TW202140869A - Method for producing silicon single crystal - Google Patents

Abstract

The purpose of the present invention is to provide a method for producing a silicon single crystal, whereby it becomes possible to keep an oxygen concentration required for the improvement in slip resistance by a thermal stress in the crystal and to prevent the occurrence of internal rearrangement upon the pulling up of the silicon single crystal. In a step for growing a straight barrel portion of a silicon single crystal, the correlational formula between the oxygen concentration A (*10<SP>18</SP> atoms/cm3) in the single crystal and the single crystal pulling up speed B (mm/min) is the formula: B = -1/4A+0.75, and the oxygen concentration in the single crystal is adjusted to A or more and the single crystal pulling up speed is adjusted to B or more.

Description

Method for manufacturing single crystal silicon

The present invention relates to a method for manufacturing single crystal silicon by pulling single crystal silicon by the Czochralski method (CZ method), and particularly relates to a method that can reduce the internal difference in the pulling of single crystal silicon A method of manufacturing single crystal silicon that suppresses dislocation (dislocation).

The breeding system of single crystal silicon by the CZ method is carried out by filling the quartz crucible 51 installed in the chamber 50 as shown in FIG. The heater 52 around 51 heats and melts the polysilicon to form a silicon melt M. Then, the seed crystal (seed crystal) P installed in the seed chuck is immersed in the silicon melt while making the seed crystal The clamp and the quartz crucible 51 rotate in the same direction or in the opposite direction while pulling the seed crystal clamp.

Generally speaking, before the start of pulling, after the temperature of the silicon melt M is stabilized, the necking of the front end of the seed crystal P is performed by contacting the seed crystal P with the silicon melt M to melt the seed crystal P. The so-called necking is an indispensable process for removing the differential row caused by the single crystal silicon by thermal shock caused by the contact between the seed crystal P and the silicon melt M. The neck P1 is formed by this necking. In addition, the neck P1 generally needs to have a diameter of 3 mm to 4 mm and a length of 30 mm to 40 mm or more.

In addition, as a step after the start of the pulling, the following steps are carried out: the step of forming the shoulder C1 is to expand the crystal to the diameter of the straight body after the necking is completed; the step of forming the straight body C2 is to be The single crystal of the product is grown; and the step of forming the tail (not shown) is to gradually reduce the diameter of the single crystal after the step of forming the straight body.

However, if the crystals are misaligned during the pulling process of the aforementioned single crystal silicon, the wafers cut from the misaligned crystals contain many misalignments, and therefore cannot be used in the manufacture of devices. In response to this problem, Patent Document 1 (Japanese Patent Application Laid-Open No. 2006-347853) discloses a method for growing single crystal silicon, in which the atmosphere gas during single crystal growing contains a gas containing hydrogen atoms. This will suppress the differential displacement due to thermal stress.

Specifically, the partial pressure of hydrogen molecules of the gas containing hydrogen atoms in the aforementioned atmospheric gas is set to 40 Pa to 400 Pa, and the concentration of the hydrogen molecules of the gas containing hydrogen atoms is set to α and When the oxygen gas concentration is set to β, the ratio of the oxygen gas concentration in the aforementioned atmosphere to the volume is α-2β≧3%.

According to the method disclosed in Patent Document 1, since the hydrogen element in the gas containing hydrogen atoms enters the crystal lattice of crystalline silicon, it is equivalent to increasing the concentration of atoms between the crystal lattices of crystalline silicon, which can make the silicon solidify during the process of solidification. The number of inter-lattice atoms taken from the silicon melt into the crystal is reduced. As a result, it is possible to suppress slip dislocation clusters (dislocation clusters) (defects around 10 μm formed as aggregates of excess inter-lattice silicon) caused by thermal stress as the starting point. (slip dislocation).

In addition, Patent Document 2 (Japanese Patent Application Laid-Open No. 2002-187796) discloses a method of heating the single crystal without applying a magnetic field when the single crystal in the growing process is differentially displaced when a magnetic field is applied to pull the single crystal. The output of the heater is increased to be higher than the single crystal manufacturing conditions to melt the aforementioned differentially aligned single crystals, and then a magnetic field is applied again and the heater output is set to the aforementioned single crystal manufacturing conditions to pull the single crystals again.

