Method for regulating steady flow of inert gas, method for manufacturing single crystal silicon, and single crystal silicon

Abstract

The present invention provides a method for regulating the steady flow of an inert gas, a method for manufacturing a single crystal silicon, and a single crystal silicon, which are applied to a crystal pulling furnace. The regulation method includes: introducing an inert gas from the auxiliary furnace chamber of the crystal pulling furnace into the crystal pulling furnace, and regulating the flow direction of the inert gas introduced into the auxiliary furnace chamber of the crystal pulling furnace. According to the steady flow device of the present invention, the flow direction of the inert gas can be restricted, the swing amplitude of the single crystal silicon rod can be reduced, the probability of the occurrence of single crystal growth dislocation phenomena can be decreased, and the contamination and erosion of the crystal rod and the side wall of the thermal field components caused by impurities can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a method for regulating the steady flow of an inert gas, a method for manufacturing single crystal silicon, and single crystal silicon. Background Art

[0002] The Magnetic Field Applied Czochralski Method (MCZ) is currently the most common crystal pulling method. It is popularized for suppressing the thermal convection of polycrystalline silicon melt during crystal growth. It can also be used as a way to reduce the oxygen content in single crystal silicon rods.

[0003] In the prior art, a single crystal silicon rod is manufactured by using a crystal pulling furnace. The polycrystalline silicon raw material is melted in a quartz crucible in the crystal pulling furnace. When the polycrystalline silicon raw material is molten, the quartz crucible will undergo the following reactions: SiO 2 (s)→Si(l)+2O, the oxygen atoms generated by the quartz crucible wall are stirred by natural convection and evenly distributed in the silicon solution, and some oxygen atoms on the surface of the silicon solution will undergo the following reaction: Si(l)+O→SiO(g), and evaporate in the form of silicon monoxide (SiO). In order to control the impurities in the crystal pulling furnace, it is necessary to evacuate the furnace and introduce argon. As a protective gas, argon is fed in from the top of the auxiliary furnace chamber, and devices such as guide tubes are set in the main furnace chamber to adjust the flow direction and speed of argon and improve the oxide transmission direction in the crystal pulling furnace. However, when argon is introduced into the auxiliary furnace chamber of the crystal pulling furnace, since the speed of argon in the furnace ranges from 0.9m / s to 8.0m / s, there is more overall turbulence in the auxiliary furnace chamber. Due to the long traction rope and the initial stage of single crystal silicon rod pulling, it is easy to cause shaking, which is not conducive to stable contact of the crystal growth interface and is very likely to cause crystal dislocation, increase the number of crystal rod remelting times, and increase costs. In addition, the traditional guide tube will also cause more turbulence in the main furnace chamber, which is not conducive to the discharge of impurities and causes impurities to stick to the side walls of the hot field components. Summary of the invention

[0004] In view of this, the present invention provides a method for regulating the steady flow of an inert gas. By installing the steady flow device in the auxiliary furnace chamber of a crystal pulling furnace, the flow direction of the inert gas entering the auxiliary furnace chamber can be adjusted to solve the problem that the single crystal silicon rod is prone to shaking in the early stage of growth due to excessive gas turbulence in the auxiliary furnace chamber, which in turn leads to unstable contact between the crystal growth interface and the melt surface and easy dislocation of the crystal.

[0005] In order to solve the above technical problems, the present invention provides a method for regulating the steady flow of an inert gas.

[0006] The method for regulating the steady flow of an inert gas according to the first aspect of the present invention is applied to a crystal pulling furnace, and the regulating method comprises:

[0007] Introduce an inert gas from the auxiliary furnace chamber of the crystal pulling furnace into the crystal pulling furnace, and adjust the flow direction of the inert gas introduced into the auxiliary furnace chamber of the crystal pulling furnace.

[0008] Preferably, the method for regulating the steady flow of the inert gas includes:

[0009] Rectify the inert gas in the auxiliary furnace chamber;

[0010] Uniformly divide the rectified inert gas.

[0011] Preferably, the method for regulating the steady flow of the inert gas further includes:

[0012] Rectify the inert gas after division again;

[0013] Divide the inert gas after rectification again.

[0014] Preferably, in the method for regulating the steady flow of the inert gas, a steady flow interval is formed between gas rectification and division, and the method further includes:

[0015] Adjust the size of the steady flow interval to adjust the flow direction and flow rate of the gas flow.

[0016] Preferably, the method for regulating the steady flow of the inert gas further includes:

[0017] Control the height of the inert gas when it is divided in the auxiliary furnace chamber to adapt to the growth of crystal rods of different lengths.

