KR100221087B1 - Silicon single crystal and its growing method - Google Patents

Abstract

In the silicon single crystal growth method by the magnetic field applying Czochralski method, the cusp is installed during the crystal growth using a magnetic field applied Czochralski method in which the solenoid coils with opposite directions of current are installed up and down outside the single crystal growth path. By applying the magnetic field while controlling the type of magnetic field and the intensity of the magnetic field, two blocks of medium oxygen concentration and low oxygen concentration are formed in one silicon single crystal rod to meet various oxygen concentration specifications and at the same time, Silicon single crystal rods with a uniform distribution can be produced.

Description

Silicon single crystal growth method and silicon single crystal

[Industrial use]

The present invention relates to a silicon single crystal growth method by magnetic field applying Czochralski (MCZ) method, and more particularly, by growing the silicon single crystal while controlling the time and the intensity of the magnetic field of the cusp type It is possible to form two blocks having low oxygen concentration and medium oxygen concentration in the crystal of, and the growth of silicon single crystal by the magnetic field or Czochralski method which can save the power cost by applying the magnetic field by improving the magnetic field application efficiency. It is about a method.

[Prior art]

Silicon wafers that are mainly used as substrates in the manufacture of semiconductor devices generally produce high-purity polycrystalline silicon rods, followed by Czochralski (CZ) crystal growth method or floating-zone (FZ) crystal growth method. Single crystals are grown from polycrystalline silicon to produce single crystal silicon rods, and thinly cut to produce silicon wafers. The wafers are mirror-polished on one surface of the wafer, cleaned, and finally manufactured. N-type and p-type silicon wafers are prepared by adding appropriate dopants during single crystal growth.

In the single crystal silicon crystal growth method, Czochralski crystal growth and floating zone crystal growth are used.

까지 가열하는 방법이다. 사용하는 도가니는 석영(SiO₂)으로 제작되며 가열방법은 고주파가열이나 열저항법을 이용한다. 결정성장시에는 도가니를 회전시켜 온도가 부위에 관계없이 일정하게 유지되도록 한다. 결정성장기(crystal puller) 주위는 용융실리콘의 오염방지를 위해 아르곤(Ar) 가스를 채우기도 한다. 실리콘의 온도가 안정되면 실리콘 시편이 부착된 암(arm)을 천천히 하강하여 용융 실리콘의 표면에 닿게 한다. 이 실리콘 시편은 종자결정(seed crystal)이라 하며 차후에 보다 큰 결정을 성장시키기 위한 출발원료이다. 종자결정의 아랫부분이 용융실리콘 속에서 녹기 시작하면 실리콘을 지지하는 암(arm) 혹은 케이블의 하강운동이 상향운동으로 바뀐다. 이 때 종자결정을 용융실리콘으로부터 천천히 끄집어 내면 종자결정에 맞닿은 용융실리콘이 응고되면서 종자결정과 동일한 결정구조를 가지게 된다. 한편 암 또는 케이블은 상향 운동을 계속하여 보다 큰 결정을 성장시키는데 결정성장은 도가니 속의 실리콘이 일정량 남이 있을 때까지 계속된다. 이런 과정에서 도가니와 종자결정의 인상속도와 도가니의 온도를 적절히 조절하면, 균일한 직경의 단결정을 얻을 수 있다. 불순물의 농도는 결정성장에 앞서 실리콘의 도핑 농도를 높여줌으로써 조절할 수 있다.Czochralski crystal growth method uses polycrystalline silicon specimens in the crucible as 1415, the melting point of polycrystalline silicon.

