JP6922831B2 - Silicon single crystal manufacturing method and silicon single crystal pulling device - Google Patents

Description

The present invention relates to a method for producing a silicon single crystal and a device for pulling a silicon single crystal.

When used as a semiconductor wafer, the high concentration of carbon in a silicon single crystal causes semiconductor device defects.
Here, the carbon concentration in the crystal is determined by controlling the contamination rate of CO mixed in the raw material melt from a high-temperature carbon member such as a heater in a furnace and a graphite crucible, and the evaporation rate of CO from the raw material melt. It is known to reduce. CO (gas) from the high temperature carbon member is generated based on the following reaction formula (1).
SiO (gas) + 2C (solid) → CO (gas) + SiC (solid) ... Equation (1)

Therefore, Patent Document 1 discloses a technique for discharging the CO-containing gas existing in the quartz crucible from below the heater of the pulling device.
Further, in Patent Document 2, an inert gas such as argon gas is introduced into the quartz crucible from above the pulling device, and the gas containing CO is guided above the upper end and below the lower end of the heater to guide the pulling device. The technology for discharging from below is disclosed.

Japanese Patent No. 4423805 Japanese Unexamined Patent Publication No. 05-319976

However, although the technique described in Patent Document 1 has a general exhaust structure, it can exhaust only in the lower part of the furnace, so that there is a problem that the CO gas generated in the upper part of the furnace cannot be efficiently discharged. be.
Further, in the technique described in Patent Document 2, when a plurality of exhaust paths are provided in the hot zone in one system exhaust, the exhaust at a location near the exhaust port on the device side becomes predominant, and thus the exhaust at a location far from the exhaust port on the device side becomes predominant. However, the exhaust efficiency is reduced due to the influence of piping resistance. Therefore, there is a problem that a sufficient effect cannot be obtained even if a plurality of exhaust ports are provided.

An object of the present invention is to provide a method for producing a silicon single crystal and a device for pulling up the silicon single crystal, which can efficiently exhaust a gas containing CO to reduce the carbon concentration in the silicon single crystal. ..

The method for producing a silicon single crystal of the present invention uses a pulling device provided with a chamber, a quartz crucible provided in the chamber, and a heater arranged so as to surround the quartz crucible and heating the quartz crucible. A method for producing a silicon single crystal, which comprises producing a silicon single crystal, wherein the gas introduced into the pulling device during pulling is exhausted from the back surface of the heater.

Here, the back surface of the heater means a region where the heater is projected in the horizontal direction from the back surface of the heater toward the inner cylinder.
As described above, the SiO gas generated from the high-temperature carbon member such as a heater and the silicon melt reacts as in the formula (1) to generate CO gas. When this CO gas is mixed in the silicon melt, the carbon concentration in the silicon single crystal increases.
Basically, the higher the temperature of the carbon member, the easier it is for CO gas to be generated by the reaction of the formula (1). The heater, which is the carbon member having the highest temperature among the members in the furnace, generates the largest amount of CO gas. Therefore, by exhausting from the back surface of the heater, which is the site where CO gas is generated, the CO gas can be exhausted in the shortest path, so that the carbon concentration in the silicon single crystal can be reduced.

In the present invention, it is preferable that the exhaust port for exhausting air from the back surface of the heater is formed at a position where it overlaps at least a part of the back surface of the heater.
According to the present invention, if the exhaust port is formed at a position where it overlaps with at least a part of the back surface of the heater, the CO gas generated from the upper surface of the heater or the lower surface of the lower part of the heater can be exhausted. The carbon concentration can be reduced.

In the present invention, the heaters have a plurality of first heating portions, each of which extends in the vertical direction and is arranged with a gap in the width direction orthogonal to the vertical direction, and the upper end of each of the plurality of first heating portions. It is provided with a second heating portion that alternately connects each other and the lower ends of each, and is formed in a meandering shape, and an exhaust port that exhausts from the back surface of the heater overlaps at least a part of the back surface of the first heating portion. It is preferably formed at the position.
According to the present invention, if the exhaust port is formed at a position where it overlaps at least a part of the back surface of the first heating portion, CO gas can be exhausted from the gap between the first heating portions, so that the CO gas can be exhausted in the silicon single crystal. The carbon concentration can be reliably reduced.

In the present invention, the exhaust port that exhausts air from the back surface of the heater is between the second heating unit that connects the upper ends of the first heating unit and the second heating unit that connects the lower ends of the first heating unit. It is preferably formed in.
According to the present invention, the CO gas generated by the heater can be directly exhausted from the gap between the first heating portions 51 of the heater. Therefore, the CO gas generated by the heater 5 can be more reliably exhausted, and the carbon concentration in the raised silicon single crystal can be reduced.

