Feeding method for preparing monocrystalline silicon by using granular silicon and application of feeding method

Abstract

The invention relates to the technical field of semiconductors, in particular to a charging method for preparing monocrystalline silicon by using granular silicon and application of the charging method. The charging method for preparing monocrystalline silicon by using granular silicon comprises the following steps: in the nth batch charging process of repeated crystal pulling and each batch charging process after repeated crystal pulling, a plurality of barrels of granular silicon are continuously added into a heating furnace for dehydrogenation treatment, and when the granular silicon is added, the adding time interval between two adjacent barrels is less than or equal to 46 min; wherein the value of n ranges from 2 to 12. According to the feeding method for preparing the monocrystalline silicon by using the granular silicon, a heating furnace is controlled to be at a low power level when the granular silicon is added, so that online hydrogen volatilization is realized; a compact feeding interval avoids hydrogen jump; the process is adapted, silicon splashing caused by hydrogen explosion is completely eradicated, and the influence of particle silicon application on the crystallization environment is reduced; the influence degree of per unit yield can be reduced by about 50%.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a feeding method for preparing single crystal silicon by using granular silicon and an application thereof. Background Art

[0002] At present, most manufacturers in the world produce polysilicon using the traditional modified Siemens method. Although this method is mature and widely used, it has limitations such as high energy consumption, high cost, and complex process flow. In the photovoltaic industry chain, the energy consumption of silicon material manufacturing accounts for as much as 45%, becoming one of the key factors restricting the reduction of photovoltaic power generation costs.

[0003] As a new process for polysilicon production, granular silicon technology has gradually attracted the attention and attention of the industry. Granular silicon is produced using the silane fluidized bed method (FBR), which has the advantages of small size, low energy consumption, low cost, and high production efficiency. Compared with the modified Siemens method, the production process of granular silicon is shorter and has fewer post-processing steps, which can significantly reduce production costs and energy consumption. In addition, granular silicon has good fluidity and is more suitable for the new generation of continuous feeding and direct pulling process, which helps to improve the overall efficiency of the photovoltaic industry chain.

[0004] Granular silicon is produced through advanced fluidized bed reaction technology, which can meet or even exceed the purity requirements of electronic-grade silicon, providing a high-quality, high-purity raw material basis for CZ-pulled single crystals. Compared with traditional block silicon, granular silicon does not require crushing, which reduces the introduction of impurities and silicon loss caused by crushing, and improves the utilization rate of raw materials. At present, there is no mature and complete technology for the preparation of granular silicon for single crystal silicon.

[0005] In the crystal pulling process, the application of granular silicon brings many advantages, but it also has some disadvantages. The following is an analysis of the main disadvantages of granular silicon in the crystal pulling process:

[0006] 1. Hydrogen jump problem

[0007] 1. High hydrogen content:

[0008] Due to its special production process, granular silicon often contains a high hydrogen content. During the crystal pulling process, hydrogen in silicon is easily released at high temperatures and causes the so-called "hydrogen jump" phenomenon, that is, the crystal suddenly breaks or its quality deteriorates during the growth process. The hydrogen jump problem not only affects the integrity and quality of the crystal, but may also have an adverse effect on the service life of the single crystal furnace thermal field, increasing production costs and maintenance difficulties.

[0009] 2. Limitations of dehydrogenation process:

[0010] Although domestic enterprises have developed a dehydrogenation process to solve the hydrogen jump problem, this process still has certain limitations in practical application. For example, the dehydrogenation effect may not be thorough enough to completely eliminate the risk of hydrogen jump; or the dehydrogenation process may introduce new impurities or defects, causing new effects on crystal quality.

[0011] 2. Purity and impurity issues

[0012] 1. High carbon content:

[0013] During the production process, granular silicon easily collides with the wall of the production equipment, resulting in carbon elements being mixed into the silicon. Although the lining of the equipment used to produce granular silicon by the silane method is mostly made of hard carbon-based materials, long-term use may still lead to an increase in the carbon content in the silicon. High carbon content not only affects the purity of the crystal, but may also have an adverse effect on the electrical properties of the crystal.

[0014] 2. Dust problem:

[0015] Granular silicon has a large surface area and is prone to absorbing dust and other impurities in the air. These dusts may be mixed into the crystals during the crystal pulling process, reducing the purity and quality of the crystals. In order to reduce dust pollution, strict dust prevention measures and purification methods need to be taken, but this also increases production costs and operational difficulties.

