JP2010030860A - Method for growing silicon single crystal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for growing a single crystal with stable quality without lowering the product yield when a silicon single crystal is made to grow by a continuous charging type of the HMCZ method. <P>SOLUTION: To a silicon melt 10 in a crucible 2 for pulling up a single crystal, while supplying a silicon melt to a second area R2 in an annular area R between a wall of the crucible 2 side and the outer circumference of a silicon single crystal 11 excluding a first area R1 extending to the direction perpendicular to the direction of application of the horizontal magnetic field from the outer circumference of the silicon single crystal 11, the single crystal 11 is made to grow. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for growing a silicon single crystal by the Czochralski method (hereinafter referred to as “CZ method”), and in particular, while applying a horizontal transverse magnetic field to the silicon melt in the crucible, the silicon melt in the crucible. The present invention relates to a method for growing a silicon single crystal by a continuous charge type transverse magnetic field application CZ method in which a silicon single crystal is pulled up and grown while sequentially supplying a liquid.

  A silicon single crystal is a material of a silicon wafer used for a semiconductor device, and a single crystal growing method by a CZ method is widely adopted for its production. Usually, in the growth of a silicon single crystal by the CZ method, a silicon raw material such as polycrystalline silicon filled as an initial charge in a quartz crucible is heated by a heater in a single crystal growth apparatus maintained in an inert gas atmosphere under reduced pressure. Heat to melt. When the silicon melt is formed in the quartz crucible, the seed crystal held on the pulling shaft is lowered above the quartz crucible and immersed in the silicon melt. From this state, while rotating the seed crystal and the quartz crucible in a predetermined direction, the seed crystal is gradually raised, whereby a silicon single crystal is grown and pulled below the seed crystal.

  In recent years, a pair of electromagnetic coils are arranged opposite to each other with a quartz crucible interposed therebetween, and a single magnetic crystal is grown while applying a transverse magnetic field to the silicon melt in the quartz crucible using the electromagnetic coil. , "HMCZ method"). The single crystal growth method by the HMCZ method can suppress the natural convection of the silicon melt by applying a transverse magnetic field, so it is possible to grow a single crystal in a thermal environment with little fluctuation, and control the oxygen concentration in the silicon single crystal. This is an effective method for producing a single crystal of stable quality. In particular, this method reduces the diameter fluctuation of the silicon single crystal under precise temperature control of the silicon melt and pulls it up while suppressing the speed fluctuation, and COP (Cristal Originated Particle) and dislocation clusters. It is suitably used for growing defect-free single crystals that do not have grown-in defects such as.

  On the other hand, since a silicon single crystal is a material of a silicon wafer, electrical characteristics are required as quality characteristics, and specific resistance is defined according to the application. For this reason, when growing a silicon single crystal, an appropriate amount of a dopant such as B (boron), P (phosphorus), As (arsenic), or Sb (antimony) is added to the crucible at an initial charge to obtain a silicon melt. The dopant concentration inside is adjusted, thereby adjusting the dopant concentration in the grown silicon single crystal and controlling the specific resistance.

  However, in the growth of the silicon single crystal, as the growth proceeds, the silicon melt remaining in the crucible decreases and the impurity element between the solid-phase silicon single crystal and the liquid-phase silicon melt. As a result of this segregation phenomenon, the dopant concentration in the silicon melt increases and the dopant concentration in the silicon single crystal also increases, so that there is a problem that the specific resistance of the single crystal gradually decreases.

  As a method for suppressing a decrease in the specific resistance of the silicon single crystal, there is a continuous charge type CZ method in which when a silicon single crystal is grown, a silicon melt or a solid silicon raw material is sequentially supplied to a crucible for pulling the single crystal. is there. In the continuous charge type CZ method, since the silicon melt or the solid silicon raw material is supplied to the crucible during the growth of the single crystal, the dopant concentration in the silicon melt in the crucible can be kept almost constant. Thereby, the dopant concentration in the silicon single crystal becomes substantially constant, and the specific resistance of the single crystal can be made uniform.

  Here, when supplying a solid silicon raw material to the crucible, temperature fluctuations are likely to occur in the silicon melt in the crucible, and there is a concern about the quality deterioration of the silicon single crystal to be grown. Is more practical.

