KR20110005053A - Method for controlling oxygen radial gradient of single crystal - Google Patents

Abstract

PURPOSE: A method for controlling the oxygen radial gradient of a single crystal is provided to uniform the concentration of oxygen flowing into the single crystal in a radial direction by optimizing operational parameters. CONSTITUTION: The charge of melt contained in a quartz crucible is increased in order to increase the contact area of the melt and the quartz crucible. A cusp magnetic field is applied to the melt, and Zero-gauss plane is between 0 and -50mm. The rotary speeds of seed and the crucible, a melt gap, the flow rate of inert gas, and pressure in a chamber are controlled based on the increase of the charge of the melt.

Description

Method for controlling oxygen radial gradient of single crystal

The present invention relates to a method for controlling the oxygen concentration gradient of a single crystal, and more particularly, in the radial direction of a single crystal, the oxygen concentration introduced into the single crystal in the process of growing a single crystal having a high oxygen concentration by increasing the melt charge amount in a low oxygen hot zone. It relates to an oxygen concentration gradient control method that can be uniformly controlled.

BACKGROUND OF THE INVENTION Semiconductor wafers used in the manufacture of semiconductor devices today are manufactured by slicing and polishing single crystals grown mainly by the Czochralski (CZ) method. CZ method is a method of growing a single crystal through a solid-liquid interface by dipping the seed in the melt (melt) contained in the quartz crucible and slowly pulling the seed upward while rotating the quartz crucible and the seed in opposite directions.

In the CZ method, a quartz crucible for accommodating the melt is essentially used. Quartz crucibles react with hot melt during single crystal growth. As a result, oxygen atoms are continuously eluted into the melt. The eluted oxygen atoms are transferred to SiOx form and eventually incorporated into the single crystal through the solid-liquid interface. Oxygen atoms incorporated into single crystals improve wafer strength and drag against heat. In addition, the oxygen atom forms a bulk micro defect (BMD) during heat treatment of the wafer, and serves as a gettering site for collecting metallic impurities present in the wafer during the semiconductor process. On the other hand, the oxygen atom may be a factor that adversely affects the yield of semiconductor devices by causing various crystal defects and segregation. Therefore, in the single crystal growth process using the CZ method, it is necessary to appropriately control the oxygen concentration flowing into the crystal through the solid-liquid interface.

Conventionally, a method of changing the design of a hot zone in a single crystal manufacturing apparatus has been mainly used to control the oxygen concentration in the single crystal. For example, the reaction rate of the quartz crucible and the melt can be controlled by adjusting the length of the heater, the power or the relative position of the heater and the quartz crucible, or by changing the structure of the heat shield installed around the outer circumferential surface of the single crystal to adjust the distribution of radiant heat supplied to the melt. The method of control was used.

However, the method of controlling the oxygen concentration of the single crystal by changing the design of the hot zone is not only a hassle to design the hot zone individually according to the various oxygen concentration quality levels of the wafer required by the customer, but also a lot of time according to the hot zone replacement. There is a problem that the test operation cost of the single crystal manufacturing apparatus due to the replacement of the hot zone is increased.

As another example, there is a method of adjusting the contact flow rate per unit time of the melt to the quartz crucible by controlling the rotational speed of the quartz crucible and the rotational speed of the seed. In this method, the concentration of oxygen atoms is controlled by the forced convection of the melt caused by the rotation of the seed. In this way, the single crystal grown in this way has the forced convection near the solid-liquid interface due to the high seed rotation speed, which leads to the center of the single crystal. The oxygen concentration difference between the edge and the edge is reduced, so that the oxygen radial gradient representing the in-plane oxygen concentration of the single crystal has a stable value.

For reference, the oxygen concentration gradient is calculated by Equation 1 using the oxygen concentration value measured at the center of the wafer and the four edges.