According to this method, when the single crystal is pulled after meltback (remelting) without applying a magnetic field, the foreign matter on the surface of the melt is prevented from being taken into the single crystal, and it becomes possible to suppress The difference in the shoulder formation process is eliminated, and the yield rate is greatly improved. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2006-347853. [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-187796.

[The problem to be solved by the invention]

However, generally speaking, the amount of inter-lattice atoms introduced increases as the pulling rate of the single crystal decreases, and the amount of strain introduced into the crystal tends to increase. On the other hand, slip resistance tends to increase as the amount of oxygen introduced into the crystal increases. Here, when the amount of strain in the crystal increases and the balance between the strain and the slip resistance collapses, a difference is introduced from the center of the crystal where the stress is large. Since this kind of row is generated inside the crystal (called internal row), the crystal habit line (crystal habit line) on the crystal surface as an indicator of poor row/no row will not disappear. If you want to confirm the row , Inspection after slicing into wafer shape is required. However, the inventions disclosed in Patent Documents 1 and 2 are based on the margin that can be determined by the presence or absence of the aforementioned crystal wobble line, and the aforementioned internal margin is not taken into consideration.

The inventor of this case focused on the relationship between the crystal pulling speed and the crystal oxygen concentration. The crystal pulling speed affects the amount of strain, and the crystal oxygen concentration affects the strain and the slip resistance to maintain a balance. The results of painstaking research , To find out that during the incubation of single crystal silicon by the CZ method, it is possible to control the crystal oxygen concentration and the pulling speed to suppress the internal difference of crystals, and complete the present invention.

The present invention is completed under the aforementioned matters, and its purpose is to provide a method for manufacturing single crystal silicon, which can ensure the oxygen concentration in the crystallization for improving the slip resistance, and can prevent the pulling of the single crystal silicon. When generating internal differences. [Means to solve the problem]

In order to solve the aforementioned problems, the manufacturing method of the single crystal silicon of the present invention is accomplished by pulling the single crystal silicon by the Tchaikrasky method. The correlation formula between the oxygen concentration value A (×10 ¹⁸ atoms/cm ³ ) and the single crystal pulling speed B (mm/min) is set as B=-1/4A+0.75, and the value of the single crystal silicon The oxygen concentration and the aforementioned single crystal pulling speed are controlled so that they meet the values of A and B or more in the aforementioned correlation equation, respectively.

According to the invention of this case, the oxygen concentration and the pulling speed in the crystals during the growth of the straight body part of the crystals are controlled so that they are above their respective threshold values determined based on their correlation equations. Single crystal silicon. Thereby, it is possible to ensure the oxygen concentration for improving the slip resistance in the crystal, and since the pulling speed above the threshold determined by the aforementioned correlation equation is ensured, the amount of introduction of atoms between the lattices is suppressed and the strain is changed. It is difficult to accumulate inside the crystal and can suppress the generation of internal dislocations caused by the strain in the crystal.

In addition, the lower limit of the oxygen concentration in the aforementioned single crystal silicon is more desirably 0.4×10 ¹⁸ atoms/cm ³ , and the upper limit is more desirably 1.8×10 ¹⁸ atoms/cm ³ . In addition, it is more desirable to set the thermal stress in the crystal axis portion of the straight body portion to be less than or equal to 18 MPa von Mises stress. In the case where the aforementioned oxygen concentration and the pulling rate are controlled to be equal to or higher than their respective threshold values determined based on the correlation equation, the thermal stress of the crystal shaft can be made as small as the Mises stress of 18 MPa or less. [Efficacy of invention]

According to the present invention, it is possible to provide a method for manufacturing single crystal silicon, which can ensure the oxygen concentration for improving the slip resistance caused by thermal stress in the crystal, and can prevent the generation of single crystal silicon during pulling. Internally poorly arranged.