How to heat up. The crucible used is made of quartz (SiO ₂ ) and the heating method uses high frequency heating or heat resistance method. During crystal growth, the crucible is rotated to keep the temperature constant regardless of the site. Around the crystal puller may be filled with argon (Ar) gas to prevent contamination of the molten silicon. Once the temperature of the silicon is stable, the arm with the silicon specimen is slowly lowered to reach the surface of the molten silicon. This silicon specimen is called a seed crystal and is the starting material for later growth of larger crystals. When the lower part of the seed crystal starts to melt in the molten silicon, the downward movement of the arm or cable supporting the silicon is changed to upward movement. At this time, when the seed crystal is slowly pulled out from the molten silicon, the molten silicon in contact with the seed crystal solidifies and has the same crystal structure as the seed crystal. Arms or cables, on the other hand, continue to move upward to grow larger crystals, which continue until a certain amount of silicon remains in the crucible. In this process, if the pulling speed of the crucible and the seed crystal and the temperature of the crucible are properly adjusted, single crystals of uniform diameter can be obtained. The concentration of impurities can be controlled by increasing the doping concentration of silicon prior to crystal growth.

In addition, the floating zone crystal growth method uses a polycrystalline silicon rod prepared in advance. A silicon rod having a predetermined diameter is placed in the crystal growth group so that the upper end of the silicon rod is in contact with the seed crystals fixed at the upper side of the crystal growth phase and the lower end thereof. The induction heating coil is wound around the reaction tube into which the silicon rod is inserted and the atmosphere in the reaction tube is controlled. When the silicon rod starts to melt from the seed crystal part in the longitudinal direction of the rod due to the heat generated by the coil, the coil moves upward while the molten portion moves upward in the longitudinal direction of the silicon rod. On the other hand, the first molten portion starts to solidify from where it is in contact with the seed crystal and has the same crystal structure as the seed crystal. In addition, as the molten portion moves in the longitudinal direction of the silicon rod, the polycrystalline silicon rod is also melted to become a single crystal silicon rod after solidification. In the floating zone growth method, the diameter of the silicon rod is controlled by controlling the moving speed of the heating coil, and the impurity concentration can be adjusted by appropriately doping the gas containing the dopant in the melting zone of the polycrystalline silicon rod.

On the other hand, it has been found that the application of a magnetic field around the crucible interferes with the tropical currents occurring in the silicon melt, and on the basis of this, the magnetic field or Czochralski method is currently used. This method demonstrates that Lorentz's law applies to molten silicon that the current is induced when the conductor crosses the magnetic field line and that the induced current is in the opposite direction to the change that causes it, resulting in the suppression of tropical currents. It is used. This disruption of the tropical stream causes small temperature fluctuations at the crystal and melt interfaces, resulting in very small fluctuations in the diameter and resistance of the ingots, and reduced oxygen transport from the crucible wall to the solid phase interface, thus introducing less oxygen into the ingots. do. In the magnetic field-applied Czochralski method, 7 to 12 ppma of oxygen is injected, while in the conventional Czochralski method, oxygen of 13 to 19 ppma is introduced. Due to the lower oxygen content, very little oxygen thermal donor is formed and it is reported that problems caused by the association of oxygen such as precipitation and stacking are reduced.

3000Gauss의 수평자장 또는 커스프 자장(cusp field)을 인가하는 것에 의해 도가니 내의 실리콘 용융액의 대류를 억제함으로써 산소 농도를 제어함과 동시에 품질의 균일화를 꾀하였다.In the silicon single crystal growth method by the magnetic field applying Czochralski method, in order to control the oxygen concentration in the crystal rod, 1000

By applying a horizontal or cusp field of 3000 Gauss to suppress convection of the silicon melt in the crucible, the oxygen concentration is controlled and the quality is uniform.

Cusp magnetic field is a type of magnetic field coordination for sealing high temperature plasma. It is a magnetic field coordination obtained by arranging linear conductors in parallel at four points and allowing currents to flow in opposite directions between neighbors. This is called. Sealing has the drawback that there are many particle escapes (cusp losses) from the cusp because of the zero magnetic field.

When the silicon single crystal is grown by applying the cusp magnetic field, since the magnetic field of the same intensity is applied from the beginning, the difference in oxygen concentration is large in the crystal growth direction, and the burden of power cost is applied because the magnetic field of the same intensity is applied until the end. Considering the oxygen concentration in the second half, the range that can control the oxygen concentration is extremely limited.