[0018] According to the method for manufacturing single crystal silicon according to the second aspect embodiment of the present invention, which is applied to a crystal pulling furnace, the crystal pulling furnace includes a main furnace chamber and an auxiliary furnace chamber, and the manufacturing method includes:

[0019] Melt polysilicon in the main furnace chamber of the crystal pulling furnace;

[0020] Bring the seed crystal into contact with the molten polysilicon phase;

[0021] Introduce an inert gas into the auxiliary furnace chamber of the crystal pulling furnace and perform steady flow on the inert gas. The method for steady flow of the inert gas includes the method for regulating the steady flow of the inert gas as described in the above embodiments.

[0022] Preferably, the manufacturing method further includes:

[0023] After the polysilicon raw material is completely melted, bring the seed crystal into contact with the molten polysilicon phase, and when the length of the crystal rod growth has not reached the bottom of the auxiliary furnace chamber, adjust the size of the steady flow interval to adjust the flow direction and flow rate of the gas flow.

[0024] Preferably, the manufacturing method further includes;

[0025] Control the height of the inert gas during its diversion in the secondary furnace chamber to adapt to the growth of single crystal rods of different lengths.

[0026] Preferably, a flow guide cylinder is further provided in the main furnace chamber of the crystal pulling furnace, and the manufacturing method further includes:

[0027] When the inert gas flows into the main furnace chamber, guide the inert gas through the flow guide cylinder so that the inert gas flows to the contact surface between the polysilicon melt and the seed crystal.

[0028] The single crystal silicon according to the embodiment of the third aspect of the present invention is obtained by the manufacturing method of the single crystal silicon as described in the above embodiment.

[0029] The beneficial effects of the above technical solutions of the present invention are as follows:

[0030] 1) According to the inert gas steady flow regulation method of the embodiment of the present invention, the flow direction of the inert gas introduced into the secondary furnace chamber of the crystal pulling furnace can be sorted out to reduce the turbulence intensity of the inert gas inside the secondary furnace chamber of the crystal pulling furnace. By restricting the flow direction of the inert gas, the swing of the single crystal silicon rod caused by the gas flow is reduced, which helps the stable contact between the single crystal silicon rod and the molten liquid surface, and reduces the probability of phenomena such as single crystal growth dislocations. At the same time, the impurities in the main furnace chamber are prevented from being carried to the secondary furnace chamber by the turbulent flow, thus avoiding the pollution and erosion of the crystal rod and the side wall of the thermal field components;

[0031] 2) By adjusting the steady flow interval through the spacing, the single crystal growth environment in the main furnace chamber is further improved, the occurrence of turbulent flow is suppressed, and the probability of crystal remelting is reduced;

[0032] 3) It can adapt to the growth of single crystal rods of different lengths. Description of the Drawings

[0033] Figure 1a It is a front view of a structure of the steady flow device of the present invention;

[0034] Figure 1b It is a top view of the steady flow device in FIG. 1;

[0035] Figure 1c It is a front view of another structure of the steady flow device of the present invention;

[0036] Figure 1d For Figure 1c The top view of the steady flow device in;

[0037] Figure 1e It is a front view of yet another structure of the steady flow device of the present invention;

[0038] Figure 1f For Figure 1e The top view of the steady flow device in;

[0039] Figure 1g Front view of another structure of the flow stabilizing device of the present invention;

[0040] Figure 2a Schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0041] Figure 2b Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0042] Figure 2c Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0043] Figure 2d Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0044] Figure 2e Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0045] Figure 2f Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0046] Figure 2g Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0047] Figure 2h Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0048] Figure 2i Another schematic diagram of a structure of the first flow stabilizing cover and the second flow stabilizing cover of the present invention;

[0049] Figure 3a Schematic diagram of a structure of the transmission component of the present invention;

[0050] Figure 3b Another schematic diagram of a structure of the transmission component of the present invention;

[0051] Figure 3c Another schematic diagram of a structure of the transmission component of the present invention;

[0052] Figure 3d Another schematic diagram of a structure of the transmission component of the present invention;

[0053] Figure 4 Diagram of the gas flow state in a crystal pulling furnace of the present invention;

[0054] Figure 5 Diagram of the gas flow state in another crystal pulling furnace of the present invention.

[0055] Reference numerals

[0056] Steady flow device 100;

[0057] First steady flow cover 110; First through hole 111;

[0058] Second steady flow cover 120; Second through hole 121;

[0059] Spacing adjustment mechanism 130; Spacing adjustment bracket 131; First drive mechanism 132; Transmission component 133;

[0060] Height adjustment mechanism 140;

[0061] Crystal pulling furnace 200;

[0062] Furnace body 210; Main furnace chamber 211; Auxiliary furnace chamber 212; Flow guide cylinder 213;

[0063] Inert gas 300;

[0064] Impurity 400. Specific implementation mode

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention.