Hereinafter, the method of manufacturing the single crystal silicon of the present invention will be explained using drawings. FIG. 1 is a cross-sectional view of a single crystal pulling device implemented with a method of manufacturing a single crystal silicon of the present invention. FIG. 2 is a flowchart showing the flow of a single crystal silicon manufacturing method by the single crystal pulling device of FIG. 1.

The single crystal pulling device 1 is provided with a furnace body 10 formed by overlapping a pull chamber 10b on a cylindrical main chamber 10a, and is provided with a carbon susceptor (or graphite The base) 2 is set to be able to rotate around a vertical axis in the furnace body 10 and can be raised and lowered; and the quartz glass crucible 3 (hereinafter simply referred to as the crucible 3) is held by the aforementioned carbon base 2.

The aforementioned crucible 3 has a straight body portion 3a and a bottom portion 3b formed under the straight body portion 3a, and is configured to be able to rotate around a vertical axis together with the rotation of the carbon base 2. In addition, under the carbon base 2 are provided: a rotation drive unit 14 such as a rotary motor to rotate the carbon base 2 around a vertical axis; and an up-and-down drive unit 15 to move the carbon base 2 up and down. Moreover, the rotation drive control part 14a is connected to the rotation drive part 14, and the raising/lowering drive control part 15a is connected to the raising/lowering drive part 15. As shown in FIG.

In addition, the single crystal pulling device 1 is equipped with a resistance-heated side heater 4, which melts the semiconductor raw material (raw polysilicon) filled in the crucible 3 to form a silicon melt M (the following single It is called melt M); and the pulling mechanism 9 is a wire 6 which pulls the bred silicon single crystal C. A seed crystal P is installed at the front end of the cable 6 of the aforementioned pulling mechanism 9.

In addition, the side heater 4 is connected to a heater drive control unit 4a that controls the amount of supplied electric power, and the lifting mechanism 9 is connected to a rotation drive control unit 9a that controls the rotation drive of the lifting mechanism 9. In addition, in the single crystal pulling device 1, an electromagnetic coil 8 for applying a magnetic field is provided on the outer side of the furnace body 2. When a predetermined current is applied to the electromagnetic coil 8 for applying a magnetic field, a horizontal magnetic field of predetermined strength is applied to the silicon melt M in the crucible 3. The electromagnetic coil 8 for magnetic field application is connected with the electromagnetic coil control part 8a which performs operation control of the electromagnetic coil 8 for magnetic field application.

That is, in this embodiment, a magnetic field applied CZ (Magnetic field applied CZ; magnetic field applied Czochralski) method is implemented to grow a single crystal by applying a magnetic field to the melt M, thereby controlling the convection of the silicon melt M. Seek the stability of single crystalization.

In addition, a radiation shield 7 surrounding the silicon single crystal C is arranged above the melt M formed in the crucible 3. The radiation shield 7 has openings formed on the upper and lower portions to shield the excess radiant heat from the side heater 4, the melt M, etc. from the growing silicon single crystal C, and to rectify the gas flow in the furnace. In addition, the interval between the lower end of the radiation shield 7 and the molten surface is controlled in such a way as to maintain a predetermined distance in accordance with the desired characteristics of the grown single crystal.

In addition, a cylindrical water cooling body 12 is arranged inside the radiation shield 7. The water cooling body 12 is supplied with cooling water by a cooling water supply mechanism 12a, and is configured to maintain a predetermined temperature through circulation.

In addition, the single crystal pulling device 1 includes a computer 11 having a storage device 11a and an arithmetic control device 11b, and a rotation drive control unit 14a, an elevation drive control unit 15a, an electromagnetic coil control unit 8a, a rotation drive control unit 9a, and cooling The water supply mechanism 12a is connected to the arithmetic control device 11b, respectively.

In the single crystal pulling device 1 configured in this way, in the case of growing a silicon single crystal C having a diameter of, for example, 300 mm, pulling is performed as follows. That is, the crucible 3 is initially filled with raw material polysilicon (for example, 350 kg), and based on the program stored in the storage device 11a of the computer 11, the crystal incubation process is started.