[0016] In view of this, the present invention is proposed. Summary of the invention

[0017] The object of the present invention is to provide a feeding method for preparing single crystal silicon using granular silicon and its application. The feeding method for preparing single crystal silicon using granular silicon performs online dehydrogenation of the granular silicon, has a good dehydrogenation effect, avoids hydrogen jump, reduces the impact of the granular silicon application on the crystallization environment, and reduces the impact on unit yield.

[0018] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0019] One aspect of the present invention relates to a method for preparing single crystal silicon using granular silicon, comprising the following steps:

[0020] During the nth batch of feeding and each subsequent batch of feeding of repeated crystal pulling, several barrels of granular silicon are continuously added into the heating furnace and then subjected to dehydrogenation treatment. When adding the granular silicon, the time interval between two adjacent barrels is ≤46 minutes;

[0021] Among them, the value of n is 2 to 12.

[0022] The feeding method for preparing single crystal silicon using granular silicon controls the heating furnace to be at a low power level when the granular silicon is added, thereby realizing online volatilization of hydrogen; compact feeding intervals avoid hydrogen jumps; adapt the process to prevent silicon splashing caused by hydrogen explosion, thereby reducing the impact of granular silicon application on the crystallization environment; the impact on single yield can be reduced by about 50%.

[0023] Preferably, the main power of the heating furnace is 50-90kw.

[0024] Preferably, the bottom-adding power of the heating furnace is 70-80kw.

[0025] Preferably, the flow rate of argon gas introduced into the heating furnace is 120-170 slpm.

[0026] Preferably, the pressure of the heating furnace is 15 to 25 torr.

[0027] Preferably, in each batch of feeding process, the block material is added 10 to 35 minutes after the granular silicon is added.

[0028] Preferably, the total amount of material added in each batch is 3 to 6 barrels, wherein the amount of granular silicon added is 2 to 3 barrels.

[0029] Preferably, the distance between the liquid level in the heating furnace and the feeder cone is regulated to be 550-590 mm.

[0030] Preferably, the turbidity of the granular silicon is less than 120 NTU.

[0031] Another aspect of the present invention also relates to a method for preparing single crystal silicon using granular silicon, including the feeding method for preparing single crystal silicon using granular silicon.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The feeding method for preparing single crystal silicon using granular silicon provided by the present invention controls the heating furnace to be at a low power level when the granular silicon is added, thereby realizing online volatilization of hydrogen; compact feeding intervals avoid hydrogen jumps; and adapting the process, including the flow rate of argon gas, the pressure in the heating furnace, the speed of the crucible, the power of the heating furnace and the position of the crucible, to prevent silicon splashing caused by hydrogen explosion, thereby maximally improving the impact of the application of granular silicon on the crystallization environment; the impact on single yield can be reduced by 50%. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 is the relationship between hydrogen volatilization and temperature;

[0036] Figure 2 It is the relationship between the liquid level position in the heating furnace and the position of the heating furnace cone. DETAILED DESCRIPTION

[0037] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0038] One aspect of the present invention relates to a method for preparing single crystal silicon using granular silicon, comprising the following steps:

[0039] During the nth batch of feeding and each subsequent batch of feeding of repeated crystal pulling, several barrels of granular silicon are continuously added into the heating furnace and then subjected to dehydrogenation treatment. When adding the granular silicon, the time interval between two adjacent barrels is ≤46 minutes;

[0040] The value of n ranges from 2 to 12.

[0041] The feeding method for preparing monocrystalline silicon using granular silicon controls the heating furnace to be at a low power level when the granular silicon is added, thereby realizing online volatilization of hydrogen; the compact feeding interval avoids hydrogen jumps, thereby maximally improving the impact of granular silicon application on the crystallization environment; and the impact on single yield can be reduced by 50%.

[0042] The existing feeding method uses visual judgment to feed materials at the feeding interval. When the CCD screen shows that the soup reaches the set solid-liquid ratio, the material is fed according to the program, which easily leads to the melting of the raw materials. Shortening the feeding interval can avoid the melting of all the raw materials. When adding granular silicon in each batch, the time interval between adjacent barrels is limited to a certain range, which can avoid the granular silicon from seeing the soup during the dehydrogenation process and avoid the melting of silicon materials during dehydrogenation.

[0043] The feeding method of the present invention is implemented during the nth batch of feeding and each subsequent batch of feeding during repeated crystal pulling, which has the least impact on the crystallization environment. For example, if granular silicon is not added for the first feeding, the probability of hydrogen jump is high because the temperature of the heating furnace is too high.

[0044] Furthermore, when adding the granular silicon, the addition time interval between two adjacent barrels is 40 to 46 minutes, including but not limited to any point value of 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes or 46 minutes, or the range value between any two of them.