[0066] First, the steady flow device 100 according to the embodiments of the present invention will be specifically described below in conjunction with the accompanying drawings.

[0067] As Figures 1a to 5 shown, the steady flow device 100 according to the embodiments of the present invention is applied to the crystal pulling furnace 200 and includes a first steady flow cover 110 and a second steady flow cover 120.

[0068] Specifically, a plurality of first through holes 111 are provided on the first steady flow cover 110. The first steady flow cover 110 is used to be installed in the auxiliary furnace chamber 212 of the crystal pulling furnace 200 to adjust the flow direction of the inert gas 300 introduced into the crystal pulling furnace 200; a plurality of second through holes 121 are provided on the second steady flow cover 120. The second steady flow cover 120 is used to be installed in the auxiliary furnace chamber 212 of the crystal pulling furnace 200 and is arranged opposite to the first steady flow cover 110 to adjust the flow direction of the inert gas 300 adjusted by the first steady flow cover 110.

[0069] That is to say, after the inert gas 300 is introduced into the secondary furnace chamber 212 of the crystal pulling furnace 200, the inert gas 300 first passes through the first through hole 111 of the first flow stabilizer 110, and its flow direction is straightened, changing from the original turbulent flow to a vertically downward flow direction, thereby reducing the air flow disorder phenomenon of the inert gas 300. Subsequently, the air flow flows out from the second through hole 121 of the second flow stabilizer 120 and is straightened here to form a more stable and orderly air flow. When the straightened gas flows through the surface of the single crystal silicon rod in the main furnace chamber 211, the swinging amplitude of the single crystal silicon rod affected by the air flow can be reduced, which helps the stable contact between the single crystal silicon rod and the molten liquid surface, reduces the occurrence probability of phenomena such as single crystal growth dislocation, and improves the production efficiency of the single crystal silicon rod. At the same time, due to the uniform and stable flow of the air flow, the impurities 400 in the main furnace chamber 211 can be prevented from being carried to the secondary furnace chamber 212 by the turbulent flow, which is beneficial to the discharge of the impurities 400 and avoids problems such as pollution and erosion of the crystal rod and the side wall of the hot field components caused by the impurities 400.

[0070] Therefore, the flow stabilizer 100 according to the embodiment of the present invention can straighten the flow direction of the inert gas 300 introduced into the secondary furnace chamber 212 of the crystal pulling furnace 200, make the gas flow direction more orderly, reduce the turbulence intensity of the inert gas 300 inside the secondary furnace chamber 212 of the crystal pulling furnace 200, restrict the flow direction of the inert gas 300, reduce the swing of the single crystal silicon rod caused by the air flow, help the stable contact between the single crystal silicon rod and the molten liquid surface, reduce the occurrence probability of phenomena such as single crystal growth dislocation, improve the production efficiency of the single crystal silicon rod, prevent the impurities 400 in the main furnace chamber 211 from being carried to the secondary furnace chamber 212 by the turbulent flow, and avoid problems such as pollution and erosion of the crystal rod and the side wall of the hot field components caused by the impurities 400.

[0071] Preferably, as Figure 1c 、 Figure 4 and Figure 5 shown, the first flow stabilizer 110 is formed in a funnel shape with a wide mouth at one end and a narrow mouth at the other end. The first flow stabilizer 110 is used to rectify the inert gas 300 introduced into the crystal pulling furnace 200. The inert gas 300 flows in from the wide mouth end of the first flow stabilizer 110 and flows out from the narrow mouth end. The second flow stabilizer 120 is formed in a funnel shape with a wide mouth at one end and a narrow mouth at the other end. The narrow mouth end of the second flow stabilizer 120 is disposed opposite to the narrow mouth end of the first flow stabilizer 110. The second flow stabilizer 120 is used to evenly distribute the rectified inert gas 300.

[0072] That is to say, both the first flow stabilizer 110 and the second flow stabilizer 120 are funnel-shaped, that is, one end is a wide opening and the other end is a narrow opening. The narrow opening ends of the first flow stabilizer 110 and the second flow stabilizer 120 are arranged adjacent to each other. During flow stabilization, the inert gas 300 first flows into the first flow stabilizer 110 from the wide opening end and flows out from the narrow opening end. After passing through the first through hole 111, the flow direction of the inert gas 300 is combed and rectified, reducing the air flow disorder phenomenon of the inert gas 300. Subsequently, the air flow flows into the second flow stabilizer 120 from the narrow opening end and flows out from the wide opening end. After the rectified air flow is evenly divided through the second through hole 121, a more stable and orderly air flow is formed, further reducing the swing amplitude of the single crystal silicon rod affected by the air flow, reducing the occurrence probability of single crystal growth dislocations and other phenomena, further improving the production efficiency of the single crystal silicon rod, being more conducive to the discharge of impurities 400, and better protecting the crystal rod and the thermal field components.