First, the furnace body 10 is set in a predetermined atmosphere (mainly inert gas such as argon), and the raw material polycrystalline silicon charged in the crucible 3 is melted by heating by the side heater 4 to form a melt M (Step S1 in Fig. 2). Further, the crucible 3 performs a rotation operation at a predetermined height position and a predetermined rotation speed (rpm) (step S2 in FIG. 2).

Next, start to flow a predetermined current to the electromagnetic coil 8 for magnetic field application, and start to apply a horizontal magnetic field ( Step S3 of Fig. 2). In addition, the cable 6 is lowered and the seed crystal P is in contact with the melt M, and the end of the melted seed crystal P is necked, and the formation of the neck P1 starts (step S4 in FIG. 2). When the neck P1 is formed, the power supply for the side heater 4, the pulling speed, the strength of the magnetic field, etc. are used as parameters to adjust the pulling conditions, and the seed crystal P rotates in a predetermined direction opposite to the direction of rotation of the crucible 3 The speed starts to spin.

Then, the crystal diameter is gradually expanded to form a shoulder portion C1 (step S5 in FIG. 2), and it proceeds to the step of forming a straight body portion C2 as a product part (step S6 in FIG. 2). Here, in the cultivation of the straight body portion C2 by the computer 11, as shown in FIG. 3, the horizontal axis x is set to the value of crystal oxygen concentration A (×10 ¹⁸ atoms/cm ³ ) and the vertical axis y is set to increase When the pulling speed value B (mm/min), the values of A and B determined by the correlation equation of the linear function B=-1/4A+0.75 are used as the threshold to control the pulling speed and the crystal oxygen concentration, so as to increase The pulling speed and the crystalline oxygen concentration are respectively above the threshold value.

Specifically, when the value of the crystal oxygen concentration is set to be the value of the target oxygen concentration of the wafer as a product, and A is set as the target value of the oxygen concentration, the oxygen concentration value A (×10 ¹⁸ Atoms/cm ³ ) is substituted into the aforementioned correlation equation to obtain the value of the pulling speed B=-1/4A+0.75 (mm/min), which is set as the threshold of the pulling speed. That is, the computer 11 performs the pulling control so that the oxygen concentration becomes the target value A or more, and performs the pulling control at the pulling speed of the target value B or more.

When the silicon single crystal C whose crystal oxygen concentration value is A is grown in this way, the pulling rate is controlled to be higher than B, whereby the introduction of atoms between the lattices is suppressed and strain becomes difficult to accumulate in the crystal. The internal displacement caused by the strain in the crystal is suppressed. In addition, the range of the value A of the crystal oxygen concentration is more than expected to be 0.4 (×10 ¹⁸ atoms/cm ³ ) or more and less than 1.8 (×10 ¹⁸ atoms/cm ³ ). This is because the low oxygen concentration limit for crystal oxygen concentration is 0.4 (×10 ¹⁸ atoms/cm ³ ), and if it is 1.8 (×10 ¹⁸ atoms/cm ³ ) or more, there is a difference in crystal pulling. The doubts. Moreover, the range of the value B of the pulling speed is more than 0.3 (mm/min) and less than 1.1 (mm/min) than expected. This is because if the pulling speed is less than 0.3 (mm/min), the ratio of dislocation in the crystal pulling will increase, and if it is 1.1 (mm/min) or more, there is a concern that the crystal will be deformed.

In addition, oxygen in the single crystal was introduced as follows. When the silicon melt M flows against (along) the side wall of the crucible 3, since the silicon in the melting point is chemically active, the silicon melt M reacts with the quartz component of the crucible 3 to melt the side wall of the crucible 3, and O (Oxygen) is taken into the silicon melt M.

To control the oxygen concentration in the single crystal grown from the silicon melt M into which O (oxygen) is introduced, it is better to adjust the furnace pressure (increase the furnace pressure, the crystal oxygen concentration will decrease), thereby controlling the silicon melting The flow (convection) of the liquid M is performed.