In the present invention, it is preferable that the exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping the back surface of the first heating unit.
According to the present invention, the CO gas can be reliably exhausted from the slit-shaped gaps between the plurality of first heating portions arranged in the width direction of the heater, so that the CO gas is exhausted in the shortest path from the CO gas generation position. Therefore, the carbon concentration in the silicon single crystal can be reduced more reliably.

In the present invention, it is conceivable that the gas introduced into the pulling device is further exhausted from above the upper end of the heater.
Further, in the present invention, it is conceivable that the gas introduced into the pulling device is further exhausted from below the lower end of the heater.
According to these inventions, even when the exhaust is only above the upper end of the heater or only below the lower end of the heater, by adding the exhaust on the back side of the heater, from the vicinity of the CO gas generation site. Since CO gas can be exhausted, the carbon concentration in the silicon single crystal can be reduced.

In the present invention, it is preferable that the pulling device includes an exhaust duct arranged outside the heater, and the exhaust duct includes a central exhaust port formed at a position corresponding to the back surface of the heater.
According to the present invention, if the exhaust duct is arranged outside the heater, the CO gas generated from the heater can be efficiently exhausted, so that the CO gas is mixed in the silicon melt and is contained in the silicon single crystal. It is possible to prevent the carbon concentration from increasing.
In particular, if there are a plurality of exhaust ducts and the exhaust ducts are evenly arranged in the circumferential direction of the heater, CO gas can be exhausted from even positions in the circumferential direction of the heater. Therefore, the carbon-containing gas incorporated into the silicon single crystal is evenly exhausted around the crystal axis of the silicon single crystal. Further, since each exhaust duct is provided with a central exhaust port, efficient exhaust can be performed, and the carbon concentration in the silicon single crystal can be further reduced.

The silicon single crystal pulling device of the present invention includes a chamber, a quartz crucible provided in the chamber, a heater arranged so as to surround the quartz crucible and heating the quartz crucible, and in the chamber during pulling. It is characterized by including an exhaust port for exhausting the introduced gas from the back surface of the heater.

In the present invention, it is preferable that the exhaust port for exhausting air from the back surface of the heater is formed at a position where it overlaps with at least a part of the back surface of the heater.
In the present invention, the heaters have a plurality of first heating portions, each of which extends in the vertical direction and is arranged with a gap in the width direction orthogonal to the vertical direction, and the upper end of each of the plurality of first heating portions. It is provided with a second heating portion that alternately connects each other and the lower ends of each, and is formed in a meandering shape, and an exhaust port that exhausts from the back surface of the heater overlaps at least a part of the back surface of the first heating portion. It is preferably formed at the position.

In the present invention, the exhaust port that exhausts air from the back surface of the heater is between the second heating unit that connects the upper ends of the first heating unit and the second heating unit that connects the lower ends of the first heating unit. It is preferably formed in.
In the present invention, it is preferable that the exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping the back surface of the first heating unit.
In the present invention, it is preferable to provide a heat shield provided above the quartz crucible and shield the heat from the silicon melt in the quartz crucible.
With these inventions, the same actions and effects as those described above can be enjoyed.

The schematic diagram which shows the structure of the silicon single crystal pulling apparatus which concerns on embodiment of this invention. FIG. 5 is a vertical cross-sectional view showing the structure of the exhaust flow path according to the embodiment. The horizontal sectional view which shows the structure of the exhaust flow path in the said Embodiment. The schematic diagram which shows the structure of the heater and the arrangement range of the central exhaust port in the said Embodiment. FIG. 5 is a vertical cross-sectional view showing the structure of an exhaust flow path according to a second embodiment of the present invention. The graph which shows the change of the carbon concentration in a silicon single crystal in an Example and a comparative example. Vertical cross-sectional view showing the exhaust port position by simulation. The graph which shows the simulation result at each exhaust port position.

[1] Structure of the Silicon Single Crystal Pulling Device 1 FIG. 1 shows a schematic view showing an example of the structure of the silicon single crystal pulling device 1 to which the method for manufacturing the silicon single crystal 10 according to the embodiment of the present invention can be applied. There is. The pulling device 1 is a device for pulling the silicon single crystal 10 by the Czochralski method, and includes a chamber 2 forming an outer shell and a crucible 3 arranged in the center of the chamber 2.
The crucible 3 has a double structure composed of an inner quartz crucible 3A and an outer graphite crucible 3B, and is fixed to the upper end of a support shaft 4 capable of rotating and raising and lowering.