[0073] Among them, the shapes of the first flow stabilizer 110 and the second flow stabilizer 120 in the present invention are not limited to this. In other embodiments of the present invention, flow stabilizers of other shapes, such as conical shapes, can also be used, and can be designed according to the shape of the secondary furnace chamber 212 of the crystal pulling furnace, and the shapes of the first flow stabilizer 110 and the second flow stabilizer 120 can also be different.

[0074] The inert gas 300 in the present invention can preferably be argon, and argon has good stability as a protective gas.

[0075] According to an embodiment of the present invention, the flow stabilization device 100 further includes a spacing adjustment mechanism 130 for adjusting the distance between the first flow stabilizer 110 and the second flow stabilizer 120 to expand the flow stabilization interval.

[0076] In other words, the first flow stabilizer 110 and the second flow stabilizer 120 are connected by the spacing adjustment mechanism 130. The spacing adjustment mechanism 130 can adjust the distance between the first flow stabilizer 110 and the second flow stabilizer 120, so that the air flow passing through the first flow stabilizer 110 flows to the second flow stabilizer 120 after passing through a longer flow stabilization interval, further stabilizing the flow rate of the gas. The air flow is more stable and orderly after passing through the second flow stabilizer 120, so as to further improve the growth environment of the single crystal silicon rod in the main furnace chamber 211.

[0077] Preferably, the spacing adjustment mechanism 130 includes a spacing adjustment bracket 131 and a first driving mechanism 132. The spacing adjustment bracket 131 is respectively connected to the first flow stabilizer 110 and the second flow stabilizer 120, or the spacing adjustment bracket 131 is connected to the first flow stabilizer 110 or the second flow stabilizer 120. The first driving mechanism 132 is connected to the spacing adjustment bracket 131 for driving the spacing adjustment bracket 131 to drive the first flow stabilizer 110 and the second flow stabilizer 120 to approach or move away from each other.

[0078] That is to say, the first flow stabilizer 110 and the second flow stabilizer 120 can be respectively connected to the spacing adjustment bracket 131, or the first flow stabilizer can be connected to the spacing adjustment bracket, or the second flow stabilizer 120 can be connected to the spacing adjustment bracket 131. When the spacing adjustment bracket 131 is connected to the first flow stabilizer 110 and the second flow stabilizer 120, the first driving mechanism 132 can drive the spacing adjustment bracket 131 to drive the first flow stabilizer 110 and the second flow stabilizer 120 to approach or move away from each other, thereby adjusting the distance between the first flow stabilizer 110 and the second flow stabilizer 120. This distance can effectively improve the flow stabilization effect of the air flow, causing the air flow to adjust its direction again after passing through this spacing, which not only facilitates the control of the flow rate but also better regulates the flow direction of the air flow. It is also possible to use the spacing adjustment bracket 131 to be connected to the first flow stabilizer 110 while the second flow stabilizer 120 is fixed, or the first flow stabilizer 110 is fixed and the spacing adjustment bracket 131 is connected to the second flow stabilizer 120, and the distance between the first flow stabilizer 110 and the second flow stabilizer 120 is adjusted by driving the first flow stabilizer 110 or the second flow stabilizer 120.

[0079] Preferably, the first driving mechanism 132 is connected to the spacing adjustment bracket 131 through a transmission member 133, and the transmission member 133 includes a transmission belt or a transmission chain.

[0080] As Figures 3a to 3d shown, the first driving mechanism 132 and the spacing adjustment bracket 131 can be connected through a transmission belt or a transmission chain. The transmission belt can be in the transmission mode of a gear and a conveyor belt, or in the transmission mode of a transmission chain and a gear. This structure has a good transmission effect and moves relatively smoothly. Of course, in other embodiments of the present invention, other structures can also be used to achieve the first driving mechanism 132 driving the spacing adjustment bracket 131 to move, and further achieve the first driving mechanism 132 driving the first flow stabilizer 110 or the second flow stabilizer 120 to move. Among them, the first driving mechanism 132 can use an electric motor. A cylinder or other driving methods can also be used, which are not limited herein.

[0081] According to another embodiment of the present invention, the flow stabilization device 100 further includes a height adjustment mechanism 140. The height adjustment mechanism 140 is connected to the spacing adjustment mechanism 130 and is used to drive the spacing adjustment mechanism 130 to move to adjust the heights of the first flow stabilizer 110 and the second flow stabilizer 120 in the secondary furnace chamber 212 of the crystal pulling furnace 200.

