Single crystal silicon rod product, single crystal growth equipment and single crystal growth method

Abstract

The invention provides a single crystal silicon rod product, a single crystal growth device and a single crystal growth method.The single crystal growth device comprises a furnace body, a crucible, a heater, an insulation support, a supporting rod, a short circuit connecting block and a driving device, the heater is divided into a heating area and a short circuit area by the short circuit connecting block, and in the crystal growth process, the heating area and the short circuit area move upwards along with the crucible; the driving device is used for driving the supporting rod, so that the short-circuit connecting block slowly ascends, the length of a heating area of the heater is controlled, the regulation and control capability on temperature gradient distribution of a growth interface is enhanced, the uniformity of V / G of the growth interface is improved, and growth of a high-quality silicon single crystal rod product is promoted; the heating area of the heater is adjusted by adjusting the length of the heating area of the heater, so that the application process window of the heater is expanded, and the same heater can be used for producing various silicon single crystal rod products with different oxygen contents; and the production of the low-oxygen-content silicon single crystal rod product with the oxygen content of 3 nppma to 20 nppma is realized through the single crystal growth method.

Description

Technical Field

[0001] The present invention belongs to the technical field of single crystal silicon production, and in particular relates to a single crystal silicon rod product, single crystal growth equipment and a single crystal growth method. Background Art

[0002] As a commonly used single crystal growth method, the Czochralski method is also known as the Czochralski method. The characteristic of the Czochralski method is that in a straight-cylinder furnace, the polysilicon in a high-purity quartz crucible is melted by graphite resistance heating, and then the seed crystal is inserted into the melt surface for welding, while the seed crystal is rotated, and then the crucible is reversed, and the seed crystal is slowly lifted upward, and finally grows into a crystal rod of the required diameter and length through processes such as seeding, shoulder release, shoulder rotation, equal diameter growth, and tailing.

[0003] In the process of pulling single crystal silicon growth, the heater is one of the most important components of the thermal field system of pulling single crystal silicon. Its main function is to convert electrical energy into thermal energy to maintain the thermodynamic conditions required for single crystal growth. The formation and growth of micro defects in the process of pulling single crystal silicon growth follows the V / G theory proposed by Voronkov. The theory believes that the ratio of the pulling speed V to the temperature gradient G at the front of the growth interface is an important indicator for determining the defect distribution in single crystal silicon. By regulating the pulling speed V and the temperature gradient G at the front of the growth interface, a perfect single crystal without defects can be grown. In the process of pulling single crystal silicon growth, the pulling speed V on the growth interface is generally an approximately fixed value. Therefore, how to regulate the temperature gradient G at the front of the growth interface becomes particularly important. The heater and thermal field structure are the main factors affecting the temperature gradient G near the solid-liquid interface of the crystal growth. During the entire single crystal silicon growth process, it will continue to change with the changes in growth conditions such as the crucible position and the melt depth, thereby affecting the size of V / G, and then determining whether a perfect single crystal silicon can be grown.

[0004] In the thermal field system for pulling single crystal silicon in the prior art, the heating zone of the heater is generally fixed and cannot change with the change of single crystal silicon growth conditions. In the process of single crystal silicon growth, the liquid level depth of molten silicon generally decreases as the crucible position rises, causing the growth interface of the single crystal silicon to deviate more and more from the center of the heating zone of the heater, thereby increasing the non-uniformity of the temperature gradient G of the growth interface, which is more unfavorable for the regulation of the growth interface temperature gradient G and V / G, and is not conducive to the growth of high-quality single crystal silicon.

[0005] Based on the above, it is necessary to provide a single crystal silicon rod product, a single crystal growth device and a single crystal growth method to achieve the growth of defect-free single crystal silicon rod products.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0007] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a single crystal silicon rod product, a single crystal growth device and a single crystal growth method, so as to solve the problem in the prior art that in the process of growing single crystal silicon by the pulling method, the heating zone of the heater is fixed, making it difficult to control the temperature gradient G and V / G of the growth interface, thereby making it difficult to achieve the growth of defect-free single crystal silicon rod products.