(In the above equation, Avg. Edge 4point Oi. Is an average value of oxygen concentration measured at four edges, and Center Oi. Is an oxygen concentration value measured at the center.)

However, when the polysilicon melt loading amount, which is the growth material of the single crystal, is increased for the purpose of increasing the prime length of the single crystal or increasing the oxygen concentration inflow rate, the amount of the melt charge contained in the quartz crucible increases, thereby changing the thermal environment inside the hot zone. Then, the influence of forced convection by the seed rotation or the crucible rotation on the oxygen concentration gradient is reduced. That is, forced convection near the edge of the solid-liquid interface is reduced, and oxygen atoms flowing through the solid-liquid interface are unevenly introduced in the radial direction of the single crystal. As a result, the oxygen concentration gradient level deteriorates based on the radial direction of the single crystal. In addition, the increased melt loading acts as a factor in the rapid rise of natural convection, which leads to a larger difference in oxygen concentration between the center and the edge of the single crystal.

In order to solve this problem, the present inventors repeatedly reset the optimum process parameters in a direction that can increase the oxygen concentration near the edge of the single crystal, and at the same time appropriately control the Ar gas flow rate and the pressure inside the chamber. It was recognized that to reduce the oxygen concentration variation in the radial direction of the single crystal, which led to the creation of the present invention.

The present invention has been devised to solve the above problems of the prior art, by increasing the melt charge amount without changing the structure of the low oxygen hot zone, by optimizing the process parameters in growing the single crystal with increased oxygen concentration inflow, It is an object of the present invention to provide a method for controlling the oxygen concentration gradient of a single crystal capable of uniformly controlling the oxygen concentration introduced into the single crystal in the radial direction.

Oxygen concentration gradient control method of a single crystal according to the present invention for achieving the above technical problem, after dipping the seed in the semiconductor melt contained in the quartz crucible to raise the seed to the top while rotating the seed and the quartz crucible in a solid-liquid interface In the method of growing a single crystal through the method, ZGP (Zero Gauss Plane) having a vertical component of zero magnetic field is solid in a state in which the amount of melt contained in the quartz crucible is increased to increase the contact area between the melt and the quartz crucible. A cusp magnetic field is applied to the melt so as to be positioned between 0 and -50 mm from the interface, and the seed rotation speed and the crucible rotation speed are controlled higher than the seed rotation speed and the crucible rotation speed before the melt charge amount is increased. The flow rate of the inert gas is controlled to be lower than the melt gap and the flow rate of the inert gas before the melt charge amount is increased. And, the pressure in the chamber is characterized by higher than the control pressure in the chamber prior to melt jangipryang is increased, to control the oxygen concentration gradient of the single crystal.

In the present invention, the single crystal growth is performed using a single crystal manufacturing apparatus designed to grow single crystals having an oxygen concentration of 8 to 11 ppma.

Preferably, the oxygen concentration of the single crystal grown under the condition of increasing the melt charge amount is 12 ~ 15ppma.

Preferably, the melt charge amount is increased by 15 to 30% based on the melt weight before the melt charge amount is increased.

Preferably, the cusp magnetic field has a magnetic field strength ratio between 1.4 and 1.8 above and below.

Preferably, the seed rotational speed is controlled to 17 ~ 23rpm.

Preferably, the crucible rotation speed is controlled to 4 ~ 10rpm.

Preferably, the melt gap is controlled to 20 ~ 40mm.

Preferably, the flow rate of the inert gas is controlled to 20 ~ 50slpm.

Preferably, the pressure in the chamber is controlled to 40 ~ 70torr.

According to the present invention, by optimizing the process parameters under conditions in which the melt loading amount is increased, it is possible to uniformly control the oxygen concentration of the single crystal in which the oxygen concentration inflow is increased in the radial direction. Accordingly, even if the structure of the low oxygen hot zone is not changed, the oxygen concentration gradient is excellent and single crystals having a high oxygen concentration can be manufactured, thereby improving productivity and reducing manufacturing costs of the single crystals.