Furthermore, by adjusting the temperature of the water cooling body 12, the temperature of the cultivated straight body part C2 is cooled to, for example, 1412°C to 800°C, and the thermal stress of the crystal shaft part is suppressed to the Mises stress, for example, 18 MPa or less. In this way, the thermal stress inside the crystal is suppressed to be low, and the crystal oxygen concentration is controlled above the target value A during the growth of the straight body portion C2, thereby ensuring the amount of crystal oxygen introduced and improving the slip resistance.

As the formation of the straight body C2 of the single crystal silicon C progresses, the carbon susceptor 2 containing the crucible 3 moves up and moves to maintain the melt level M1 relative to the fixed position of the radiation shield 7 and the side heater 4 Location. In addition, a magnetic field with a magnetic flux density set in the range of, for example, 1000 Gauss to 4000 Gauss, and more preferably 2000 Gauss to 3000 Gauss is applied, whereby the natural convection of the melt M is suppressed. In addition, if the magnetic flux density of the horizontal magnetic field is set to be low in the range of 800 Gauss to 1000 Gauss, the melt M becomes unstable and crystal deformation is likely to occur.

Then, when the straight body portion C2 is formed to a predetermined length, it proceeds to the final tail portion step (step S7 in FIG. 2). In this tail process, the contact area between the lower end of the crystal and the melt M will gradually decrease, and the silicon single crystal C and the melt M are cut away, and the single crystal silicon is manufactured.

As described above, according to the present embodiment, the oxygen concentration and the pulling speed in the crystal during the growth of the straight body part of the crystal are controlled so that they are equal to or higher than their respective threshold values determined based on their correlation equations, and the growth is Single crystal silicon. In addition, in the straight body part growing, the thermal stress of the crystal shaft part is suppressed to less than 18 MPa Mises stress. Thereby, the oxygen concentration for improving the slip resistance can be ensured in the crystal, and since the pulling speed above the threshold determined by the aforementioned correlation equation can be ensured, the introduction amount of atoms between the lattices is suppressed. It becomes difficult for strain to accumulate inside the crystal, and it is possible to suppress the generation of internal displacement caused by the strain in the crystal. [Example]

Based on the embodiment, the method of manufacturing the single crystal silicon of the present invention is further explained. (Experiment 1) In Experiment 1, in the single crystal pulling device of the configuration shown in the above embodiment, 360 kg of raw polycrystalline silicon was put into the crucible, and the single crystal silicon with a diameter of 307 mm was pulled. In order to suppress the natural convection of the silicon melt, the magnetic flux density of the horizontal magnetic field applied during the pulling is set to 2500 Gauss.

In addition, the temperature of the water cooling body surrounding the single crystal was adjusted, and the distance from the surface of the single crystal to the surface of the water cooling body was set to 55 mm, and the Mises stress was adjusted to 18 MPa or less. The magnetic field intensity is set to 3000 Gauss. In addition, argon gas was used as the inert gas, and the flow rate of the inert gas was set to 130 l/min. In addition, the furnace internal pressure is set to 15 Torr to 80 Torr. Furthermore, the rotation speed of the crucible was set to 0.5 rpm, and the rotation speed of the single crystal was set to 9.5 rpm (the rotation directions were set to be opposite to each other).

In addition, in Experiment 1, 110 pull tests were carried out. Then, the target crystalline oxygen concentration was set for each test, and the pulling speed was changed variously to perform the pulling. The results of each test in Experiment 1 are shown in the graph of FIG. 4. The graph in Fig. 4 shows the average pulling rate (mm/min) on the vertical axis y and the oxygen concentration (10 ¹⁸ atoms/cm ³ ) in the center of the crystal on the horizontal axis x. The average pulling rate in each test is plotted. The speed is related to the oxygen concentration in the center of the crystal. In addition, in each test, the obtained single crystal was processed into an etched wafer, and oblique light was irradiated to confirm the presence or absence of internal dislocations caused by surface transmission. Then, as shown in Figure 4, in each test, the parts without internal deviations are represented by ◇, and the parts with internal deviations are represented by ×.