[0008] In order to achieve the above-mentioned object and other related objects, the present invention provides a single crystal growth device, the single crystal growth device comprising:

[0009] A furnace body, wherein a seed crystal pulling mechanism is arranged on the top of the furnace body, and the seed crystal pulling mechanism comprises a seed crystal rope, a seed crystal chuck and a seed crystal, wherein the seed crystal rope passes through a through hole on the top of the furnace body and the seed crystal chuck is installed at the bottom end of the seed crystal rope, and the seed crystal is installed on the seed crystal chuck, and the bottom of the furnace body is provided with a base and a through hole is provided on the base;

[0010] A heat preservation chamber, wherein the heat preservation chamber is located inside the furnace body, and a heat preservation layer is provided on the bottom and side walls of the heat preservation chamber, and a heat preservation cover plate is provided on the top of the heat preservation chamber;

[0011] A crucible, fixed on the base and disposed in the heat preservation chamber, for carrying molten silicon;

[0012] A heater is disposed in the heat preservation chamber and outside the crucible, and is used to heat the crucible;

[0013] An insulating bracket, the insulating bracket is arranged inside the heater, the insulating bracket has a plurality of protrusions, the protrusions pass through the heater, and a short-circuit connection block is arranged on the protrusions exposed outside the heater, and the short-circuit connection block divides the heater into a heating area and a short-circuit area;

[0014] A support rod, one end of which is fixedly connected to the insulating bracket, and the other end of which is connected to a driving device, so that the insulating bracket moves up and down under the control of the driving device to change the area of ​​the heating zone of the heater;

[0015] A flow guide tube is arranged in the heat preservation chamber and connected to the heat preservation cover plate, and the flow guide tube extends from the outside of the crucible to the top of the molten silicon.

[0016] Optionally, the heater includes a plurality of blades, each of which is provided with a strip groove, and the number of the short-circuit connection blocks is equal to or less than the number of the blades, and when the number of the short-circuit connection blocks is equal to the number of the blades, the heating zone of the heater has the same height along the circumferential direction, and when the number of the short-circuit connection blocks is less than the number of the blades, the heating zone of the heater has different heights along the circumferential direction.

[0017] Optionally, the heater and the insulating support are both annular structures, and the insulating support is slidably connected to the strip groove.

[0018] Optionally, the height of the short-circuit connection block is 10 to 200 mm.

[0019] Optionally, the material of the short-circuit connection block includes a low-resistivity material, and the resistance of the material forming the short-circuit connection block is smaller than the resistance of the heater.

[0020] Optionally, the insulating support includes at least a silicon nitride insulating support, a silicon carbide insulating support or an aluminum nitride insulating support.

[0021] Optionally, the single crystal growth equipment also includes a crucible driving device, the support shaft of which passes through the insulation layer and the through holes on the base and is fixedly connected to the crucible, for driving the crucible to move upward at a preset rate during the single crystal growth process.

[0022] The present invention also provides a single crystal growth method, wherein during the single crystal growth process, the short-circuit connection block is moved up and down to change the length of the heating zone of the heater, thereby adjusting the heating area of ​​the heater during the single crystal growth process.

[0023] Optionally, during the silicon material melting stage of the single crystal growth process, the short-circuit connection block is moved to the bottom of the heater so that the length of the heating zone of the heater is maximized.

[0024] Optionally, the short-circuit connection block is moved up to a height position of 30% to 60% of the heater and then kept in a fixed position, thereby making the length of the heating zone become 40% to 70% of the length of the initial heating zone.

[0025] Optionally, during the growth of the single crystal, the crucible is moved upward at a preset rate and the rising rate of the short-circuit connection block is 0.1 to 0.9 times the rising rate of the crucible.

[0026] The present invention also provides a single crystal silicon rod product, which is obtained by using the above-mentioned single crystal production method, and the oxygen content of the single crystal silicon rod product is 3nppma to 20nppma.

[0027] As described above, the single crystal silicon rod product, single crystal growth equipment and single crystal growth method of the present invention have the following beneficial effects: the single crystal growth equipment of the present invention adds a short-circuit connection block to the insulating support, so that the supporting rod can be driven by a driving device when needed, so that the insulating support and the short-circuit connection block can slowly rise, thereby controlling the length of the heating zone of the heater, thereby enhancing the ability to regulate the temperature gradient distribution of the growth interface, improving the uniformity of the V / G of the growth interface, and promoting the growth of high-quality single crystal silicon rod products. In addition, the heating area of ​​the heater is adjusted by adjusting the length of the heating zone of the heater, which expands the application process window of the heater, so that the same heater can meet the production needs of single crystal silicon products with different oxygen contents such as logic devices, storage devices, and power devices, and the production of low-oxygen single crystal silicon rod products with an oxygen content of 3nppma to 20nppma is achieved through the single crystal growth method. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Shown is a schematic structural diagram of the single crystal growth equipment of the present invention.