[0045] Furthermore, the main added power of the heating furnace is 50-90kw, including but not limited to any point value of 50kw, 55kw, 60kw, 65kw, 70kw, 75kw, 80kw, 85kw or 90kw or the range value between any two of them.

[0046] Furthermore, the bottom added power of the heating furnace is 70-80kw, including but not limited to any point value of 70kw, 72kw, 74kw, 76kw, 78kw or 80kw or a range value between any two of them.

[0047] Controlling the main power and bottom power of the heating furnace within a certain range is beneficial to removing hydrogen from granular silicon.

[0048] The temperature in the heating furnace exceeds 1100℃, which is the temperature at which hydrogen will volatilize. High power will cause the melting to be too fast, and hydrogen will jump when the hydrogen is not completely volatilized and melted. By limiting the main power and bottom power, the temperature in the heating furnace can be controlled at around 1100℃. 1100℃ for 30 minutes can meet the dehydrogenation requirements ( Figure 1 ), the granular silicon enters the heating furnace and hydrogen is volatilized.

[0049] Further, the flow rate of argon gas introduced into the heating furnace is 120-170slpm, including but not limited to any point value of 120slpm, 130slpm, 140slpm, 143slpm, 145slpm, 148slpm, 150slpm, 153slpm, 155slpm, 158slpm or 170slpm or any range value between two of them. The argon flow rate defined in the present invention is increased compared with the existing feeding method. After the flow rate is increased, the gas flow rate is accelerated, which is conducive to taking away the dust in the granular silicon and reducing the negative impact on the crystallization environment.

[0050] Furthermore, the pressure of the heating furnace is 15 to 25 torr, including but not limited to any one of 15 torr, 17 torr, 19 torr, 21 torr, 23 torr or 25 torr, or a range between any two of them.

[0051] By adjusting and controlling the flow rate of argon gas introduced into the heating furnace and the pressure inside the furnace, silicon splashing caused by hydrogen explosion can be avoided, thereby reducing the impact of the application of granular silicon on the crystallization environment.

[0052] Furthermore, during each batch of feeding, lump materials are added 10 to 35 minutes (for example, but not limited to, any one of 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes or 35 minutes or a range between any two) after the granular silicon is added. After the granular silicon is added, it is necessary to judge the molten silicon situation of the heating furnace before adding lump materials, and lump materials are added after the molten silicon is seen around the furnace.

[0053] Furthermore, the total amount of each batch of materials added is 3 to 6 barrels, of which the amount of granular silicon added is 2 to 3 barrels. The number of barrels of granular silicon added can be adjusted according to the reported amount of granular silicon. Each batch of granular silicon added is pulled to the side of the furnace for use at one time.

[0054] Furthermore, the mass of the granular silicon contained in each barrel is 80 to 150 kg, including but not limited to any point value of 80 kg, 85 kg, 90 kg, 95 kg, 100 kg, 105 kg, 110 kg, 120 kg, 130 kg, 140 kg or 150 kg, or a range value between any two of them.

[0055] Further, the distance between the liquid level in the heating furnace and the feeder cone is regulated to be 550-590 mm, including but not limited to any point value of 550 mm, 555 mm, 560 mm, 565 mm, 570 mm, 575 mm, 580 mm, 585 mm or 590 mm or any range value between two of them. In the existing feeding method, the distance between the liquid level in the heating furnace and the heating furnace cone is about 280 mm ( Figure 2 ), the present invention increases the distance between the liquid surface and the cone, which is equivalent to increasing the feeding space, and can prevent the granular silicon from splashing onto the heat exchanger and the external guide during the feeding process. Refer to the re-feeding parameter table (Table 1) for distance control, set the re-feeding crucible position according to the re-feeding parameter table, and the furnace automatically adjusts the crucible position according to the parameter setting to achieve the required feeding space.

[0056] Table 1

[0057]

[0058] (Crucible 0 position) First barrel feeding space: bottom edge of guide tube - liquid level:

[0059] (Heat shield travel) + (liquid port distance) + (finishing crucible) = 590 mm.

[0060] Minimum amount of granular silicon:

[0061] (Heat screen travel) + (liquid port distance) + (feed 300kg) = 350mm.

[0062] Through the above calculation process, it is calculated that the maximum and minimum feeding spaces that can be achieved by the distance between the liquid level position in the heating furnace and the feeder cone are 350-590mm.

[0063] Furthermore, the turbidity of the granular silicon is less than 120NTU, including but not limited to any point value of 40NTU, 50NTU, 60NTU, 70NTU, 80NTU, 90NTU, 100NTU, 110NTU or 120NTU or a range value between any two of them. Reducing the turbidity of granular silicon can reduce excessive impurities and dust mixed into the crystal during the crystal pulling process, reduce the production cost of single crystal silicon, and reduce the difficulty of operation.