A resistance heating type heater 5 surrounding the crucible 3 is provided on the outside of the crucible 3, and a heat insulating material 6 serving as an outer cylinder is provided on the outside of the heater 5 along the inner surface of the chamber 2.
Above the crucible 3, a pull-up shaft 7 such as a wire that rotates coaxially with the support shaft 4 in the opposite direction or the same direction at a predetermined speed is provided. A seed crystal 8 is attached to the lower end of the pulling shaft 7.

A tubular heat shield 12 is arranged in the chamber 2.
The heat shield 12 blocks high-temperature radiant heat from the silicon melt 9 in the crucible 3, the heater 5, and the side wall of the crucible 3 with respect to the growing silicon single crystal 10, and is a solid liquid that is a crystal growth interface. In the vicinity of the interface, it suppresses the diffusion of heat to the outside and plays a role of controlling the temperature gradient in the pulling axial direction of the central portion of the single crystal and the outer peripheral portion of the single crystal.
Further, the heat shield 12 also has a function as a rectifying cylinder that exhausts the evaporation part from the silicon melt 9 to the outside of the furnace by the inert gas introduced from above the furnace.

A gas introduction port 13 for introducing an inert gas such as argon gas (hereinafter referred to as Ar gas) into the chamber 2 is provided in the upper part of the chamber 2. An exhaust port 14 is provided in the lower part of the chamber 2 to suck and discharge the gas in the chamber 2 by driving a vacuum pump (not shown).
The inert gas introduced into the chamber 2 from the gas introduction port 13 descends between the growing silicon single crystal 10 and the heat shield 12, and the lower end of the heat shield 12 and the liquid level of the silicon melt 9. After passing through the gap between the two, the gas flows toward the outside of the heat shield 12 and further toward the outside of the rutsubo 3, and then descends from the central exhaust port 16A, which will be described later, to the outside of the rutsubo 3 via the exhaust duct 15, and the exhaust port 14 Is discharged from.

When the silicon single crystal 10 is produced using such a pulling device 1, the heater 5 uses a solid raw material such as polycrystalline silicon filled in the crucible 3 while maintaining the inside of the chamber 2 in an inert gas atmosphere under reduced pressure. Is melted by heating to form a silicon melt 9. When the silicon melt 9 is formed in the crucible 3, the pulling shaft 7 is lowered to immerse the seed crystal 8 in the silicon melt 9, and the crucible 3 and the pulling shaft 7 are rotated in a predetermined direction while the pulling shaft is rotated. 7 is gradually pulled up, thereby growing a silicon single crystal 10 connected to the seed crystal 8.

[2] Structure of the exhaust flow path FIG. 2 and FIG. 3 show the structure of the exhaust flow path formed in the above-mentioned pulling device 1. FIG. 2 is a vertical sectional view, and FIG. 3 is a horizontal sectional view.
As shown in FIG. 3, the exhaust duct 15 is composed of a long member having a U-shaped cross section, and the U-shaped flange tip of the exhaust duct 15 is joined to an inner cylinder 16 arranged outside the heater 5. .. The exhaust ducts 15 are provided at four locations on the outside of the heater 5 in the circumferential direction of the inner cylinder 16. The pair of exhaust ducts 15 facing each other and the other pair of exhaust ducts 15 are evenly arranged so as to form an angle of 90 ° in a plan view shown in FIG.

The inner cylinder 16 is a cylindrical body made of a carbon member such as graphite. As shown in FIG. 2, the inner cylinder 16 is formed with a central exhaust port 16A on the back surface of the heater 5.
In the present embodiment, the exhaust ducts 15 are provided at four locations, but the present invention is not limited to this, and the exhaust ducts 15 may be provided at three locations or eight locations, as long as there are a plurality of exhaust ducts 15.

As shown in FIG. 4, the heater 5 includes a first heating unit 51, a second heating unit 52, and 53, the upper end of the first heating unit 51 is the second heating unit 52, and the lower end of the first heating unit is the second. The two heating portions 53 are alternately connected to form a meandering shape extending in the width direction.
The first heating unit 51 is composed of a rod-shaped body or a plate-shaped body made of carbon which is a resistance heating body extending vertically, and a plurality of first heating portions 51 are arranged with a gap in the width direction orthogonal to the vertical direction.