[0082] As Figure 5 shown, the height adjustment mechanism 140 is connected to the spacing adjustment mechanism 130. The height adjustment mechanism 140 can drive the spacing adjustment mechanism 130 to move up and down to adjust the heights of the first flow stabilizer 110 and the second flow stabilizer 120 in the secondary furnace chamber 212 of the crystal pulling furnace, thereby enabling the crystal pulling furnace to adapt to growing crystal rods of different lengths and improving the flexibility of use of the crystal pulling furnace.

[0083] Preferably, the height adjustment mechanism 140 and the spacing adjustment mechanism 130 can also be connected by a transmission component 133. For the specific structure, reference can be made to the transmission component 133 in the above embodiments, which will not be elaborated here.

[0084] According to some embodiments of the present invention, each first flow stabilizer cover 110 and each second flow stabilizer cover 120 form a group, and the flow stabilizer device 100 includes multiple groups of first flow stabilizer covers 110 and second flow stabilizer covers 120.

[0085] As Figures 1e to 1g shown, the flow stabilizer device 100 includes a combination of multiple groups of first flow stabilizer covers 110 and second flow stabilizer covers 120. That is to say, when in use, a combination of a group of first flow stabilizer covers 110 and second flow stabilizer covers 120 can be arranged in the secondary furnace chamber 212 of the crystal pulling furnace according to actual conditions, or it can also be a combination of multiple groups of first flow stabilizer covers 110 and second flow stabilizer covers 120. In this way, the flow direction and flow rate of the inert gas 300 in the secondary furnace chamber 212 of the crystal pulling furnace can be better adjusted under appropriate circumstances, further improving the flexibility of use of the flow stabilizer device 100.

[0086] Optionally, the opening ratio of the first flow stabilizer cover 110 and the second flow stabilizer cover 120 is 80% - 95%.

[0087] That is to say, the opening ratio of the first flow stabilizer cover 110 and the second flow stabilizer cover 120 can be controlled between 80% - 95%. This opening ratio can better control the flow velocity and distribution uniformity of the inert gas 300, ensuring the smooth and orderly flow of the gas. Among them, the opening ratio of the first flow stabilizer cover 110 is the percentage of the sum of the cross-sectional areas of all the first through holes 111 on the first flow stabilizer cover 110 in the surface area of the outer peripheral wall of the first flow stabilizer cover 110, and the opening ratio of the second flow stabilizer cover 120 is the percentage of the sum of the cross-sectional areas of all the second through holes 121 on the second flow stabilizer cover 120 in the surface area of the outer peripheral wall of the second flow stabilizer cover 120.

[0088] Furthermore, the cross-sections of the first through hole 111 and the second through hole 211 are circular, square, triangular, or a mixture of multiple shapes.

[0089] As Figures 2a to 2e shown, the cross-sectional shapes of the first through hole 111 and the second through hole 211 can be set according to actual conditions. Different shapes and sizes will affect the opening ratio. Therefore, circular, triangular, square, or other shapes can be selected according to actual conditions, or several shapes can be used in combination to ensure that the opening ratio is controlled between 80% - 95%. Among them, the shape of the cross-section of the hole is not limited.

[0090] In a preferred embodiment of the present invention, the cross-sections of the first through-hole 111 and the second through-hole 211 are circular, and the aperture ranges of the first through-hole 111 and the second through-hole 211 are between 5 and 20 mm.

[0091] That is to say, the size of the aperture in the present invention can be limited within a certain range. By controlling the size of the aperture, the opening rate can be ensured. Preferably, when the cross-sections of the first through-hole 111 and the second through-hole 211 are circular, the aperture range is controlled between 5 and 20 mm to better control the flow direction and flow rate of the gas. Of course, in other embodiments of the present invention, the cross-sectional shape and the size of the aperture of the first through-hole 111 and the second through-hole 120 can also be appropriately adjusted according to the surface area of the first flow stabilizer 110 and the second flow stabilizer 120, which is not limited herein.

[0092] In summary, the flow stabilizer 100 according to the embodiment of the present invention can sort out the flow direction of the inert gas 300 introduced into the secondary furnace chamber 212 of the crystal pulling furnace 200, make the gas flow more orderly, reduce the turbulence intensity of the inert gas 300 in the secondary furnace chamber 212, restrict the flow direction of the inert gas 300, reduce the swing of the single crystal silicon rod caused by the gas flow, help the stable contact between the single crystal silicon rod and the molten liquid surface, reduce the probability of occurrence of phenomena such as single crystal growth dislocation, improve the production efficiency of the single crystal silicon rod, reduce the impurities 400 in the main furnace chamber 211 being carried by the turbulent flow to the secondary furnace chamber 212, and avoid problems such as the impurities 400 contaminating and eroding the crystal rod and the side wall of the hot field component. At the same time, the distance between the first flow stabilizer 110 and the second flow stabilizer 120 can be adjusted to further adjust the flow rate of the gas and ensure the smoothness of the gas flow. The heights of the first flow stabilizer 110 and the second flow stabilizer 120 in the secondary furnace chamber 212 can be adjusted to adapt to growing crystal rods of different lengths, improving the flexibility of the use of the flow stabilizer 100.