[0029] Figure 2 Shown is a schematic diagram of the structure of a heater in a single crystal growth device using the present invention.

[0030] Figure 3 Shown is a schematic structural diagram of an insulating support and a short-circuit connection block in a single crystal growth device using the present invention.

[0031] Component number description

[0032] 10. Furnace body; 11. Seed crystal rope; 12. Seed crystal chuck; 13. Seed crystal; 14. Insulation chamber; 15. Crucible; 151. Inner crucible; 152. Outer crucible; 16. Heater; 161. Strip groove; 17. Insulation bracket; 171. Raised part; 18. Short-circuit connection block; 19. Support rod; 20. Drive device; 21. Insulation cover; 22. Guide tube; 23. Molten silicon; 24. Single crystal silicon rod; 25. Support shaft. DETAILED DESCRIPTION

[0033] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0034] For example, when describing the embodiments of the present invention in detail, for the sake of convenience, the schematic diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0035] For convenience of description, spatially relative terms such as "under", "below", "below", "below", "above", "on", etc. may be used herein to describe the relationship of one element or feature shown in the drawings to other elements or features. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0036] See also Figures 1 to 3 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and therefore the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0037] Example 1

[0038] like Figure 1As shown, the present invention provides a single crystal growth device, including a furnace body 10, a seed crystal 13 pulling mechanism is arranged on the top of the furnace body 10, and the seed crystal 13 pulling mechanism includes a seed crystal rope 11, a seed crystal chuck 12 and a seed crystal 13, wherein the seed crystal rope 11 passes through the through hole on the top of the furnace body 10 and the seed crystal chuck 12 is installed at the bottom end of the seed crystal rope 11, and the seed crystal 13 is installed on the seed crystal chuck 12, and the bottom of the furnace body 10 is provided with a base and a through hole is provided on the base; an insulation chamber 14, the insulation chamber 14 is located inside the furnace body 10, and an insulation layer is provided on the bottom and side walls of the insulation chamber 14, and an insulation cover plate 21 is provided on the top of the insulation chamber 14; a crucible 15, fixed on the base and arranged in the insulation chamber 14, for carrying molten silicon 23; a heater 16, arranged in the insulation chamber 14, located on the periphery of the crucible 15, for The crucible 15 is heated; an insulating bracket 17, the insulating bracket 17 is arranged inside the heater 16, the insulating bracket 17 has a plurality of protrusions 171, the protrusions 171 pass through the heater 16, and the protrusions 171 exposed outside the heater 16 are provided with short-circuit connection blocks 18, the short-circuit connection block 18 divides the heater 16 into a heating zone and a short-circuit zone; a support rod 19, one end of the support rod 19 is fixedly connected to the insulating bracket 17, and the other end of the support rod 19 is connected to a driving device 20, so that the insulating bracket 17 moves up and down under the control of the driving device 20 to change the area of ​​the heating zone of the heater 16; a guide tube 22, the guide tube 22 is arranged in the insulation chamber 14, connected to the insulation cover plate 21, and the guide tube 22 extends from the outside of the crucible 15 to above the molten silicon 23. The single crystal growth equipment of the present invention adds a short-circuit connection block 18 to the heater 16, so as to change the length of the heating zone on the heater 16 by adjusting the height of the short-circuit connection block 18 when necessary, thereby enhancing the ability to regulate the temperature gradient distribution of the growth interface, improving the uniformity of V / G of the growth interface, and being more conducive to ensuring the stability and consistency of the quality of single crystal silicon production.

[0039] Specifically, refer to Figure 1 After the polycrystalline silicon raw material is placed in the crucible 15, the polycrystalline silicon raw material in the crucible 15, which is usually in a solid state at the beginning, is melted by a heater 16 in the single crystal furnace to form molten silicon 23, and then a seed crystal 13 fixed on a seed crystal chuck 12 is inserted into the surface of the molten silicon 23. After the seed crystal 13 and the molten silicon 23 are fully melted, the seed crystal 13 pulling mechanism is used to drive the seed crystal rope 11 to pull the seed crystal 13 up and down, so that the single crystal silicon rod 24 grows at the lower end of the seed crystal 13. This is an existing common technology and will not be described in detail here.