Hereinafter, the Example of the oxygen concentration control method of the silicon single crystal ingot which concerns on this invention is described in detail. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

1 is a schematic configuration diagram of a single crystal manufacturing apparatus used for the implementation of the method for controlling the oxygen concentration gradient of a single crystal according to a preferred embodiment of the present invention.

Referring to FIG. 1, the single crystal manufacturing apparatus includes a chamber 10, which is a space in which single crystals C are grown, and a quartz crucible in which the molten melt M melted at a high temperature is installed in the chamber 10. And a crucible housing 30 surrounding the outer circumferential surface of the quartz crucible 20 and supporting the quartz crucible 20 in a predetermined form, and which is installed at the lower end of the crucible housing 30 to be quartz together with the housing 30. Crucible rotating means 40 for raising or lowering the quartz crucible 20 while rotating the crucible 20 and a heater 50 for heating the quartz crucible 20 spaced apart from a side wall of the crucible housing 30 by a predetermined distance. And the quartz crucible using a heat insulating means 60 installed outside the heater 50 to prevent heat generated from the heater 50 from leaking to the outside and a seed that is seed crystal. From the melt (M) accommodated in 20), single crystal (C) Single crystal pulling means 70 which is pulled while rotating in a direction opposite to the rotational direction of the needle 20 and inert gas (for example, Ar gas) is supplied to the upper surface of the melt M along the outer circumferential surface of the single crystal C. Inert gas supply means 80, magnetic field applying means 90a, 90b (hereinafter referred to collectively as 90) for applying a cusp magnetic field to the quartz crucible 20, and the melt M inside the chamber 10. And an exhaust valve 100 for discharging the oxide, the inert gas, and other impurities evaporated from the outside of the chamber 10 and adjusting the pressure inside the chamber 10. Since these components are typical components of a single crystal manufacturing apparatus using the CZ method, which is well known in the art, detailed description of each component will be omitted.

In the embodiment of the present invention, using a single crystal manufacturing apparatus designed as a low oxygen hot zone for growing a single crystal (C) having an oxygen concentration of 8 ~ 11ppma, the amount of melt charged contained in the quartz crucible 20 in the original low oxygen hot zone The single crystal (C) is grown to increase the oxygen concentration inflow by increasing the target melt charge required to grow the low oxygen single crystal. For example, the single crystal (C) with increased oxygen concentration inflow is a high oxygen single crystal having an oxygen concentration of 12 to 15 ppma.

However, when the high oxygen single crystal is grown under the above conditions, the thermal environment inside the hot zone is changed as the amount of melt charged in the quartz crucible 20 increases, thereby reducing the influence of forced convection due to seed rotation or crucible rotation. In the vicinity of the edge of the solid-liquid interface, the effect of homogenizing the oxygen concentration by forced convection is reduced, causing a problem that the oxygen concentration gradient of the single crystal is deteriorated.

FIG. 2 shows that the amount of melt charge is increased for the purpose of growing a single crystal body having a length of 1900 mm or more and a diameter of 200 mm in a low oxygen hot zone, while the process conditions are set to the conditions before increasing the melt charge, and the single crystal is grown when the single crystal is grown. Graphs and tables showing the oxygen concentration gradient measured for each growth length.

In Fig. 2, the oxygen concentration gradient ORG of the single crystal is calculated using the oxygen concentration values measured at the center of the slug and the four edges of the slug taken from the 500, 700, 900, 1100, 1300, and 1500 mm points. Is the result. ORG was calculated using Equation 1 described above. In the graphs and tables, Oi is the oxygen concentration at the center of the slug, and E1 to E4 represent the oxygen concentrations measured at four edge points.