The horizontal magnetic field of the applied magnetic field has a problem that the temperature distribution becomes asymmetrical in the axial direction and thus the in-plane homogeneity of the wafer is inferior.

The present invention has been made to solve the problems of the prior art, an object of the present invention is to form two blocks of low and medium oxygen concentration in one crystal, the oxygen concentration distribution on the wafer surface is uniform An object of the present invention is to provide a silicon single crystal growth method using a cusp magnetic field or Czochralski method, in which silicon single crystal is grown and power consumption is low.

1 is a cross-sectional view schematically showing a magnetic field applying single crystal growth apparatus according to an embodiment of the present invention.

2 is a graph showing magnetic field application conditions applied to an embodiment of the present invention.

FIG. 3 shows the in-plane distribution of oxygen concentration at each site of the silicon single crystal grown by the cusp-type magnetic field or single crystal growth method of the present invention, measured by Fourier transform infrared (FT-IR). Graph showing the length of a single crystal.

4 is a graph showing the in-plane distribution of the oxygen concentration at each site of the silicon single crystal grown by the conventional Czochralski growth method by the length of the single crystal by measuring by FT-IR.

5 is a graph showing the in-plane distribution of oxygen concentration at each site of the silicon single crystal grown by the conventional magnetic field applying Czochralski growth method by FT-IR and showing the length of the single crystal by the length of the single crystal.

* Explanation of symbols for main parts of the drawings

1a: Upper coil of cusp magnetic field applying device 1b: Hacoil of cusp magnetic field applying device

2: graphite heating element 3: graphite crucible

4: quartz crucible 5: silicon solution

6: crystal 7: seed crystal

8: rotating shaft 9: cable

10: crystal growth furnace 11: neck

12: thermos 13: shoulder

[Means for solving the problem]

The present invention has the following configuration to achieve the above object of the present invention.

In the present invention, the polycrystalline silicon is dissolved by heating to form a silicon solution, the seed crystals are brought into contact with the surface of the silicon solution, and the seed crystals are taken out when the lower part of the seed crystals start to melt in the silicon solution to form a silicon single crystal. In the silicon single crystal growth method comprising growing, and applying a cusp magnetic field during the silicon single crystal growth, the cusp magnetic field application does not apply a magnetic field until a block of medium oxygen concentration is formed in the single crystal. After the block of medium oxygen concentration is formed in the single crystal, the intensity of the magnetic field is gradually increased to a rate at which a uniform low oxygen concentration block can be formed, and after reaching the magnetic field strength to obtain a low oxygen concentration crystal, The unity is gradually reduced in intensity at a rate at which uniform low oxygen concentration blocks can be formed. This growth is to zero the intensity of the magnetic field about to be completed, and provides a silicon single crystal growth method that continuously formed a low oxygen concentration and a uniform block the oxygen concentration in the block of the grown single crystal.

일 때, 상코일의 전류를 21.5A/

의 비율로 증가시키고, 단결정의 길이가 30

인 지점에서 상코일의 전류를 6.1A/

의 비율로 감소시키는 것이 바람직하다.The ratio of the magnetic field strength described above is that the length of the single crystal is 20

When the current of the phase coil is 21.5A /

Increasing the ratio of single crystal to 30

At the point of

It is desirable to reduce the ratio of.

25

일 때는 산소 농도가 7

8

10¹⁷개/

³이고, 단결정의 길이가 25

60

까지는 산소 농도가 5

6

10¹⁷개/

³인 실리콘 단결정을 제공한다.In the present invention, in the silicon single crystal produced by the silicon single crystal growth method described above, the length of the single crystal is 0.

25

When the oxygen concentration is 7

8

10 to ¹⁷ pcs /

³ and the length of the single crystal is 25

60

Oxygen concentration up to 5

6

10 to ¹⁷ pcs /

^It provides a silicon single crystal of ^three .