[0040] Specifically, refer to Figure 1The top of the insulation chamber 14 is open upward, and an insulation layer is provided on the bottom and side walls of the insulation chamber 14. An insulation cover plate 21, such as a graphite insulation cover plate 21, is provided on the top of the insulation chamber 14. The single crystal furnace also includes a guide tube 22, which extends from the outside of the crucible 15 to the top of the molten silicon 23. The guide tube 22 is located at the top of the insulation chamber 14 and is connected to the insulation cover plate 21. The material of the insulation layer can be one or more of graphite felt or carbon-carbon composite materials. For example, the material of the insulation layer can be graphite felt. Through the joint effect of the insulation layer and the insulation cover plate 21, the influence of the temperature generated by the heater 16 on the furnace body 10 can be reduced, thereby stabilizing the thermal field and reducing heat loss, so as to ensure the quality and shape of the single crystal silicon rods 24 in the furnace body 10.

[0041] refer to Figure 1 In this embodiment, the crucible 15 generally includes an inner crucible 151 and an outer crucible 152. The inner crucible 151 is used to contain the molten silicon 23, and the outer crucible 152 is wrapped around the outer side of the inner crucible 151. The material of the inner crucible 151 and / or the outer crucible 152 can be one or more of graphite, quartz, or a carbon-carbon composite material. For example, the material of the inner crucible 151 can be quartz, and the material of the outer crucible 152 can be graphite.

[0042] refer to Figure 1 The heater 16 is disposed in the heat preservation chamber 14, and the heater 16 is disposed between the heat preservation layer and the outer periphery of the crucible 15. Specifically, a side heater 16 may be disposed on the periphery of the graphite crucible 15 to fully heat the polysilicon raw material placed in the quartz crucible 15 to melt it quickly to form molten silicon 23. In other embodiments, a bottom heater 16 may also be disposed at the bottom of the graphite crucible 15, wherein the side heater 16 and the bottom heater 16 are independent of each other, and the polysilicon raw material may be heated separately to melt it.

[0043] As an example, the heater 16 is an annular structure, and the heater 16 includes a plurality of blades, and strip grooves are formed on the blades.

[0044] Specifically, refer to Figure 2 The blade is provided with a strip groove, and the strip groove has two forms of opening upward and opening downward, and there is a blade between two adjacent strip grooves with the same opening direction. The heater 16 includes a plurality of blades, and an insulating bracket 17 is arranged inside the heater 16 so that the current path generated by the heater 16 is distributed in an S shape in a single blade.

[0045] As an example, the number of the short-circuit connection blocks 18 is equal to or less than the number of the blades, and when the number of the short-circuit connection blocks 18 is equal to the number of the blades, the heating zone of the heater 16 has the same height along the circumferential direction, and when the number of the short-circuit connection blocks 18 is less than the number of the blades, the heating zone of the heater 16 has different heights along the circumferential direction.

[0046] Specifically, Figure 2 As shown, the insulating bracket 17 has a plurality of protrusions 171, and the protrusions 171 pass through the strip grooves of the heater 16. The insulating bracket 17 is slidably connected to the strip grooves so that the insulating bracket 17 can move up and down along the strip grooves. The protrusions 171 exposed outside the heater 16 are provided with short-circuit connection blocks 18. The current path generated by the heater 16 flows through the short-circuit connection blocks 18, thereby dividing the heater 16 into a heating area and a short-circuit area. The area above the short-circuit connection block 18 is the area where the current flows, i.e., the heating area. According to the "skin effect" of the current, the current in the heater 16 will preferentially pass through the short-circuit connection block 18, and the area below the short-circuit connection block 18 will be short-circuited and lose the resistance heating efficiency, forming a short-circuit area. Figure 3 As shown, a support rod 19 is also fixedly connected to the insulating bracket 17, and the other end of the support rod 19 is connected to a driving device 20. The driving device 20 is arranged below the furnace body 10 and is located outside the furnace body 10. The support rod 19 is driven by the driving device 20 to make the insulating bracket 17 and the short-circuit connection block 18 rise slowly, so that the isothermal zone in the center of the heating zone of the heater 16 moves upward and is closer to the growth interface of the single crystal silicon rod 24, which is beneficial to improve the consistency of the temperature gradient of the growth interface and improve the uniformity of the V / G of the growth interface, so as to obtain a flatter growth interface morphology.