[0093] As shown in FIG. 1 and Figure 5 As shown, the crystal pulling furnace 200 according to the embodiment of the present invention includes a furnace body 210. The furnace body 210 includes a main furnace chamber 211 and a secondary furnace chamber 212 connected to the main furnace chamber 211. The secondary furnace chamber 212 is provided with the flow stabilizer 100 as described in the above embodiment.

[0094] That is to say, the flow stabilizing device 100 is arranged in the auxiliary furnace chamber 212 of the crystal pulling furnace 200. During flow stabilization, the inert gas 300 flows in from the upper end of the auxiliary furnace chamber 212, successively passing through the first flow stabilizing cover 110, the second flow stabilizing cover 120, and the guide cylinder 213 of the main furnace chamber 211. After the inert gas 300 passes through the first flow stabilizing cover 110 and the second flow stabilizing cover 120, its flow direction is changed, making the air flow more orderly. After the redirected inert gas 300 enters the main furnace chamber 211, the air flow flows smoothly and orderly, reducing the air flow disorder phenomenon of the inert gas 300. When this air flow flows through the guide cylinder 213 of the main furnace chamber 211 to the surface of the single crystal silicon rod, it can reduce the swing amplitude of the single crystal silicon rod affected by the air flow, contribute to the stable contact between the single crystal silicon rod and the molten liquid surface, reduce the occurrence probability of phenomena such as single crystal growth dislocation, improve the production efficiency of the single crystal silicon rod, and can reduce the impurities 400 in the main furnace chamber 211 being carried by the turbulent flow to the auxiliary furnace chamber 212, which is beneficial to the timely discharge of the impurities 400 from the main furnace chamber and avoids problems such as the impurities 400 contaminating and eroding the crystal rod and the side walls of the thermal field components.

[0095] Preferably, the flow stabilizing device 100 further includes a spacing adjusting mechanism 130 for adjusting the distance between the first flow stabilizing cover 110 and the second flow stabilizing cover 120 to expand the flow stabilizing interval. One end of the first flow stabilizing cover 110 and the second flow stabilizing cover 120 passes through the furnace body of the auxiliary furnace chamber 212, and one end of the first flow stabilizing cover 110 and / or one end of the second flow stabilizing cover 120 is connected to the spacing adjusting mechanism 130.

[0096] That is to say, one end of the first flow stabilizing cover 110 and the second flow stabilizing cover 120 can pass through the furnace wall of the auxiliary furnace chamber 212 and be connected to the spacing adjusting mechanism 130. Or, one end of the first flow stabilizing cover 110 or one end of the second flow stabilizing cover 120 passes through the furnace wall of the auxiliary furnace chamber 212 and is connected to the spacing adjusting mechanism 130, thereby realizing the adjustment of the spacing between the first flow stabilizing cover 110 and the second flow stabilizing cover 120 by the spacing adjusting mechanism 130. Of course, in other embodiments of the present invention, it can also be adopted that one end of the spacing adjusting mechanism 130 passes through the furnace wall of the auxiliary furnace chamber 212 and is connected to the first flow stabilizing cover 110 and / or the second flow stabilizing cover 120, which is not limited herein.

[0097] Preferably, the spacing adjusting mechanism 130 includes a spacing adjusting bracket 131 and a first driving mechanism 132. One end of the spacing adjusting bracket 131 is respectively connected to the first flow stabilizing cover 110 and the second flow stabilizing cover 120, or the spacing adjusting bracket is connected to one end of the first flow stabilizing cover or one end of the second flow stabilizing cover. The first driving mechanism 132 is connected to the spacing adjusting bracket 131 for driving the spacing adjusting bracket 131 to approach or depart from each other to adjust the distance between the first flow stabilizing cover 110 and the second flow stabilizing cover 120.

[0098] That is to say, the spacing adjustment bracket 131 can be arranged outside the secondary furnace chamber. One end of the first flow stabilizing cover 110 and / or the second flow stabilizing cover 120 passes through the furnace wall of the secondary furnace chamber and is connected to the spacing adjustment bracket. The first driving mechanism 132 is connected to the spacing adjustment bracket 131. The first driving mechanism drives the spacing adjustment bracket to move so that the first flow stabilizing cover 110 and the second flow stabilizing cover 120 move up and down in the secondary furnace chamber 212, thereby controlling the spacing between the first flow stabilizing cover 110 and the second flow stabilizing cover 120 to better control the flow direction and flow rate of the inert gas. As in the above embodiment, the height adjustment mechanism can adjust the height of the first flow stabilizing cover 110 and the second flow stabilizing cover 120 in the secondary furnace chamber 212 to adapt to growing single crystal rods of different lengths, improving the flexibility of use of the crystal pulling furnace.