Referring to FIG. 2, it can be seen that the difference in oxygen concentration between the center and the edge of the single crystal increases as the influence of forced convection at the solid-liquid interface is weakened due to the change in the thermal environment inside the hot zone due to the increase in the melt loading in the low oxygen hot zone. The oxygen concentration in the single crystal center was higher than the oxygen concentration at the edge over the entire length of the single crystal body. In the single crystal body section after 900 mm, the oxygen concentration gradient between the single crystal center and the edge is increased to ORG -10% or less.

Accordingly, the method for controlling the oxygen concentration gradient of the single crystal according to the present invention is characterized by optimizing the process parameters to improve the oxygen concentration gradient level of the single crystal under the condition that the melt charge amount is increased in the low oxygen hot zone.

Next, a method of controlling the oxygen concentration gradient of the single crystal according to the preferred embodiment of the present invention will be described in more detail.

The method for controlling the oxygen concentration gradient of a single crystal according to the present invention is applied when growing a single crystal under a condition in which the melt charge amount filled in the quartz crucible 20 is increased to a melt charge amount set for growing the single crystal in a low oxygen hot zone.

According to an embodiment of the present invention, the melt charge amount is set to a condition that is increased by 15 to 30% based on the melt charge amount of the single crystal manufacturing apparatus designed as a low oxygen hot zone. In this case, even in a low oxygen hot zone, it is possible to grow a high oxygen single crystal with an increased oxygen concentration inflow through increasing the melt charge amount. If the melt charge amount is increased, the surface area of the melt (M) in contact with the quartz crucible 20 is increased to increase the elution amount of oxygen, the effect of increasing the oxygen concentration flowing into the single crystal (C).

According to an embodiment of the present invention, the melt charge amount is increased by about 15 to 30% based on the melt charge amount when a single crystal having a diameter of 200 mm and an oxygen concentration level of 8 to 11 ppm is grown to a length of 150 mm. For reference, the melt loading is calculated based on the volume of the single crystal to be grown as a main parameter.

According to the present invention, during the growth of the single crystal C, the magnetic field applying means 90 applies the cusp magnetic field to the melt M contained in the quartz crucible 20. At this time, the cusp magnetic field is applied so that a zero gauge ZGP (Zero Gauss Plane) having a vertical component of 0 is positioned between 0 and -50 mm based on the solid-liquid interface to maximize the forced convection effect at the solid-liquid interface. . To this end, the upper coil 90a and the lower coil 90b constituting the magnetic field applying means 90 are controlled to increase the lower magnetic field strength than the upper magnetic field strength. Preferably, the magnetic field strength ratio (R = lower magnetic field strength / upper magnetic field strength) is 1.4 to 1.8. Here, since the strength of the magnetic field is proportional to the current applied to the coil, the long-term field strength ratio may be based on the intensity ratio of the current applied to the upper coil 90a and the lower coil 90b.

When the cusp magnetic field is applied to the melt under the above conditions, the magnetic field strength at the solid-liquid interface is weakened, and the forced convection effect at the solid-liquid interface can be exhibited to the maximum. As a result, there is an effect that the oxygen concentration at the solid-liquid interface becomes uniform, and the oxygen concentration gradient of the single crystal is improved.

3 is a diagram illustrating magnetic field intensity distribution (a) when the magnetic field intensity ratio is 1 and magnetic field intensity distribution (b) when the magnetic field strength ratio is 1.8. In FIG. 3, the 0 position of the Y axis represents the top of the heater, the 0 position of the X axis represents the central axis of the quartz crucible, the color represents the magnetic field strength, the strong magnetic field toward red, and the weak magnetic field toward blue. The solid red line indicates the position of the ZGP, and the surface of the melt is approximately -115 mm with respect to the Y axis.