  Regarding a technique for growing a silicon single crystal by a continuous charge type CZ method, Patent Document 1 discloses that during the growth of a single crystal, a silicon melt is passed through a protective cylinder in which a tip is immersed in a raw material melt filling region of a crucible. A single crystal growing apparatus to be supplied has been proposed. In Patent Document 2, a partition wall higher than the surface of the silicon melt is provided concentrically on the inner side of the crucible, and a single crystal is pulled up inside the partition wall while the partition wall and the side wall of the crucible are interposed. There has been proposed a single crystal growth apparatus for supplying a silicon melt to the inside of the partition wall through holes formed in the lower part of the partition wall.

  However, when a single crystal growth apparatus proposed in Patent Document 1 is used to grow a silicon single crystal while applying a transverse magnetic field, depending on the supply position of the silicon melt to the crucible, Single crystal diameter fluctuations and pulling speed fluctuations remarkably occurred, resulting in a decrease in product yield.

  In addition, when the single crystal growth apparatus proposed in Patent Document 2 is used to grow a single crystal while applying a transverse magnetic field, the diameter and pulling speed of the silicon single crystal are stable during the single crystal growth. However, since the partition wall installed on the inner side of the crucible is made of quartz, oxygen is eluted from the partition wall as well as the inner surface of the crucible into the silicon melt in the crucible. For this reason, the amount of oxygen eluted in the silicon melt in the crucible increases, the oxygen concentration in the silicon single crystal exceeds the standard, and the product yield decreases. In addition, in the single crystal growing apparatus proposed in Patent Document 2, since the partition walls are installed inside the crucible, the manufacturing cost of the crucible is deteriorated.

JP-A-2-279582 JP 52-58080 A

  The present invention has been made in view of the above-mentioned problems, and restricts the supply position of the silicon melt to the crucible within a specific range when growing a silicon single crystal by a continuous charge type HMCZ method. Accordingly, an object of the present invention is to provide a method for growing a silicon single crystal that can grow a stable quality silicon single crystal without reducing the product yield.

  In order to achieve the above object, the inventors of the present invention, in the growth of a single crystal by a continuous charge type HMCZ method, without providing a partition inside the crucible, depending on the position of the silicon melt supplied to the crucible, Paying attention to the difference in the degree of occurrence of diameter fluctuation and pulling speed fluctuation, the generation mechanism was examined in detail. As a result, it has been found that fluctuations in the diameter of the silicon single crystal and fluctuations in the pulling speed are caused by the flow of the silicon melt in the crucible that occurs with the application of the transverse magnetic field.

  FIG. 1 is a diagram schematically showing the flow of a silicon melt in a crucible in the HMCZ method. FIG. 1A is a perspective view, and FIG. 1B is a plan view. The flow of silicon melt in the crucible in the HMCZ method is a pair perpendicular to the direction of application of the transverse magnetic field on both sides of the center line of the transverse magnetic field indicated by the thick arrow in FIG. 1, as indicated by the solid arrow in FIG. It becomes a roll-like flow. These roll-shaped flows are convection symmetric with respect to the center line of the transverse magnetic field, and are directed toward the center line side of the transverse magnetic field in the vicinity of the surface of the silicon melt.

  Then, in the annular region R between the side wall of the crucible in the silicon melt in the crucible and the outer periphery of the silicon single crystal (the hatched portion and the cross-hatched portion in FIG. 1B), it extends from the outer periphery of the silicon single crystal. When the silicon melt adjusted to the high temperature state is supplied to the first region R1 (hatched portion in FIG. 1B) extending in the direction orthogonal to the direction in which the magnetic field is applied, the high temperature melt is contained in the crucible. The silicon melt flows in the direction in which the silicon single crystal exists due to the convection of the silicon melt and reaches the crystal growth interface. As a result, the melt temperature at the crystal growth interface locally fluctuates, and accompanying this, fluctuations in the diameter of the single crystal and fluctuations in the pulling speed appear.

  On the other hand, when a high-temperature silicon melt is supplied to the second region R2 (cross-hatched portion in FIG. 1B) excluding the first region R1 in the annular region R, the high-temperature melt The liquid flows only in the direction in which no silicon single crystal exists due to the convection of the silicon melt in the crucible, and does not reach the crystal growth interface. As a result, the melt temperature at the crystal growth interface does not fluctuate locally, and the fluctuation of the diameter of the single crystal and the fluctuation of the pulling rate can be suppressed.