[Action]

10

10¹⁷개/

³

6

10¹⁷개/

³

이상 줄일 수 있다.In the present invention, the silicon single crystal growth method is a cusp magnetic field or a silicon single crystal growth method by Czochralski growth method. After formation of a medium oxygen concentration block in a single crystal, a magnetic field is obtained to obtain a uniform low oxygen concentration crystal. This method is applied in a manner of increasing the strength of, and then gradually decreasing the strength of the magnetic field to zero at the end of crystal growth. 7 in one decision by these methods

10

10 to ¹⁷ pcs /

³

6

10 to ¹⁷ pcs /

³

Can be reduced.

In the present invention, the magnetic field is gradually increased to form a block having a medium oxygen concentration by growing in a general Czochralski method without first applying a magnetic field, and then forming a uniform low oxygen concentration block. After reaching the target magnetic field strength, the strength of the magnetic field is reduced, and finally the strength of the magnetic field is zero.

10

10¹⁷개/

³인 중 산소 농도와 3

6

10¹⁷개/

³인 저 산소 농도의 특성을 갖는 2개의 블록이 형성된다. 커스프 자장을 성장도중, 임의의 지점에서부터 처음으로 인가함으로써 마그네트의 효율이 향상되며 균일한 저 산소 농도의 결정성장이 용이하다. 본 발명에 의하면, 용융부터 결정성장을 개시하여 임의의 지점까지는 자장을 인가하지 않으며, 임의의 지점에 도달하였을 때 자장의 세기를 일정비율로 서서히 증가시킨다. 자장의 세기가 목표치에 도달했을 때 다시 자장의 세기를 일정비율로 줄여 가는 방법에 의해 결정 중에서의 산소 농도를 폭 넓은 범위에서 제어함이 가능하다.Among the silicon crystal rods grown by this method, [0i] is 7

10

10 to ¹⁷ pcs /

³ 3 and the oxygen concentration in the

6

10 to ¹⁷ pcs /

³ is a two-block having the properties of low oxygen concentration is formed. By applying the cusp magnetic field for the first time from any point during the growth, the efficiency of the magnet is improved and the crystal growth of uniform low oxygen concentration is easy. According to the present invention, the magnetic field is not applied to any point by starting crystal growth from melting, and when the point is reached, the intensity of the magnetic field is gradually increased at a constant rate. When the strength of the magnetic field reaches the target value, it is possible to control the oxygen concentration in the crystal in a wide range by reducing the strength of the magnetic field to a certain ratio again.

The following presents a preferred embodiment to aid the understanding of the present invention. However, the following examples are merely provided to more easily understand the present invention, and the present invention is not limited to the following examples.

EXAMPLE

Representative Example

The following describes an embodiment of the present invention with reference to the drawings. 1 is a cross-sectional view schematically showing the crystal growth apparatus used in the embodiment of the present invention. The crystal growth apparatus of FIG. 1 includes the upper coil 1a and the lower coil 1b, the graphite heating element 2, the graphite crucible 3, the quartz crucible 4, the silicon solution 5, and the crystal of the cusp magnetic field applying device. (6), seed crystal (7), rotary shaft (8), cable (9), and crystal growth furnace chamber (chamber) (10). Using such a crystal growth apparatus, silicon single crystals are grown by the following single crystal growth method.

5

로 유지하면서 끌어 올린다. 일정한 직경의 네크(11)가 형성되면 케이블(9)의 인상속도를 줄여 직경이 207

가 되도록 쇼율더(shoulder; 13)를 형성한다. 쇼울더가 형성되면 흑연발열체(2) 및 케이블(9)의 인상속도를 조절하여 직경 207

의 실리콘 단결정을 성장한다. 이 때 케이블(9)과 도가니 회전축(8)은 서로 반대방향으로 회전한다.Polycrystalline silicon is charged into a quartz crucible 4 in a crystal growth furnace chamber to form a silicon solution 5 by heating melting. After the heat dissolution is completed, the seed crystal 7 is immersed in the silicon solution 5 by lowering the cable 9 when the constant temperature is maintained. The cable (9) has a diameter of 4

5

Pull it up while keeping it as it is. When the neck 11 having a constant diameter is formed, the pulling speed of the cable 9 is reduced to decrease the diameter to 207.