As shown in FIG. 3, when the magnetic field strength ratio is 1 (a), the position of the ZGP is retracted from the solid-liquid interface to be located inside the melt, and the position of the weak magnetic field is also located inside the melt. On the other hand, when the magnetic field strength ratio is 1.8 (b), it can be seen that the position of ZGP is located near the solid-liquid interface and the weak magnetic field is located at this portion. In this case, the influence of the magnetic field on the forced convection at the solid-liquid interface can be minimized. Then, forced convection near the solid-liquid interface can be activated locally to uniform the oxygen concentration distribution in the melt M in the radial direction of the solid-liquid interface.

In addition, the method for controlling the oxygen concentration gradient of the single crystal according to the present invention is to optimize process parameter conditions such as seed rotation speed, crucible rotation speed, melt gap, inert gas flow rate, and chamber pressure during growth of single crystal (C). The oxygen concentration gradient of the single crystal is improved.

Specifically, the seed rotation speed and the crucible rotation speed are controlled to a level higher than the seed rotation speed and the crucible rotation speed that were set for growing single crystals in the low oxygen hot zone. This is because, as the melt charge increases, the forced convection near the solid-liquid interface caused by the rotation of the seed and crucible is relatively weaker than before the melt charge increases.

For example, to increase the melt charge amount to 150kg or more, preferably 180kg or more to grow a single crystal having a body diameter of 200mm to a length of 1900mm or more, the seed rotation speed is controlled to 17 to 23 rpm, and the crucible rotation speed is 4.0 to Control at 10 rpm. These seed and crucible rotational speed values are higher than before the melt charge amount is increased. For example, in a single crystal manufacturing apparatus designed with a low oxygen hot zone, when a single crystal having a body diameter of 200 mm is grown to a length of 1500 mm, the melt loading amount is about 150 kg. In this case, the seed rotation speed is set to about 5 to 17 rpm, and the crucible rotation speed is Set it at about 0.5 to 4.0 rpm.

For reference, even if the melt charge amount is increased, the process proceeds at the seed rotation rate and the crucible rotation speed set in the low oxygen hot zone, which weakens the forced convection near the solid-liquid interface and strengthens the natural convection containing oxygen eluted from the quartz crucible. The oxygen concentration gradient between the edge and the edge is excessively increased and flowering phenomenon occurs in which the outer circumferential surface of the single crystal is unevenly grown, so that the single crystal quality required by the customer cannot be achieved.

According to the present invention, the flow rate of the melt gap and the inert gas is controlled to a level lower than the flow rate of the melt gap and the inert gas which has been set for growing single crystals in the low oxygen hot zone.

For example, in order to increase the melt charge amount to 150 kg or more, preferably 180 kg or more to grow a single crystal having a body diameter of 200 mm to 1900 mm or more, the melt gap is controlled to 20 to 40 mm, and the flow rate of the inert gas is 20 to 50 slmm. To control. These melt gaps and flow rates of the inert gas are values that are lower than those prior to increasing melt charge. For example, when a single crystal having a body diameter of 200 mm is grown to a length of 1500 mm, the melt loading amount is about 150 kg. In this case, the melt gap is set to about 43 mm, and the flow rate of the inert gas is set to 65 to 75 slm.

When the flow rate of the melt gap and the inert gas is controlled under the conditions of the present invention, it is possible to reduce the evaporation amount of SiO at the triple point of the solid-liquid interface and the melt surface. As a result, the oxygen concentration gradient can be improved in the radial direction of the single crystal by increasing the oxygen concentration of the single crystal edge portion.

According to the present invention, in order to further improve the oxygen concentration gradient of the single crystal, the pressure in the chamber is controlled to a level higher than the pressure that was set for growing the single crystal in the low oxygen hot zone.

For example, in order to increase the melt charge amount to 150 kg or more, preferably 180 kg or more in order to grow a single crystal having a body diameter of 200 mm to 1900 mm or more, the pressure in the chamber is controlled to be 40 to 70 torr. These pressure conditions in the chamber are higher than levels prior to increasing the melt charge. For example, when a single crystal having a body diameter of 200 mm is grown to a length of 1500 mm, the melt loading amount is about 150 kg. In this case, the pressure in the chamber is set to 20 to 40 torr.