[0047] like Figure 2 As shown, the insulating bracket 17 is also an annular structure and is nested inside the heater 16. When the number of the short-circuit connection blocks 18 is equal to the number of the blades, the heating zone of the heater 16 has the same height along the circumference to form a uniform thermal field environment, meeting the needs of specific products for uniform circumferential thermal field conditions; when the number of the short-circuit connection blocks 18 is less than the number of the blades, the heating zone of the heater 16 has different heights along the circumference to form a non-uniform thermal field environment around the crucible 15. On the one hand, by locally adjusting the heating zone area of ​​the heater 16, the ability to adjust the oxygen content in the single crystal silicon rod 24 is enhanced. On the other hand, it can compensate for the asymmetric distribution of the liquid surface temperature of the molten silicon 23 caused by the horizontal magnetic field, non-circularly symmetrical thermal field components, etc., and improve the stability of the growth process of the single crystal silicon rod 24.

[0048] As an example, the height of the short-circuit connection block 18 is 10-200 mm.

[0049] As an example, the material of the short-circuit connection block 18 includes a low-resistivity material, and the resistance of the material forming the short-circuit connection block 18 is lower than the resistance of the heater 16 .

[0050] Specifically, the height of the short-circuit connection block 18 is 10 to 200 mm. For example, the height of the short-circuit connection block 18 is 10 mm, 30 mm, 90 mm, 150 mm or 200 mm. By setting short-circuit connection blocks 18 of different heights, the length of the heating zone of the heater 16 at the start of crystal growth can be controlled. During the growth of the single crystal silicon rod 24, the length of the heating zone of the heater 16 has an important influence on the oxygen content in the molten silicon 23 and the single crystal silicon rod 24. Further, according to the "skin effect" of the current, the current in the heater 16 will preferentially pass through the low resistivity material. Therefore, the material forming the short-circuit connection block 18 includes a low resistivity material and the resistance of the material forming the short-circuit connection block 18 is less than the resistance of the heater 16, so that the area below the short-circuit connection block 18 is short-circuited and loses the resistance heating efficiency, forming a short-circuit zone.

[0051] As an example, the insulating support 17 includes at least one of a silicon nitride insulating support 17 , a silicon carbide insulating support 17 or an aluminum nitride insulating support 17 .

[0052] Specifically, in this embodiment, an insulating contact is formed between the insulating support 17 and the heater 16, wherein the insulating support 17 includes at least one of a silicon nitride insulating support 17, a silicon carbide insulating support 17 or an aluminum nitride insulating support 17, for example, the insulating support 17 can be a silicon nitride insulating support 17.

[0053] As an example, the single crystal growth equipment also includes a crucible driving device, whose support shaft 25 passes through the insulation layer and the through holes on the base and is fixedly connected to the crucible 15, and is used to drive the crucible 15 to move upward at a preset rate during the single crystal growth process.

[0054] Specifically, Figure 1 As shown, a crucible driving device is also provided below the furnace body 10, wherein the support shaft 25 of the crucible driving device passes through the through holes on the insulation layer and the base and is fixedly connected to the bottom of the crucible 15, and is used to drive the crucible 15 to move upward at a preset constant speed during the single crystal growth process, and after the growth of the single crystal silicon rod 24 of the required length is completed, the crucible 15 can also be driven down to separate the single crystal silicon rod 24 from the upper surface of the molten silicon 23. In order to accurately control the lifting speed of the crucible 15 and the short-circuit connection block 18, the above-mentioned crucible driving device and the driving device 20 of the support rod 19 need to have better control accuracy.

