preset rate, the rotation speed of the crucible is 1 rpm to 10 rpm.
9. A single crystal silicon rod product prepared by the method for eliminating cross-shaped stripes inside a heavily boron-doped single crystal silicon rod according to any one of claims 1 to 8.