According to the graph in Figure 4, in the correlation equation y=-1/4x+0.75 (y is the average pulling speed (mm/min) and x is the oxygen concentration in the center of the crystal (10 ¹⁸ atoms/cm ³ )), the The value A of y when x=B is set as the threshold value of the average pulling speed. When the crystal oxygen concentration becomes B or higher and the pulling speed becomes A or higher, it is determined that there is no internal displacement.

In addition, a photo of the situation where there is no internal runout when checking for internal runout is shown in (a) in FIG. 5, and a photo of the situation where there is an internal runout is shown in (b) in FIG. 5. In the example of the result shown in Fig. 5(b), several cross-shaped reflections with a size of about 5 mm to 20 mm are seen. Since the crystal habit lines have not disappeared, it can be confirmed that these are internal differences.

As shown in the results of this experiment 1 and the graph in Fig. 4, when the single crystal is pulled up to the value of y when the target oxygen concentration is substituted for x with the correlation equation y=-1/4x+0.75, it is confirmed that the inside Poor row will not occur.

(Experiment 2) In experiment 2, among the conditions of experiment 1 above, the conditions that affect the flow (convection) of the silicon melt, the magnetic flux density, the flow rate of the inert gas, the furnace pressure, the crucible, and the rotation speed of the single crystal were changed. The other conditions are the same as those of Experiment 1. Specifically, the magnetic flux density is set to 2000 Gauss, and the flow rate of the inert gas is set to 130 l/min. In addition, the furnace internal pressure is set to 15 Torr to 80 Torr. Further, the rotation speed of the crucible was set to 0.5 rpm, and the rotation speed of the single crystal was set to 9.5 rpm (the rotation directions were set to be opposite to each other).

The results of each test in Experiment 2 are shown in the graph of FIG. 6. The graph in Fig. 6 shows the average pulling speed (mm/min) on the vertical axis y and the oxygen concentration (10 ¹⁸ atoms/cm ³ ) in the center of the crystal on the horizontal axis x. The average pulling rate in each test is plotted. The speed is related to the oxygen concentration in the center of the crystal. In each test, the parts without internal deviations are represented by ◇, and the parts with internal deviations are represented by ×. As shown in the results of Experiment 2 and the graph in Fig. 6, when the single crystal is pulled up to the value of y when the target oxygen concentration is substituted for x with the correlation formula y=-1/4x+0.75, the internal difference is not Will produce.

(Experiment 3) In Experiment 3, among the conditions of Experiments 1 and 2 above, the conditions affecting the flow (convection) of the silicon melt, the magnetic flux density, the flow rate of the inert gas, the furnace pressure, the crucible, and the rotation speed of the single crystal were changed. The other conditions are the same as those of experiments 1 and 2. Specifically, the magnetic flux density is set to 3000 Gauss, and the flow rate of the inert gas is set to 130 l/min. In addition, the furnace internal pressure is set to 15 Torr to 80 Torr. Further, the rotation speed of the crucible was set to 2.0 rpm, and the rotation speed of the single crystal was set to 9.5 rpm (the rotation directions were set to be opposite to each other).

The results of each test in Experiment 3 are shown in the graph of FIG. 7. The graph in Fig. 7 shows the average pulling speed (mm/min) on the vertical axis y and the oxygen concentration in the center of the crystal (10 ¹⁸ atoms/cm ³ ) on the horizontal axis x. The average pulling rate in each test is plotted. The speed is related to the oxygen concentration in the center of the crystal. In each test, the part without internal deviation is indicated by ◇, and the part with internal deviation is indicated by ×. As shown in the results of Experiment 3 and the graph in Fig. 7, when the single crystal is pulled up to the value of y when the target oxygen concentration is substituted for x with the correlation equation y=-1/4x+0.75, the internal difference is not Will produce.