[0055] Example 2

[0056] The present invention also provides a single crystal growth method, which can be performed according to any of the single crystal growth devices described above. Therefore, please refer to the above content for the introduction of the single crystal growth device, which will not be repeated here for the purpose of brevity. In addition, during the growth of the single crystal silicon rod 24, the length of the heating zone of the heater 16 has an important influence on the oxygen content in the molten silicon 23 and the single crystal silicon rod 24. Generally, the shorter the length of the heating zone of the heater 16, the shorter the high temperature zone of the inner wall of the inner crucible 151, and the lower the oxygen concentration entering the molten silicon 23 when the single crystal silicon rod 24 grows, so that the oxygen content of the grown single crystal silicon rod 24 is also lower.

[0057] When the single crystal growth device is used for single crystal growth, the length of the heating zone of the heater 16 is changed by continuously moving the short-circuit connection block 18, thereby achieving high-quality growth of the single crystal silicon rod 24 product. Specifically, during the single crystal growth process, in the silicon material melting stage, the short-circuit connection block 18 is first moved to the bottom of the heater 16 so that the area of ​​the heating zone of the heater 16 is maximized, and then the driver is started to drive the support rod 19 to further drive the insulating bracket 17 and drive the short-circuit connection block 18 to move upward, thereby changing the length of the heating zone of the heater 16, thereby adjusting the heating zone area of ​​the heater 16 during the single crystal growth process, which is conducive to growing high-quality single crystal silicon rod 24 products.

[0058] As an example, the crucible 15 moves upward at a preset rate and the rising rate of the short-circuit connection block 18 is 0.1 to 0.9 times the rising rate of the crucible 15. Of course, it should be noted that, according to the growth requirements of single crystal silicon rod 24 products with different oxygen contents, the rising rate of the short-circuit connection block 18 is 0.1 to 0.9 times the rising rate of the crucible 15. And as an example, during the single crystal growth process, the crucible 15 moves upward at a preset constant speed. Compared with the prior art in which the heating zone of the heater 16 remains unchanged to grow the single crystal silicon rod 24 product, the ratio of the growth interface height difference to the diameter is less than 5%, that is, the single crystal silicon rod 24 can maintain a nearly flat growth interface from beginning to end, which is more conducive to the growth of high-quality single crystal silicon rod 24 products.

[0059] As an example, the short-circuit connection block is moved up to a height position of 30% to 60% of the heater and then kept in a fixed position, thereby making the length of the heating zone become 40% to 70% of the length of the initial heating zone.

[0060] Specifically, during the single crystal growth process, the static working mode of the single crystal growth equipment can also be used, that is, the position of the short-circuit connection block 18 is moved up once and then remains fixed, so as to achieve the growth of the single crystal silicon rod 24 product with low oxygen content. In the silicon material melting stage, the short-circuit connection block 18 is first moved to the bottom of the heater 16 so that the area of ​​the heating zone of the heater 16 is the largest, and then the short-circuit connection block 18 is moved up to a position of 30% to 60% of the starting height of the heater 16 and then remains fixed, so that the area of ​​the heating zone of the heater 16 during the single crystal growth process is adjusted to 40% to 70% of the starting area. According to the single crystal growth equipment and single crystal growth method with adjustable length of the heating zone of the heater 16 of the present invention, different single crystal growth methods can be selected according to the needs of product categories to grow single crystal silicon rods 24 products with an oxygen content of 3nppma to 20nppma, and when the required product oxygen content is determined, during the growth process of the single crystal silicon rod 24, a method of moving and short-circuiting the connecting block to adjust the length of the heating zone is selected, so that the oxygen content of the head and tail of the single crystal silicon rod 24 can be uniform and the difference is less than 1nppma.

[0061] In summary, the present invention provides a single crystal silicon rod product, a single crystal growth device and a single crystal growth method. The single crystal growth device includes a furnace body, a crucible, a heater, an insulating support, a support rod, a short-circuit connection block and a driving device, wherein the heater is divided into a heating zone and a short-circuit zone by the short-circuit connection block. During the crystal growth process, as the crucible moves upward, the driving device is used to drive the support rod so that the insulating support and the short-circuit connection block slowly rise, thereby controlling the length of the heating zone of the heater, thereby enhancing the ability to regulate the temperature gradient distribution of the growth interface, improving the uniformity of the V / G of the growth interface, and promoting the growth of high-quality single crystal silicon rod products. In addition, the heating area of ​​the heater is adjusted by adjusting the length of the heating zone of the heater, expanding the application process window of the heater, so that the same heater can meet the production of single crystal silicon rod products with different oxygen contents such as logic devices, storage devices, and power devices, and the single crystal growth method realizes the production of single crystal silicon rod products with low oxygen content of 3nppma to 20nppma.