[0064] Further, the reported material amount is 280-500 kg, including but not limited to any one of 280 kg, 290 kg, 300 kg, 310 kg, 320 kg, 330 kg, 340 kg, 350 kg, 360 kg, 370 kg, 380 kg, 390 kg, 400 kg, 410 kg, 420 kg, 430 kg, 440 kg, 450 kg, 460 kg, 470 kg, 480 kg, 490 kg or 500 kg or any range between two thereof. The reported material amount is the material amount added when adding material in the nth batch of repeated crystal pulling.

[0065] The present invention uses a charging barrel with good sealing performance, and the bottom does not need to be paved with block silicon. Before loading, the charging barrel should be loaded upright and rotated left and right for 2 circles to adjust the seal and prevent leakage.

[0066] In the actual operation of the present invention, when there is granular silicon in the feeding bucket, the granular silicon process must be manually clicked, and when there is block material in the feeding bucket, the granular silicon process is strictly prohibited; the granular silicon bucket is added continuously, and the manual click allows automatic unloading, and it is strictly prohibited to idle the material; when adding block material, the granular silicon is automatically re-added; the granular silicon is hung and added in time, and the feeding interval is strictly enforced. The feeding bucket is cleaned every two weeks on average.

[0067] Another aspect of the present invention also relates to a method for preparing single crystal silicon using granular silicon, including the feeding method for preparing single crystal silicon using granular silicon.

[0068] The embodiments of the present invention will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. If no specific conditions are specified in the examples, the conditions are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be obtained commercially.

[0069] Example 1

[0070] The feeding method for preparing single crystal silicon using granular silicon provided in this embodiment comprises the following steps:

[0071] 1. Select the third batch of feeding and subsequent feeding furnaces, and the reported feeding amount is 280kg;

[0072] 2. The power requirement for adding granular silicon is that the main power of the heating furnace is 70kw, the bottom power of the heating furnace is 70kw, the argon flow rate is 150slpm, and the furnace pressure is 20torr; the distance between the liquid level in the heating furnace and the cone of the heating furnace is regulated to be 570mm;

[0073] 3. The total amount of material added in each batch is 5 barrels. Granular silicon is loaded in the first and second barrels. The turbidity of granular silicon is 115NTU;

[0074] 4. After the crystal rod is taken out from the furnace, the material hanging operation is carried out. After the barrel rotates back to the auxiliary chamber for purification, the first barrel of granular silicon is directly added into the furnace for dehydrogenation treatment. The process conditions need to be confirmed to be qualified. The Jingsheng furnace can set the granular silicon process for process click;

[0075] 5. After the first barrel of granular silicon is added, the second barrel of granular silicon is hung. After the barrel rotates back to the secondary chamber for purification, the second barrel of granular silicon is directly added to the furnace for dehydrogenation treatment. The interval between the addition of the first and second barrels of granular silicon is 45 minutes;

[0076] 6. After all the granular silicon is added continuously, add the lump material 18 minutes later, and add the lump material after soup appears around the furnace;

[0077] 7. Observe the silicon splashing of the guide tube and the water-cooled screen and compare it with the furnace without this process; track the operation of the furnace and the difference in unit output.

[0078] Example 2

[0079] The feeding method for preparing single crystal silicon using granular silicon provided in this embodiment comprises the following steps:

[0080] 1. Select the third batch of feeding and subsequent feeding furnaces, and the reported feeding amount is 280kg;

[0081] 2. The power requirements for adding granular silicon are that the main power of the heating furnace is 60kw, the bottom power of the heating furnace is 75kw, the argon flow rate is 140slpm, and the furnace pressure is 25torr; the distance between the liquid level in the heating furnace and the cone of the heating furnace is regulated to be 550mm;

[0082] 3. The total amount of material added in each batch is 3 barrels. Granular silicon is placed in the first and second barrels. The turbidity of granular silicon is 100NTU.

[0083] 4. After the crystal rod is taken out from the furnace, the material hanging operation is carried out. After the barrel rotates back to the auxiliary chamber for purification, the first barrel of granular silicon is directly added into the furnace for dehydrogenation treatment. The process conditions need to be confirmed to be qualified. The Jingsheng furnace can set the granular silicon process for process click;

[0084] 5. After the first barrel of granular silicon is added, the second barrel of granular silicon is hung. After the barrel rotates back to the secondary chamber for purification, the second barrel of granular silicon is directly added to the furnace for dehydrogenation treatment. The interval between the addition of the first and second barrels of granular silicon is 40 minutes;

[0085] 6. After all the granular silicon is added continuously, add the lump material 18 minutes later, and add the lump material after soup appears around the furnace;

[0086] 7. Observe the silicon splashing of the guide tube and the water-cooled screen and compare it with the furnace without this process; track the operation of the furnace and the difference in unit output.