A shoulder 13 is formed to be. Once the shoulder is formed, the pulling speed of the graphite heating element (2) and the cable (9) is adjusted to increase the diameter 207.

Grow silicon single crystal. At this time, the cable 9 and the crucible rotation shaft 8 rotate in opposite directions to each other.

성장한 지점에서 자장인가 장치를 사용하여 자장의 세기를 일정비율로 서서히 증가시킨다. 자장인가 장치는 상코일(1a)과 하코일(1b)인 두 개의 솔레노이드 코일로 구성되어 있으며 전류의 방향은 반대이다. 따라서 결정성장로 내에서 자장의 분포는 커스프 형태를 띠게 된다.As shown in Figure 2, the decision is 20

At the point of growth, the magnetic field applying device is used to gradually increase the intensity of the magnetic field at a constant rate. The magnetic field applying device is composed of two solenoid coils, the upper coil 1a and the lower coil 1b, and the direction of the current is reversed. Therefore, the distribution of the magnetic field in the crystal growth furnace has a cusp shape.

성장된 지점에서 도가니 벽에 걸리는 자장의 세기가 380Gauss로 되도록 조절한다. 일정한 직경을 유지하며 성장이 되는 결정 성장의 완료시점 직전에 자장의 세기가 0이 되도록 일정한 비율로 자장의 세기를 줄인다. 일정 시간동안 냉각시킨 후에 결정을 성장로 밖으로 꺼내면 207

, 일정 직경부의 길이가 64

인 실리콘 단결정이 얻어진다.The length of the crystal is 30

Adjust the strength of the magnetic field on the crucible wall to 380 Gauss at the point of growth. The strength of the magnetic field is reduced at a constant rate so that the strength of the magnetic field becomes zero immediately before the completion of crystal growth while maintaining a constant diameter. After cooling for a period of time, the crystals are taken out of the growth furnace.

, The length of certain diameter part is 64

Phosphorus silicon single crystal is obtained.

Example 1

5

로 유지시키면서 끌어 올렸다. 일정한 직경의 네크(11)가 형성되면 케이블(9)의 인상속도를 줄여 직경이 207

가 되도록 쇼울더(13)를 형성하였다. 쇼율더가 형성되면 흑연발열체(2)의 온도 및 케이블(9)의 인상속도를 조절하여 직경 207

의 실리콘 단결정을 성장시켰다. 이 때 케이블(9)과 도가니 회전축(8)은 서로 반대방향으로 회전을 하였다.Polycrystalline silicon was charged into a quartz crucible 4 in a crystal growth furnace chamber to form a silicon solution 5 by heat dissolution. After the heat dissolution was completed, the seed crystal 7 was immersed in the silicon solution 5 by lowering the cable 9 when the constant temperature was maintained. The cable (9), the diameter of the neck (11) is 4

5

Pulled up while maintaining. When the neck 11 having a constant diameter is formed, the pulling speed of the cable 9 is reduced to decrease the diameter to 207.

The shoulder 13 was formed so as to be. Once the show rate is formed, the temperature of the graphite heating element 2 and the pulling speed of the cable 9 are adjusted to adjust the diameter 207.

Silicon single crystals were grown. At this time, the cable 9 and the crucible rotating shaft 8 rotated in opposite directions to each other.