By controlling the pressure in the chamber under the conditions suggested by the present invention, it is possible to further reduce the amount of evaporation of SiO at the triple point of the solid-liquid interface and the melt surface. As a result, the oxygen concentration gradient can be improved in the radial direction of the single crystal by increasing the oxygen concentration of the single crystal edge portion.

< Experimental Example >

Hereinafter, the present invention will be described in detail through experimental examples. The following experimental examples are described for the purpose of helping the understanding of the present invention, and the present invention should not be construed as being limited to terms or experimental conditions described in the experimental examples.

Comparative example

Silicon single crystal with a body diameter of 200 mm at a condition of increasing the melt loading to 180 kg of a single crystal manufacturing apparatus used to grow a silicon single crystal having an oxygen concentration of 8 to 11 ppm (diameter: 200 mm, body length: 1900 mm or more, melt loading 150 kg). Was grown to a length of at least 1900 mm.

In the single crystal growth process according to the comparative example, no cusp magnetic field was applied to the melt. The melt gap, the seed rotation speed, the crucible rotation speed, the Ar gas flow rate and the pressure in the chamber were set based on the condition that the melt charge amount was 180 kg. That is, the melt gap was set to 43 mm, the seed rotation speed was 10 ~ 19rpm, the crucible rotation speed is 0.5 ~ 4.0rpm, the flow rate of Ar gas is 50 ~ 65slpm, the pressure in the chamber 20 to 40torr.

After completion of the growth of the single crystal, the test slugs were sampled every 10 to 30 cm in the direction of the growth axis, and oxygen concentrations were measured at the centers and four edges of each slug. And the oxygen concentration gradient was calculated for each length section using the measured oxygen concentration value.

Example

Silicon single crystals having the same diameter and length were grown using the same single crystal manufacturing apparatus as the comparative example, but the melt gap, seed rotation speed, crucible rotation speed, Ar gas flow rate and The pressure in the chamber was set. Specific numerical conditions of each process parameter were chosen from the ranges given in the examples of the present invention. That is, the rotation speed of the crucible and the seed was set larger than in the comparative example, the flow rate of the melt gap and the Ar gas was set smaller than in the comparative example, and the pressure in the chamber was set higher than in the comparative example. That is, the melt gap was set to 40 mm or less, the seed rotation speed is 17 ~ 23rpm, the crucible rotation speed is 4 ~ 10rpm, the flow rate of Ar gas is 20 ~ 50slpm, the pressure in the chamber is 40 ~ 70torr. In addition, during the single crystal growth, a cusp magnetic field having a magnetic field intensity ratio of 1.8 was applied to the melt, and the ZGP position of the cusp magnetic field was set within the range shown in the embodiment of the present invention.

After the growth of the single crystals, the test slugs were sampled every 10 to 30 cm in the direction of the growth axis, and oxygen concentrations were measured at the center of each slug and at four edges. And the oxygen concentration gradient was calculated for each length section using the measured oxygen concentration value.

Figure 4 is a graph showing the oxygen concentration gradient for each length section of the single crystal calculated in Comparative Examples and Examples for each growth length of the single crystal.

Referring to FIG. 4, the single crystal prepared by the comparative example was relatively good at an oxygen concentration gradient of about 5% to a section having a body length of 700 mm, but rapidly deteriorated due to an increase in oxygen concentration gradient of more than 10% in a section after 900 mm. It can be seen that. On the other hand, it can be seen that the single crystal prepared by the embodiment can uniformly control the oxygen concentration gradient to less than 5% over the entire body length.