  The present invention has been completed based on such findings, and the gist thereof is the following method for growing a silicon single crystal. That is, a pair of electromagnetic coils are arranged opposite each other with a crucible in between, and a silicon single crystal is grown by the CZ method while applying a transverse magnetic field to the silicon melt in the crucible while supplying the silicon melt into the crucible. In the annular region between the side wall of the crucible and the outer periphery of the silicon single crystal in the silicon melt in the crucible, the method extends from the outer periphery of the silicon single crystal in a direction orthogonal to the direction in which the transverse magnetic field is applied. A silicon single crystal growth method characterized in that a silicon melt is supplied to a second region excluding the first region.

  In this growth method, it is preferable to supply the silicon melt to the second region through the melt supply tube by immersing the tip of the melt supply tube in the silicon melt of the second region.

  According to the silicon single crystal growth method of the present invention, since the silicon melt is supplied to the silicon melt in the crucible within the range of the second region, it is not necessary to provide a partition inside the crucible. The high-temperature melt supplied into the crucible does not reach the crystal growth interface due to the convection of the silicon melt that occurs with the application of the transverse magnetic field. Therefore, the melt temperature at the crystal growth interface does not fluctuate locally, so that fluctuations in the diameter of the single crystal and fluctuations in the pulling rate can be suppressed, and stable quality silicon singles can be obtained without lowering the product yield. It becomes possible to grow crystals.

Below, the embodiment is explained in full detail about the growth method of the silicon single crystal of the present invention.
FIG. 2 is a diagram schematically showing a configuration of a single crystal growth apparatus suitable for growing a silicon single crystal by a continuous charge type HMCZ method according to an embodiment of the present invention. As shown in FIG. 2, the single crystal growing apparatus is configured with a chamber 1 at its outer periphery, and a crucible 2 for pulling a single crystal is disposed in the center of the chamber 1. The crucible 2 has a double structure, and is composed of an inner quartz crucible 2a and an outer graphite crucible 2b. The crucible 2 is fixed to the upper end portion of the support shaft 3, and can rotate in the circumferential direction and can be lifted and lowered in the axial direction through the rotational drive and lift drive of the support shaft 3.

  A resistance heating heater 4 surrounding the crucible 2 is disposed outside the single crystal pulling crucible 2, and a heat insulating material 5 is disposed along the inner surface of the chamber 1 further outside. The heater 4 melts the solid silicon raw material filled in the crucible 2, whereby a silicon melt 10 is formed in the crucible 2.

  A pulling shaft 6 such as a wire is arranged coaxially with the support shaft 3 above the single crystal pulling crucible 2. The pulling shaft 6 can be moved up and down by rotating by a pulling mechanism (not shown) provided at the upper end of the chamber 1. A seed crystal 7 is attached to the tip of the pulling shaft 6. As the pulling shaft 6 is driven, the seed crystal 7 is immersed in the silicon melt 10 in the crucible 2, and the seed crystal 7 is gradually raised while rotating, whereby a silicon single crystal is formed below the seed crystal 7. 11 is nurtured.

  Further, a cylindrical heat shield 8 surrounding the silicon single crystal 11 being pulled is disposed in the chamber 1. The heat shield 8 serves to block the radiant heat from the silicon melt 10 and the heater 4 in the single crystal pulling crucible 2 and promote the cooling of the silicon single crystal 11 being pulled.

  In addition, a pair of electromagnetic coils 9 facing each other with the single crystal pulling crucible 2 in between are disposed outside the chamber 1. The electromagnetic coil 9 generates a horizontal transverse magnetic field between the electromagnetic coils 9 and applies the transverse magnetic field to the silicon melt 10 in the crucible 2. The application of a transverse magnetic field suppresses natural convection of the silicon melt 10 and suppresses rapid fluctuations in the melt temperature at the crystal growth interface, so that a high-quality silicon single crystal 11 that does not cause dislocation or fluctuation in diameter is generated. Can be nurtured.

  The single crystal growth apparatus shown in FIG. 2 includes a melt supply apparatus 20 that sequentially supplies silicon melt to the crucible 2 for pulling up a single crystal in the process of growing the silicon single crystal 11. The melt supply apparatus 20 of the present embodiment is configured as follows.

  As shown in FIG. 2, a raw material melting crucible 21 is disposed in the chamber 1 above the single crystal pulling crucible 2 at a position deviating from the central axis of the crucible 2. The raw material melting crucible 21 includes a water-cooled crucible 22 made of a metal having excellent thermal conductivity and conductivity, such as copper, and a quartz crucible 23 arranged inside the water-cooled crucible 22.