[0087] Example 3

[0088] The feeding method for preparing single crystal silicon using granular silicon provided in this embodiment comprises the following steps:

[0089] 1. Select the third batch of feeding and subsequent feeding furnaces, and the reported feeding amount is 280kg;

[0090] 2. The power requirement for adding granular silicon is that the main power of the heating furnace is 75kw, the bottom power of the heating furnace is 80kw, the argon flow rate is 160slpm, and the furnace pressure is 15torr; the distance between the liquid level in the heating furnace and the cone of the heating furnace is regulated to be 590mm;

[0091] 3. The total amount of material added in each batch is 6 barrels. The granular silicon is placed in the first barrel, the second barrel and the third barrel. The turbidity of the granular silicon is 80NTU.

[0092] 4. After the crystal rod is taken out from the furnace, the material hanging operation is carried out. After the barrel rotates back to the auxiliary chamber for purification, the first barrel of granular silicon is directly added into the furnace for dehydrogenation treatment. The process conditions need to be confirmed to be qualified. The Jingsheng furnace can set the granular silicon process for process click;

[0093] 5. After the first barrel of granular silicon is added, the second barrel of granular silicon is hung. After the barrel rotates back to the secondary chamber for purification, the second barrel of granular silicon is directly added to the furnace for dehydrogenation treatment. The interval between the addition of the first and second barrels of granular silicon is 46 minutes;

[0094] 6. After all the granular silicon is added continuously, add the lump material 18 minutes later, and add the lump material after soup appears around the furnace;

[0095] 7. Observe the silicon splashing of the guide tube and the water-cooled screen and compare it with the furnace without this process; track the operation of the furnace and the difference in unit output.

[0096] Comparative Example 1

[0097] The difference between this comparative example and Example 1 is that the main added power is 95kw.

[0098] Comparative Example 2

[0099] The difference between this comparative example and Example 1 is that the bottom added power is 95kw.

[0100] Comparative Example 3

[0101] The only difference between this comparative example and Example 1 is that the flow rate of argon gas introduced into the heating furnace is 80 slpm.

[0102] Comparative Example 4

[0103] The difference between this comparative example and Example 1 is that the distance between the liquid level position in the heating furnace and the cone of the heating furnace is regulated to be 330 mm.

[0104] Experimental example

[0105] The unit yield of each embodiment and comparative example was counted, and the whole furnace was added according to this scheme, and the final unit yield was calculated: the sum of the available lengths of the crystal rods / conversion coefficient / number of operating days, and the results are shown in Table 2.

[0106] Table 2

[0107]

[0108]

[0109] It can be seen from Table 1 that after operating according to this invention, the difference in yield after adding granular silicon and without adding granular silicon can be reduced from {(162.1+164.6+165.2+161.5) / 4-171=7.7}7.7kg / furnace / day to {(168.2+167.3+166.7) / 3-171=3.6}3.6kg / furnace / day, and the yield impact is reduced by 53.2%.

[0110] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A feeding method for preparing single crystal silicon using granular silicon, characterized in that: The following steps are involved: During the nth batch of feeding and each subsequent batch of feeding of repeated crystal pulling, several barrels of granular silicon are continuously added into the heating furnace and then subjected to dehydrogenation treatment. When adding the granular silicon, the time interval between two adjacent barrels is ≤46 minutes; Among them, the value of n is 2 to 12.

2. The method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The main power of the heating furnace is 50-90kw.

3. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The bottom heating power of the heating furnace is 70-80kw.

4. The method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The flow rate of argon gas introduced into the heating furnace is 120-170 slpm.

5. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The pressure of the heating furnace is 15 to 25 torr.

6. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: During each batch of feeding, the lump material is added 10 to 35 minutes after the granular silicon is added.

7. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The total amount of material added in each batch is 3 to 6 barrels, among which the amount of granular silicon added is 2 to 3 barrels.

8. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The distance between the liquid level in the heating furnace and the feeder cone is regulated to be 350-590 mm.

9. The feeding method for preparing single crystal silicon using granular silicon according to claim 1, characterized in that: The turbidity of the granular silicon is less than 120 NTU.

10. A method for preparing single crystal silicon using granular silicon, characterized in that: The invention comprises the feeding method for preparing single crystal silicon by using granular silicon as described in any one of claims 1 to 9.

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