According to the experimental results, using the oxygen concentration gradient control method according to the present invention can not only produce a single crystal having a high oxygen concentration by increasing the melt loading even in a single crystal manufacturing apparatus designed with a low oxygen hot zone, but also prime length of the single crystal. It can be seen that it can contribute to increase the productivity of the single crystal by increasing the and evenly control the oxygen concentration gradient to less than 5% over the entire length of the single crystal.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto, and the technical spirit of the present invention and the following will be understood by those skilled in the art to which the present invention pertains. Various modifications and variations are possible, of course, within the scope of equivalents of the claims to be described.

The following drawings, which are attached to this specification, illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical idea of the present invention, the present invention includes the matters described in such drawings. It should not be construed as limited to.

1 is a schematic configuration diagram of a single crystal manufacturing apparatus used for the implementation of the method for controlling the oxygen concentration gradient of a single crystal according to a preferred embodiment of the present invention.

FIG. 2 shows that the amount of melt charge is increased for the purpose of growing a single crystal body having a length of 1900 mm or more and a diameter of 200 mm in a low oxygen hot zone, while the process conditions are set to the conditions before increasing the melt charge, and the single crystal is grown when the single crystal is grown. Graphs and tables showing the oxygen concentration gradient measured for each growth length.

3 is a diagram illustrating magnetic field intensity distribution (a) when the magnetic field intensity ratio is 1 and magnetic field intensity distribution (b) when the magnetic field strength ratio is 1.8.

Figure 4 is a graph showing the oxygen concentration gradient for each length section of the single crystal calculated in Comparative Examples and Examples for each growth length of the single crystal.

Claims (10)

A method of growing a single crystal through a solid-liquid interface by dipping a seed in a semiconductor melt contained in a quartz crucible, then pulling the seed upward while rotating the seed and the quartz crucible in opposite directions. With the charge amount of the melt accommodated in the quartz crucible increased, the area where the melt and the quartz crucible are in contact is increased. A cusp magnetic field is applied to the melt such that a zero gauge plane (ZGP) with zero vertical component of the magnetic field is located between 0 and -50 mm with respect to the solid-liquid interface. The seed rotation speed and the crucible rotation speed are controlled higher than the seed rotation speed and the crucible rotation speed before the melt charge amount is increased. The flow rate of the melt gap and the inert gas is controlled to be lower than the flow rate of the melt gap and the inert gas before the melt charge amount is increased, The pressure in the chamber is controlled to be higher than the pressure in the chamber before the melt charge is increased, An oxygen concentration gradient control method of a single crystal, characterized in that for controlling the oxygen concentration gradient of the single crystal. The method of claim 1, The single crystal growth control method of the oxygen concentration gradient of the single crystal, characterized in that using a single crystal manufacturing apparatus designed to grow a single crystal having an oxygen concentration of 8 ~ 11ppma. The method of claim 1, Oxygen concentration gradient control method of a single crystal, characterized in that the oxygen concentration of the single crystal grown under the condition of increasing the melt charge amount is 12 ~ 15ppma. The method of claim 1, The melt loading amount of the single crystal oxygen concentration gradient control method characterized in that for increasing the 15 to 30% based on the weight of the melt before the melt charge is increased. The method of claim 1, Oxygen gradient gradient control method of the single crystal characterized in that the magnetic field strength ratio of the upper and lower magnetic field is 1.4 ~ 1.8. The method of claim 1, The seed rotation speed is controlled by the oxygen concentration gradient of the single crystal, characterized in that the control at 17 ~ 23rpm. The method of claim 1, The crucible rotation speed is controlled by the oxygen concentration gradient of the single crystal, characterized in that the control at 4 ~ 10rpm. The method of claim 1, The melt gap is controlled in the oxygen concentration gradient of a single crystal, characterized in that the control to 20 ~ 40mm. The method of claim 1, Oxygen concentration gradient control method of the single crystal, characterized in that the flow rate of the inert gas is controlled to 20 ~ 50slpm. The method of claim 1, Oxygen concentration gradient control method of the single crystal, characterized in that the pressure in the chamber is controlled by 40 ~ 70torr.

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