The second heating unit 52 is composed of a carbon rod-shaped body or a plate-shaped body extending in the horizontal direction, and connects the upper ends of the first heating unit 51 adjacent to each other in the width direction every other time.
The second heating unit 53 is composed of a carbon rod-shaped body or a plate-shaped body extending in the horizontal direction, and connects the lower ends of the first heating unit 51 adjacent to each other in the width direction every other time.
That is, in the heater 5, the first heating unit 51 is arranged with a gap in the width direction, and the upper ends of the first heating unit 51 are connected to each other by the second heating unit 52, and the first heating unit 51 By connecting the lower ends to each other at a position different from the upper portion by the second heating portion 53, the lower ends are formed in a meandering shape.

As shown in FIG. 4, the central exhaust port 16A can be arranged within the range H2 of the back surface of the heater 5 in the height direction. The range H2 is a range in which at least a part of the middle exhaust port 16A is included in the height range H0 between the upper end of the second heating unit 52 and the lower end of the second heating unit 53 in the height direction of the heater 5. Is.
If the central exhaust port 16A is formed in the range H2 in the height direction, at least exhaust from the back surface of the heater 5 becomes possible. Therefore, since the CO gas generated by the heater 5 can be exhausted from the back surface of the heater 5, the carbon concentration in the raised silicon single crystal 10 can be reduced.

More preferably, the central exhaust port 16A is arranged in the height range H0 between the upper end of the second heating portion 52 of the heater 5 and the lower end of the second heating portion 53.
If the central exhaust port 16A is formed in the height range H0, the CO gas generated by the heater 5 can be directly exhausted from the gap between the first heating portions 51 of the heater 5. Therefore, the CO gas generated by the heater 5 can be more reliably exhausted, and the carbon concentration in the raised silicon single crystal 10 can be reduced.

Most preferably, as shown in FIG. 4, the central exhaust port 16A is arranged in the height range H1 of the gap formed between the adjacent first heating portions 51.
If the central exhaust port 16A is formed in the range H1 in the height direction, the amount of exhaust gas from the gap formed between the first heating portions 51 of the heater 5 increases. Therefore, the CO gas can be directly exhausted from the gap of the first heating unit 51, which has the highest temperature and the amount of CO gas generated, in the shortest path, so that the carbon concentration in the silicon single crystal 10 can be reduced more reliably. can do.

[3] Actions and Effects of the Embodiment In such an exhaust flow path, the inert gas introduced from the gas introduction port 13 (see FIG. 1) at the upper part of the quartz crucible 3A is silicon as shown in FIG. It diffuses to the outside of the quartz crucible 3A along the melt surface of the melt 9. A part of the SiO gas on the surface of the silicon melt 9 flows along the back surface of the heater 5, and a part of the other gas flows between the quartz crucible 3A and the heater 5. At this time, the gas flowing between the quartz crucible 3A and the heater 5 passes through the inside of the heater 5 and reacts with the carbon material constituting the heater 5 to generate CO gas.
The generated CO gas is sucked from the central exhaust port 16A formed on the back surface of the heater 5, flows through the exhaust duct 15, and is discharged from the exhaust port 14 without diffusing to other parts.

Therefore, the CO gas generated by the reaction of the SiO gas with carbon is sucked in from the central exhaust port 16A and exhausted from the exhaust port 14 through the exhaust duct 15, so that the CO gas can be directly exhausted in the shortest route. The carbon concentration in the silicon single crystal 10 pulled up by the apparatus 1 can be reduced.
Further, since the CO gas can be exhausted from the slits between the plurality of first heating portions 51 arranged in the width direction of the heater 5, the CO gas can be exhausted in the shortest path from the CO gas generation position, and the silicon single crystal 10 can be exhausted. Carbon concentration can be reduced.

By arranging the plurality of exhaust ducts 15 at equal positions around the heater 5, CO gas can be exhausted from even positions around the quartz crucible 3A. Therefore, since the amount of carbon incorporated into the silicon single crystal 10 can be made uniform around the crystal axis of the silicon single crystal 10, the carbon concentration of the silicon single crystal can be made uniform. Further, since each exhaust duct 15 is provided with the central exhaust port 16A, efficient exhaust can be performed, and the carbon concentration in the silicon single crystal 10 can be further reduced.

[4] Second Embodiment Next, a second embodiment of the present invention will be described. In the following description, the same parts as those already described will be designated by the same reference numerals and the description thereof will be omitted.
In the first embodiment described above, the central exhaust port 16A is formed at a substantially central portion on the back surface of the one-stage heater 5, and the generated CO gas is exhausted.