According to the results of the above experiments 1 to 3, in order to suppress the generation of internal dislocations, the correlation between the average pulling speed (mm/min) and the oxygen concentration in the center of the crystal (10 ¹⁸ atoms/cm ³ ) can be defined as y=-1/4x +0.75, in the case where x in the correlation equation y=-1/4x+0.75 is substituted with the target oxygen concentration and the single crystal is pulled above the value of y, it is confirmed that no internal displacement will occur.

(Experiment 4) In Experiment 4, in the experiment of the above experiment 1, under the condition that the pulling speed was set to 0.55 mm/min and the crystal oxygen concentration was set to 1.1E18 atoms/cm ^3, it was confirmed by simulation that Thermal stress generated inside the crystal. In this simulation, the comprehensive thermal analysis software CGSim_Basic produced by STR (Semiconductor Technology Research) is used, and the thermal expansion coefficient is set as 2.6×10 ^-6 K ^-1 , Young's modulus 185 GPa, and Passon’s ratio. (Poisson's ratio) 0.28, density 2330 kg/m ³ . The simulation results are shown in FIG. 8. In Figure 8, it was confirmed that the thermal stress was as small as 18 MPa at the crystal axis near 150 mm above the solid-liquid interface, which improved the slip resistance.

From the results of the above experiments 1 to 4, it was confirmed that according to the present invention, it is possible to prevent the occurrence of internal dislocations caused by strain in the growth of the straight body portion of the single crystal.

1: Single crystal pulling device 2: Carbon base 3: Quartz glass crucible (crucible) 3a: Straight body 3b: bottom 4: side heater 4a: Heater drive control unit 6: Cable 7: Radiation shield 8: Electromagnetic coil for magnetic field application 8a: Solenoid coil control unit 9: Lifting mechanism 9a, 14a: Rotation drive control unit 10: Furnace 10a: Main chamber 10b: Lifting chamber 11: Computer 11a: storage device 11b: Operational control device 12: Water cooling body 12a: Cooling water supply mechanism 14: Rotary drive part 15: Lifting drive 15a: Lifting drive control unit 50: Chamber 51: Quartz Crucible 52: heater C: Monocrystalline silicon C1: Shoulder C2: Straight body M: Silicon melt (melt) M1: Melt level P: seed crystal P1: neck S1~S7: steps

[Fig. 1] is a cross-sectional view of a single crystal pulling device in which the method of manufacturing a single crystal silicon of the present invention is implemented. [FIG. 2] is a flowchart showing the flow of a method of manufacturing single crystal silicon by the single crystal pulling device of FIG. 1. [FIG. 3] is a graph for explaining the manufacturing method of the single crystal silicon of the present invention. Fig. 4 is a graph showing the results of Experiment 1 of the present invention. [Fig. 5] is a photograph showing the results of the Examples and Comparative Examples of the present invention. Fig. 6 is a graph showing the results of Experiment 2 of the present invention. Fig. 7 is a graph showing the results of Experiment 3 of the present invention. [Fig. 8] is a simulated video showing the result of the embodiment of the present invention. [Fig. 9] is a cross-sectional view for explaining the process of pulling single crystal silicon by the Tchaikrasky method.

S1~S7: steps

Claims (3)

A method for manufacturing single crystal silicon is to pull the single crystal silicon by the Tchaikrasky method; in the step of growing the straight body of the single crystal silicon, the value of the oxygen concentration in the single crystal silicon is A×10 ^The correlation between 18 atoms/cm ³ and the single crystal pulling speed B mm/min is set as B=-1/4A+0.75; the oxygen concentration in the aforementioned single crystal silicon and the aforementioned single crystal pulling speed are satisfied respectively The above-mentioned correlation formula A and B above the value of the way to control. The method for manufacturing single crystal silicon described in claim 1, wherein the lower limit value of the oxygen concentration in the single crystal silicon is 0.4×10 ¹⁸ atoms/cm ³ , and the upper limit value is 1.8×10 ¹⁸ atoms/cm ³ . The method for manufacturing single crystal silicon as described in claim 1 or 2, wherein the thermal stress in the crystal axis portion of the straight body portion is set to 18 MPa or less of Mises stress.

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