  The water-cooled crucible 22 is divided into a plurality of segments in the circumferential direction, and is cooled by heat exchange with cooling water that circulates inside. The cooling water is introduced into the water-cooled crucible 22 through a water supply pipe (not shown), passes through a flow path (not shown) formed in the water-cooled crucible 22 itself, and is discharged outside through a drain pipe (not shown). A quartz melt outflow pipe 24 extending in the vertical direction is connected to the bottom of the quartz crucible 23, and the melt outflow pipe 24 passes through the bottom of the water-cooled crucible 22.

  An induction heating coil 25 surrounding the crucible 21 is provided around the raw material melting crucible 21 composed of the water-cooled crucible 22 and the quartz crucible 23. The induction heating coil 25 is connected to a power supply device via a wiring (not shown), and an alternating current is applied from the power supply device.

  Above the raw material melting crucible 21, a raw material supply pipe 26 made of quartz is provided. The raw material supply pipe 26 passes through the chamber 1, and a raw material feeder (not shown) is connected to the upper end thereof, and the lower end thereof is disposed inside the quartz crucible 23. A solid silicon raw material is introduced into the raw material supply pipe 26 from the raw material feeder, and the silicon raw material can be supplied to the raw material melting crucible 21 through the raw material supply pipe 26.

  Below the raw material melting crucible 21, a quartz melt supply pipe 27 is disposed coaxially with the melt outflow pipe 24 from the quartz crucible 23. The melt supply pipe 27 has an upper end that opens toward the lower end of the melt outflow pipe 24, and a lower end of the melt supply pipe 27 near the inner side of the side wall of the single crystal pulling crucible 2 to the silicon melt 10 in the crucible 2. Configured to soak.

  In the melt supply device 20 configured as described above, the solid silicon raw material is supplied to the quartz crucible 23 through the raw material supply pipe 26, and an alternating current is applied to the induction heating coil 25, whereby the inner side of the induction heating coil 25. A magnetic field is formed. Due to this magnetic field, an eddy current is generated in the solid silicon raw material in the quartz crucible 23, and the solid silicon raw material is heated by Joule heat generated by the eddy current. As a result, the solid silicon raw material can be melted in the quartz crucible 23 to form the silicon melt 30.

  Further, the formed silicon melt 30 receives a levitation force by the action of electromagnetic force due to eddy currents generated on the inner surface of the water-cooled crucible 22 and eddy currents generated on the surface of the silicon melt 30. The silicon melt 30 in the quartz crucible 23 is maintained in contact with the quartz crucible 23 while being held at that position due to the balance between the levitation force and the weight of the silicon melt itself.

  In this state, by supplying the solid silicon raw material from the raw material supply pipe 26 to the quartz crucible 23, the silicon melt 30 held in the quartz crucible 23 has an amount of silicon corresponding to the supply amount of the solid silicon raw material. The melt 30 flows out from the quartz crucible 23 through the melt outflow pipe 24. The silicon melt 30 that has flowed out is supplied to the crucible 2 for pulling up the single crystal through the melt supply pipe 27.

  At this time, the solid silicon raw material supplied to the quartz crucible 23 rises in temperature by coming into contact with the silicon melt 30 existing in the quartz crucible 23 and is easily melted by electromagnetic induction from the induction heating coil 25.

  FIG. 3 is a schematic view showing a supply position of the silicon melt into the crucible for pulling a single crystal in the present invention. As shown in the figure, the silicon melt 10 in the crucible 2 for growing a single crystal is an annular region R between the side wall of the crucible 2 and the outer periphery of the silicon single crystal 11 (the hatched portion and the cross-hatching in FIG. 3). Part).

  In the present invention, the annular region R is divided into a first region R1 (hatched portion in FIG. 3) and a second region R2 (cross-hatched portion in FIG. 3), and silicon fusion is performed only in the second region R2. The liquid supply is allowed. The first region R <b> 1 is a region extending from the outer periphery of the silicon single crystal 11 in a direction orthogonal to the application direction of the transverse magnetic field, and its width W is the same as the diameter D of the silicon single crystal 11. That is, the first region R1 is a region that sandwiches the silicon single crystal 11 in a direction orthogonal to the application direction of the transverse magnetic field. The second region R2 is a region excluding the first region R1, and is a region that sandwiches the silicon single crystal 11 in the direction in which the transverse magnetic field is applied.