성장한 지점에서 자장인가 장치를 사용하여 자장의 세기를 일정비율로 서서히 증가시켰다. 결정의 길이가 30

성장된 지점에서 도가니 벽에 걸리는 자장의 세기가 380Gauss로 되도록 조절하였다. 일정한 직경을 유지하며 성장되는 결정 성장의 완료 시점 직전에 자장의 세기가 0이 되도록 일정한 비율로 자장의 세기를 줄였다. 일정 시간동안 냉각시킨 후에 결정을 성장로 밖으로 꺼내면 직경 207

, 일정 직경부의 길이가 64

인 실리콘 단결정이 얻어진다.As shown in Figure 2, the decision is 20

At the point of growth, the intensity of the magnetic field was gradually increased at a constant rate using a magnetic field application device. The length of the crystal is 30

At the point of growth, the intensity of the magnetic field applied to the crucible wall was adjusted to 380 Gauss. The strength of the magnetic field was reduced at a constant rate such that the strength of the magnetic field became zero immediately before the completion of crystal growth while maintaining a constant diameter. After cooling for a period of time, the crystals are taken out of the growth furnace to diameter 207

, The length of certain diameter part is 64

Phosphorus silicon single crystal is obtained.

The in-plane distribution of oxygen concentration at each site of the crystal grown under such conditions was shown in FIG. 3 by FT-IR.

에서 시작하여 32

까지의 잉곳에서는 잉곳의 길이가 증가할수록 보다 낮은 산소 농도의 블록을 형성하며 전류의 값이 최고치인 32

일 때를 기점으로 하여 40

및 48

일 때는 잉곳의 길이가 증가할수록 높은 산소 농도의 블록을 형성한다. 그러나 56

일 때는 다시 산소의 농도가 감소된 블록을 형성한다. 이것은 성장 종료 직전에는 용융실리콘의 양이 감소하여 산소의 공급원인 석영도가니와의 접촉 면적이 감소하므로써 석영도가니에서 용해되는 산소량이 감소하며 또한 이로 인하여 자장 효과가 상대적으로 증가하기 때문이다.0 as shown in Figure 3

Starting at 32

Ingots up to 32 form a block of lower oxygen concentration as the length of the ingot increases, resulting in the highest current value of 32.

40 starting at

And 48

When the ingot increases in length to form a block of high oxygen concentration. But 56

When again, forms a block with reduced oxygen concentration. This is because the amount of molten silicon decreases immediately before the end of growth, and thus the amount of oxygen dissolved in the quartz crucible is reduced by decreasing the contact area with the quartz crucible, which is the source of oxygen, and the magnetic field effect is relatively increased.

Comparative Example 1

The same procedure as in Example 1 was performed except that the silicon single crystal was grown by using a general Czochralski method in which the magnetic field was not applied.

Comparative Example 2

In Example 1, the same procedure as in Example 1 was carried out except that silicon single crystals were grown by using the magnetic field-applied Czochralski method applied with the same magnetic field strength from the time of temperature stabilization.

10¹⁷개/

³이상의 산소 농도로 성장된 반면 자장인가 쵸크랄스키법만으로 성장된 경우에는 약 6.3

10¹⁷개/

³이하로 제어되고 있음을 알 수 있다. 반면에 본 발명에 의한 실리콘 단결정은 제3도의 결과로부터 0

25까지는 [0i]가 7

8

10¹⁷개/

³, 25

60까지는 5

6

10¹⁷개/

³인 두 가지 산소 농도 레벨을 갖는 구간이 형성되었음을 알 수 있다. 제5도와 비교하면 같은 세기의 자장인가인 경우, 본 발명에 의한 방법에서 보다 효율적으로 저 산소 농도 결정이 형성되며 중앙으로부터 90

이후의 길이에서는 보다 균일한 산소 농도 분포를 나타낸다.As a comparative example, Fig. 4 shows the Czochralski method, and Fig. 5 shows the oxygen concentration distribution of the crystal grown by the magnetic field applying Czochralski method applying the same magnetic field strength from the time of temperature stabilization. Single crystal grown by Czochralski method is 7

10 to ¹⁷ pcs /

About 6.3 when grown with oxygen concentration of ³ or more, but grown only with magnetic field or Czochralski method

10 to ¹⁷ pcs /

It can be seen that it is controlled to ³ or less. On the other hand, the silicon single crystal according to the present invention has a zero value from the result of FIG.