[0062] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A single crystal growth device, characterized in that: include: A furnace body, wherein a seed crystal pulling mechanism is arranged on the top of the furnace body, and the seed crystal pulling mechanism comprises a seed crystal rope, a seed crystal chuck and a seed crystal, wherein the seed crystal rope passes through a through hole on the top of the furnace body and the seed crystal chuck is installed at the bottom end of the seed crystal rope, and the seed crystal is installed on the seed crystal chuck, and the bottom of the furnace body is provided with a base and a through hole is provided on the base; A heat preservation chamber, wherein the heat preservation chamber is located inside the furnace body, and a heat preservation layer is provided on the bottom and side walls of the heat preservation chamber, and a heat preservation cover plate is provided on the top of the heat preservation chamber; A crucible, fixed on the base and disposed in the heat preservation chamber, for carrying molten silicon; A heater is disposed in the heat preservation chamber and outside the crucible, and is used to heat the crucible; An insulating bracket, the insulating bracket is arranged inside the heater, the insulating bracket has a plurality of protrusions, the protrusions pass through the heater, and a short-circuit connection block is arranged on the protrusions exposed outside the heater, and the short-circuit connection block divides the heater into a heating area and a short-circuit area; A support rod, one end of which is fixedly connected to the insulating bracket, and the other end of which is connected to a driving device, so that the insulating bracket moves up and down under the control of the driving device to change the area of ​​the heating zone of the heater; A flow guide tube is arranged in the heat preservation chamber and connected to the heat preservation cover plate, and the flow guide tube extends from the outside of the crucible to the top of the molten silicon.

2. The single crystal growth device according to claim 1, characterized in that: The heater includes a plurality of blades, each of which is provided with a strip groove, and the number of the short-circuit connection blocks is equal to or less than the number of the blades. When the number of the short-circuit connection blocks is equal to the number of the blades, the heating zone of the heater has the same height along the circumferential direction, and when the number of the short-circuit connection blocks is less than the number of the blades, the heating zone of the heater has different heights along the circumferential direction.

3. The single crystal growth device according to claim 2, characterized in that: The heater and the insulating support are both annular structures, and the insulating support is slidably connected to the strip groove.

4. The single crystal growth equipment according to claim 1, characterized in that: The height of the short-circuit connection block is 10 to 200 mm.

5. The single crystal growth device according to claim 1, characterized in that: The material of the short-circuit connection block includes a low-resistivity material, and the resistance of the material forming the short-circuit connection block is lower than the resistance of the heater.

6. The single crystal growth device according to claim 1, characterized in that: The insulating support at least includes a silicon nitride insulating support, a silicon carbide insulating support or an aluminum nitride insulating support.

7. The single crystal growth equipment according to claim 1, characterized in that: The single crystal growth equipment also includes a crucible driving device, the support shaft of which passes through the insulation layer and the through holes on the base and is fixedly connected to the crucible, and is used to drive the crucible to move upward at a preset rate during the single crystal growth process.

8. A single crystal growth method, characterized in that: In the single crystal growth method, during the single crystal growth process, the short-circuit connection block is moved up and down to change the length of the heating zone of the heater, thereby adjusting the heating area of ​​the heater during the single crystal growth process.

9. The single crystal growth method according to claim 8, characterized in that: During the silicon material melting stage of the single crystal growth process, the short-circuit connection block is moved to the bottom of the heater so that the heating zone length of the heater is maximized.

10. The single crystal growth method according to claim 9, characterized in that: The short-circuit connection block is moved up to a height position of 30% to 60% of the heater and then kept in a fixed position, thereby making the length of the heating zone become 40% to 70% of the length of the initial heating zone.

11. The single crystal growth method according to claim 8, characterized in that: During the growth of the single crystal, the crucible is moved upward at a preset rate and the rising rate of the short-circuit connection block is 0.1 to 0.9 times the rising rate of the crucible.

12. A single crystal silicon rod product, wherein the single crystal silicon rod product is obtained by the single crystal production method according to any one of claims 8 to 11, and the oxygen content of the single crystal silicon rod product is 3nppma to 20nppma.

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