  FIG. 3 shows a state in which the melt supply pipe 27 for supplying the silicon melt into the crucible 2 is arranged at a position corresponding to the center line of the transverse magnetic field in the second region R2. In this range, the melt supply pipe 27 is disposed. In particular, it is desirable to arrange the melt supply pipe 27 in the vicinity of the side wall portion of the crucible 2 near the arrangement position of the transverse magnetic field device within the range of the second region R2.

  Thus, in the structure which arrange | positions the melt supply pipe | tube 27 in the range of 2nd area | region R2 with respect to the silicon melt 10 in the crucible 2 for single crystal growth, and supplies the silicon melt of a high temperature state, it is the above-mentioned. As described above, the high-temperature melt supplied into the crucible 2 flows only in the direction in which no silicon single crystal exists due to the convection of the silicon melt 10 in the crucible 2 generated by the application of the transverse magnetic field, and the crystal growth interface. Never reach. As a result, the melt temperature at the crystal growth interface does not fluctuate locally, and the fluctuation of the diameter of the single crystal and the fluctuation of the pulling rate can be suppressed.

  Moreover, in the present invention, it is not necessary to provide a quartz partition as described in Patent Document 2 inside the crucible 2 for growing a single crystal, so that the oxygen concentration in the silicon single crystal becomes excessively high. Things don't happen.

  Therefore, according to the method for growing a silicon single crystal of the present invention, it is possible to grow a silicon single crystal having a stable quality without reducing the product yield.

  Further, in the above-described single crystal growth apparatus, the tip of the melt supply pipe 27 is immersed in the silicon melt 10 in the single crystal growth crucible 2, so that the silicon melt 10 is deposited on the supply melt. As a result, scattering and undulation can be prevented, and the quality of the silicon single crystal to be grown can be further stabilized.

  In the melt supply apparatus 20 described above, the raw material melting crucible 21 is composed of the quartz crucible 23 and the water-cooled crucible 22, and the silicon melt is supplied to the single crystal growth crucible 2 through the melt supply pipe 27. However, as long as it is possible, instead of the water-cooled crucible 22, a heat insulating material having low conductivity may be adopted.

  In order to confirm the effect of the method for growing a silicon single crystal of the present invention, the following test was conducted. Using the single crystal growth apparatus shown in FIG. 2, a single crystal pulling crucible having an inner diameter of 32 inches is used, and 200 kg of granular polycrystalline silicon is initially charged and melted as a silicon raw material from this silicon melt. A silicon single crystal having a length of 1000 mm was grown. The growth conditions were a transverse magnetic field strength of 3000 gauss, a single crystal pulling crucible rotation speed of 1 rpm, and a pulling shaft rotation speed of 8 rpm.

  At that time, an alternating current having a frequency of 30 kHz is applied to the induction heating coil at a power of 56 kW to melt the solid silicon raw material in the raw material melting crucible, and the liquid surface position of the silicon melt in the single crystal pulling crucible is constant. Thus, silicon melt was sequentially supplied. This melt supply was performed using a melt supply pipe having an inner diameter of 40 mm, with the tip end immersed in a silicon melt in a single crystal pulling crucible for 50 mm.

  In the test of Example 1, the supply position of the silicon melt to the single crystal pulling crucible, that is, the position where the melt supply pipe is arranged is changed to four points A to D shown in FIG. A silicon single crystal was grown while supplying a silicon melt at each point of D.

  FIG. 4 is a schematic diagram illustrating the supply position of the silicon melt employed in the test of Example 1. As shown in the figure, points A and B within the range of the second region R2 are the melt supply positions adopted as examples of the present invention, and points C and D within the range of the first region R1 are It is a melt supply position adopted as a comparative example.

  Then, in the process of growing the silicon single crystal while supplying the melt at each point of A to D, the fluctuation of the diameter of the single crystal and the fluctuation of the pulling rate were evaluated. Specifically, the diameter of the single crystal is measured for every 20 mm pulling length in the range of 300 to 800 mm of the crystal pulling length where the operation is stable, and the diameter variation of the single crystal is measured by the amount of deviation of the measured diameter from the target diameter. evaluated. Similarly, the average pulling speed was calculated for a pulling length of 10 mm within the range of 300 to 800 mm for the crystal pulling length, and the fluctuation of the pulling speed was evaluated by the ratio of the calculated speed to the target pulling speed.

  FIG. 5 is a diagram showing the results of the diameter variation of the silicon single crystal by the test of Example 1. FIG. As shown in the figure, in the example of the present invention in which the melt supply position is point A and B (within the range of the second region R2), the melt supply position is point C and D (the range of the first region R1). The variation in the diameter of the single crystal was clearly suppressed as compared with the comparative example.