[0099] For the flow stabilizing device 100 in the present invention, adopting the flow stabilizing device 100 of the above embodiment, since the structure and technical effects of the flow stabilizing device 100 have been described in detail in the above embodiment, for other specific structures and effects of the flow stabilizing device, please refer to the flow stabilizing device 100 in the above embodiment and will not be elaborated here.

[0100] The crystal pulling furnace 200 of the present invention can reduce the swing of the single crystal rod caused by the gas flow, contribute to the stable contact between the single crystal rod and the molten liquid surface, reduce the probability of occurrence of phenomena such as single crystal growth dislocation, improve the production efficiency of the single crystal rod, and can reduce the impurities 400 in the main furnace chamber 211 being carried to the secondary furnace chamber 212 by the turbulent flow, avoiding problems such as the impurities 400 contaminating and eroding the crystal rod and the side walls of the thermal field components.

[0101] According to the method for stabilizing and adjusting the inert gas of the present invention, which is applied to the crystal pulling furnace 200, the adjustment method includes introducing the inert gas 300 into the crystal pulling furnace 200 from the secondary furnace chamber 212 of the crystal pulling furnace 200 and adjusting the flow direction of the inert gas 300 introduced into the secondary furnace chamber 212 of the crystal pulling furnace 200.

[0102] As Figure 4 and 5 shown, the flow direction of the inert gas 300 introduced into the secondary furnace chamber 212 of the crystal pulling furnace 200 can be adjusted by arranging the first flow stabilizing cover 110 and the second flow stabilizing cover 120 in the secondary furnace chamber 212 of the crystal pulling furnace 200.

[0103] Preferably, a funnel-shaped first flow stabilizing cover 110 as Figure 1c shown can be used to rectify the inert gas 300 in the secondary furnace chamber 212; a reverse funnel-shaped second flow stabilizing device 120 is used to evenly distribute the rectified inert gas.

[0104] Preferably, as Figure 1e and 1gAs shown, the method for regulating the steady flow of the inert gas further includes rectifying the inert gas 300 after splitting again, and splitting the inert gas 300 after the second rectification again, so as to further improve the steady flow effect of the air flow, or selecting an appropriate steady flow cover according to different production requirements.

[0105] Preferably, the flow direction and flow velocity of the air flow can also be adjusted by adjusting the size of the steady flow interval.

[0106] Preferably, it also includes controlling the height of the inert gas 300 when splitting in the secondary furnace chamber 212 to adapt to the growth of crystal rods of different lengths.

[0107] Since the steady flow method of the steady flow device has been described in detail in the steady flow device of the above embodiment, the steady flow regulation method of the inert gas in the present invention can be stabilized by the steady flow device. Therefore, the steady flow regulation method can refer to the description of the above embodiment and will not be elaborated here.

[0108] According to the method for manufacturing monocrystalline silicon according to an embodiment of the present invention, it is applied to a crystal pulling furnace 200. The crystal pulling furnace 200 includes a main furnace chamber 211 and a secondary furnace chamber 212. The manufacturing method includes:

[0109] Step 1, melting polysilicon in the main furnace chamber 211 of the crystal pulling furnace 200;

[0110] Step 2, bringing the seed crystal into contact with the molten polysilicon phase;

[0111] Step 3, introducing an inert gas 300 into the secondary furnace chamber of the crystal pulling furnace 200 and stabilizing the flow of the inert gas 300. The method for stabilizing the flow of the inert gas 300 includes the method for regulating the steady flow of the inert gas as described in the above embodiment.

[0112] Preferably, the manufacturing method further includes:

[0113] After the polysilicon raw material is completely melted, the seed crystal is brought into contact with the molten polysilicon phase, and when the length of the crystal rod growth does not reach the bottom of the secondary furnace chamber, the size of the steady flow interval is adjusted to adjust the flow direction and flow velocity of the air flow.

[0114] Preferably, the manufacturing method further includes;

[0115] Controlling the height of the inert gas when splitting in the secondary furnace chamber to adapt to the growth of crystal rods of different lengths.

[0116] Preferably, the manufacturing method further includes that when the inert gas flows into the main furnace chamber 211, the inert gas 300 is guided by the guide cylinder 213 so that the inert gas 300 flows to the contact surface of the polysilicon melt and the seed crystal, which can effectively guide the inert gas 300 after steady flow to the contact surface of the melt and the seed crystal, and is more conducive to the rapid growth of the crystal rod.