Until 25, [0i] is 7

8

10 to ¹⁷ pcs /

³ , 25

60 Up to 5

6

10 to ¹⁷ pcs /

It can be seen that a section with two oxygen concentration levels of ³ has been formed. Compared with FIG. 5, when the magnetic field of the same intensity is applied, low oxygen concentration crystals are formed more efficiently in the method according to the present invention.

The subsequent length shows a more uniform distribution of oxygen concentration.

10¹⁷개/

³부터 1

10¹⁸개/

³까지 임의의 범위에서 산소농도 제어가 가능하다. 또한 하나의 결정에서 2개 이상의 각각의 다른 산소 농도 스펙을 갖는 블록을 형성할 수 있으며, 자장인가에 요하는 전력비를 50

이상 절감하는 효과가 있다.According to the invention 3

10 to ¹⁷ pcs /

³ from 1

10 to ¹⁸ pcs /

Oxygen concentration can be controlled in any range up to ³ . It is also possible to form blocks with two or more different oxygen concentration specifications in a single crystal, which reduces the power ratio required to apply a magnetic field.

There is an effect to reduce over.

Claims (3)

Heat dissolving polycrystalline silicon to form a silicon solution, immersing seed crystals on the surface of the silicon solution, and raising seed crystals to grow silicon single crystals when the lower portion of the seed crystals begins to melt in the silicon solution. And a method of growing a silicon single crystal by applying a cusp magnetic field during the growth of the silicon single crystal, wherein the cusp magnetic field is not applied until a) a block of medium oxygen concentration is formed in the single crystal, b) after the formation of a block of medium oxygen concentration in the single crystal, the intensity of the magnetic field is gradually increased to a rate at which a uniform low oxygen concentration block can be formed, and after reaching the magnetic field strength to obtain a low oxygen concentration crystals The monocrystalline growth by gradually decreasing the intensity of the silicon oxide at a rate at which a uniform low oxygen concentration block can be formed It is to zero the intensity of a magnetic field immediately before the completion of the silicon single crystal growing method to form continuously a low oxygen concentration and a uniform block the oxygen concentration in the block of the grown single crystal. The method of claim 1, wherein the increase in the magnetic field strength of b) is 20 times the length of the single crystal

30

When, the current is 21.5A /

Increase in the ratio of b, and decrease in the magnetic field strength of b) the length of the single crystal is 30

50

Current is 6.1A /

Silicon single crystal growth method characterized in that for reducing the ratio of. Heating and dissolving polycrystalline silicon to form a silicon solution, immersing seed crystals on the surface of the silicon solution, and raising the seed crystals by growing the seed crystals when the lower portion of the seed crystals begins to melt in the silicon solution. In the step of applying a cusp magnetic field during growth of the silicon single crystal, wherein the cusp magnetic field is applied: a) a magnetic field is not applied until a block of medium oxygen concentration is formed in the single crystal. And b) gradually increasing the magnetic field strength at a rate at which a uniform low oxygen concentration block can be formed after the formation of the medium oxygen concentration block in the single crystal, and reaching the magnetic field strength for obtaining a low oxygen concentration crystal. The strength of the magnetic field is then gradually reduced to a rate at which a uniform low oxygen concentration block can be formed, whereby the single crystal The single crystal in the silicon single crystal manufactured by the silicon single crystal growing method which applies the magnetic field strength to zero just before the growth is completed to form a medium oxygen concentration block and a uniform low oxygen concentration block continuously in the grown single crystal. The length of 0

20

When the oxygen concentration is 7

8 to ¹⁷ pieces /

³ , the length of the single crystal is 25

60

When the oxygen concentration is 5

6 ^17pcs /

³ phosphorus silicon single crystal.

Images