  FIG. 6 is a diagram showing the results of fluctuations in the pulling speed according to the test of Example 1. As shown in the figure, in the example of the present invention in which the melt supply positions are the points A and B, the fluctuation of the pulling speed is remarkably suppressed as compared with the comparative example in which the melt supply positions are the points C and D. It was sufficiently ensured within a range of ± 5% with respect to the target pulling speed.

  In the test of this Example 2, with the intention of growing defect-free single crystals, the pulling speed was changed to a low speed with respect to the test conditions of Example 1 above, and from the melt surface in the single crystal pulling crucible. The single crystal was grown two by two while changing the distance to the lower end of the heat shield and supplying the melt at each of the above points A to D. Then, for each grown single crystal, the ratio of the region that actually became defect-free to the region of the crystal pulling length that should be defect-free was evaluated. The results are shown in Table 1 below.

  As shown in the table, in the example of the present invention in which the melt supply positions are the points A and B, the proportion of the defect-free region is markedly higher than in the comparative example in which the melt supply positions are the points C and D. Improved.

  In the test of Example 3, a crucible for growing a single crystal provided with a quartz partition as described in Patent Document 2 was used as a comparative example in the test of Example 1 described above. At that time, a single crystal was grown by setting the melt supply position between the partition wall and the side wall of the crucible and corresponding to the above point A. Then, for each of the single crystal of the present invention grown while supplying the melt at point A and the single crystal of the comparative example, sample wafers were collected over the entire pulling direction, and oxygen at the center of each sample wafer was collected. Concentration was measured. The results are shown in Table 2 below.

  As shown in the table, in the present invention example in which the melt supply position is point A, the oxygen concentration was significantly reduced as compared with the comparative example using a crucible having a partition wall.

  According to the silicon single crystal growth method of the present invention, the silicon melt in the crucible for single crystal growth is supplied to the silicon melt within the range of the second region. Even if the temperature is not provided, the high-temperature melt supplied into the crucible does not reach the crystal growth interface due to the convection of the silicon melt generated with the application of the transverse magnetic field. Therefore, the melt temperature at the crystal growth interface does not fluctuate locally, and it is possible to suppress fluctuations in the diameter of the single crystal and fluctuations in the pulling speed, resulting in stable quality without lowering the product yield. It becomes possible to grow a silicon single crystal.

It is a figure which shows typically the flow of the silicon melt in a crucible in HMCZ method, The perspective view is the same figure, (b) shows a top view, respectively. It is a figure which shows typically the structure of the single-crystal growth apparatus suitable for the growth of the silicon single crystal by the continuous charge system HMCZ method which is one Embodiment of this invention. It is a schematic diagram which shows the supply position of the silicon melt into the crucible for single crystal pulling in this invention. FIG. 3 is a schematic diagram showing a silicon melt supply position employed in the test of Example 1. FIG. 3 is a diagram showing the result of the diameter variation of a silicon single crystal by the test of Example 1. It is a figure which shows the result of the fluctuation | variation of the raising speed by the test of Example 1. FIG.

Explanation of symbols

1: chamber, 2: crucible for pulling single crystal, 2a: quartz crucible,
2b: graphite crucible, 3: support shaft, 4: heater, 5: heat insulating material,
6: Lifting shaft, 7: Seed crystal, 8: Thermal shield, 9: Electromagnetic coil,
10: Raw material melt, 11: Silicon single crystal,
20: Melt supply device, 21: Crucible for melting raw material, 22: Water-cooled crucible,
23: Quartz crucible, 24: Melt outflow pipe, 25: Induction heating coil,
26: Raw material supply pipe, 27: Melt supply pipe, 30: Silicon melt

Claims (2)

A pair of electromagnetic coils are placed opposite each other with a crucible in between, and a silicon single crystal is grown by the Czochralski method while applying a transverse magnetic field to the silicon melt in the crucible while supplying the silicon melt into the crucible. A way to
Of the annular region between the side wall of the crucible and the outer periphery of the silicon single crystal in the silicon melt in the crucible, the first region excluding the first region extending from the outer periphery of the silicon single crystal in the direction perpendicular to the direction in which the transverse magnetic field is applied. A method for growing a silicon single crystal, comprising supplying silicon melt to two regions.   2. The supply of the silicon melt to the second region is performed by immersing the tip of the melt supply tube in the silicon melt of the second region and through the melt supply tube. For growing silicon single crystals.

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