[0117] The method for manufacturing single-crystalline silicon according to the embodiments of the present invention adopts the method for regulating the steady flow of the inert gas in the above embodiments. Since the method for regulating the steady flow of the inert gas has been described in detail in the above embodiments, for details, please refer to the method in the above embodiments and will not be elaborated herein.

[0118] The method for manufacturing single-crystalline silicon according to the embodiments of the present invention can reduce the swing of the single-crystalline silicon rod caused by the air flow, contribute to the stable contact between the single-crystalline silicon rod and the molten liquid surface, reduce the probability of phenomena such as single-crystal growth dislocations, improve the production efficiency of the single-crystalline silicon rod, and can reduce the impurities 400 in the main furnace chamber 211 being carried to the auxiliary furnace chamber 212 by the turbulent flow, avoiding problems such as the contamination and erosion of the crystal rod and the side walls of the thermal field components by the impurities 400.

[0119] The single-crystalline silicon according to the embodiments of the present invention is obtained by the method for manufacturing single-crystalline silicon as in the above embodiments.

[0120] The single-crystalline silicon of the present invention can avoid the generation of dislocations and has a high purity.

[0121] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the technical field to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship also changes accordingly.

[0122] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the technical field, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for regulating the steady flow of an inert gas, characterized in that, applied to a crystal pulling furnace, the regulating method includes: introducing an inert gas from the auxiliary furnace chamber of the crystal pulling furnace into the crystal pulling furnace, and regulating the flow direction of the inert gas introduced into the auxiliary furnace chamber of the crystal pulling furnace through a first steady flow hood and a second steady flow hood; wherein, the first steady flow hood and the second steady flow hood are installed in the auxiliary furnace chamber of the crystal pulling furnace; both the first steady flow hood and the second steady flow hood are funnel-shaped; one end of the first steady flow hood is a wide opening, and the other end is a narrow opening; one end of the second steady flow hood is a wide opening, and the other end is a narrow opening; the narrow opening ends of the first steady flow hood and the second steady flow hood are arranged adjacent to each other; the first steady flow hood and the second steady flow hood are connected by a spacing regulating mechanism, and the spacing regulating mechanism is used to adjust the distance between the first steady flow hood and the second steady flow hood to expand the steady flow interval; the method includes: the inert gas in the auxiliary furnace chamber flows in from the wide opening end of the first steady flow hood and flows out from the narrow opening end to rectify the inert gas; the rectified inert gas flows into the narrow opening end of the second steady flow hood and flows out from the wide opening end to evenly divide the rectified inert gas flow; a steady flow interval is formed between the gas rectification and the flow division.

2. The method for regulating the steady flow of an inert gas according to claim 1, characterized in that, further comprising: rectifying the divided inert gas again; dividing the inert gas after being rectified again.

3. The method for regulating the steady flow of an inert gas according to claim 1, characterized in that, the method further includes: adjusting the size of the steady flow interval to adjust the flow direction and flow rate of the gas flow.

4. The method for regulating the steady flow of an inert gas according to claim 3, characterized in that, further comprising: controlling the height of the inert gas when it is divided in the auxiliary furnace chamber to adapt to the growth of crystal rods of different lengths.

5. A method for manufacturing monocrystalline silicon, characterized in that, applied to a crystal pulling furnace, the crystal pulling furnace includes a main furnace chamber and an auxiliary furnace chamber, and the manufacturing method includes: melting polysilicon in the main furnace chamber of the crystal pulling furnace; bringing a seed crystal into contact with the molten polysilicon; introducing an inert gas into the auxiliary furnace chamber of the crystal pulling furnace and stabilizing the flow of the inert gas, and the method for stabilizing the flow of the inert gas includes the method for regulating the steady flow of an inert gas according to any one of claims 1-4.

6. The method for manufacturing monocrystalline silicon according to claim 5, characterized in that, applying the method for regulating the steady flow of an inert gas according to claim 3, the manufacturing method further includes: after the polysilicon raw material is completely melted, the seed crystal is brought into contact with the molten polysilicon, and when the length of the crystal rod growth does not reach the bottom of the auxiliary furnace chamber, adjusting the size of the steady flow interval to adjust the flow direction and flow rate of the gas flow.

7. The method for manufacturing monocrystalline silicon according to claim 6, characterized in that, applying the method for regulating the steady flow of an inert gas according to claim 4, the manufacturing method further includes; controlling the height of the inert gas when it is divided in the auxiliary furnace chamber to adapt to the growth of crystal rods of different lengths.

8. The method for manufacturing monocrystalline silicon according to claim 5, characterized in that, The main furnace chamber of the crystal pulling furnace is further provided with a flow guide cylinder, and the manufacturing method further includes: When the inert gas flows into the main furnace chamber, guiding the inert gas through the flow guide cylinder so that the inert gas flows towards the contact surface between the polysilicon melt and the seed crystal.

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