On the other hand, in the present embodiment, as shown in FIG. 5, two-stage heaters 5A and 5B are used, and a central exhaust port 16A is formed in the center of the back surface of the upper heater 5A, and the lower part is below. The difference is that the central exhaust port 16B is formed in the central portion of the back surface of the heater 5B, and CO gas is exhausted from the central exhaust ports 16A and 16B, respectively. The number of stages of the heater is not limited to this, and when heaters having two or more stages are arranged, a central exhaust port may be formed in the central portion of the back surface of each heater.
With this embodiment as well, it is possible to enjoy the same actions and effects as those of the first embodiment described above.

[5] Modifications of the Embodiment The present invention is not limited to the embodiments described above, but also includes modifications as shown below.
In the above-described embodiment, the inner cylinder 16 to which the exhaust duct 15 is attached is formed with only one central exhaust port 16A, but the present invention is not limited to this. That is, in addition to the central exhaust port 16A, an upper exhaust port for taking in CO gas may be formed in the upper part of the heater 5, or a lower exhaust port for taking in CO gas may be formed in the lower part of the heater 5.

In the above-described embodiment, the heater 5 meanders in the width direction of the heater 5, but the present invention is not limited to this. That is, the heater may meander in the vertical direction. In short, the shape does not matter as long as there is a slit-shaped gap between the heating bodies constituting the heater.
In addition, the specific structure, shape, and the like when carrying out the present invention may be other structures and the like as long as the object of the present invention can be achieved.

Next, examples of the present invention will be described. The present invention is not limited to the following examples.
[1] Actual Reactor Test Using the operating lifting device 1 shown in FIG. 1, an exhaust duct 15 is formed on the back surface of the heater 5, and the central exhaust port 16A is located at a position approximately half of the height direction of the heater 5. The carbon concentration in the raised silicon single crystal 10 was measured in the case where the heater 5 was formed (Example) and the case where the lower exhaust port was formed below the lower end in the height direction of the heater 5 (Comparative Example). .. The results are shown in FIG. The inner cylinder 16 and the exhaust duct 15 on which the central exhaust port 16A is formed are made of a carbon material such as a graphite material or a carbon fiber reinforced composite material.

As can be seen from FIG. 6, when comparing the examples and the comparative examples, the comparative examples tend to have a higher carbon concentration than the carbon concentration of the examples from the beginning of pulling up the silicon single crystal 10. Further, it was confirmed that in the comparative example, the solidification rate became higher, that is, as the silicon single crystal 10 was pulled up, the carbon concentration became higher than that in the example.
On the other hand, in the examples, it was confirmed that the carbon concentration in the silicon single crystal 10 was suppressed to be lower than that in the case of the lower exhaust, and the CO gas exhaust efficiency by the central exhaust port 16A was good.

[2] Confirmation by simulation Next, using numerical simulation software, the carbon concentration in the silicon melt 9 for each exhaust position was estimated.
Specifically, as shown in FIG. 7, the silicon melt 9 is used for the lower exhaust only (A), the intermediate exhaust only (B), the intermediate exhaust and the lower exhaust (C), and the intermediate exhaust and the upper exhaust (D). The carbon concentration inside was estimated. The results are shown in FIG.
In the actual raising, carbon is taken into the silicon single crystal 10 according to segregation with the carbon concentration in the silicon melt 9 as the initial concentration, so the calculated value by the simulation corresponds to the carbon concentration of the actual silicon single crystal 10. You can think of it as.

Similar to the actual furnace test, in the case of only the lower exhaust (A), as shown in FIG. 8, the carbon concentration in the silicon melt 9 is the highest. In the case of only the intermediate exhaust (B), it was confirmed that the carbon concentration in the silicon melt 9 was the lowest.
In the case of the intermediate exhaust and the lower exhaust (C), it was confirmed that the carbon concentration in the silicon melt 9 was lower than that in the case of the lower exhaust (A), though not as much as the intermediate exhaust only (B). Was done.

Similarly, with respect to the intermediate exhaust gas and the upper exhaust gas (D), it was confirmed that the carbon concentration in the silicon melt 9 was lower than that of the lower exhaust gas only (A).
From the above, it was found that the carbon concentration in the silicon single crystal 10 can be reduced by combining the upper exhaust with the intermediate exhaust and the lower exhaust with the intermediate exhaust.
When the upper exhaust or the lower exhaust is combined with the intermediate exhaust, the carbon concentration in the silicon single crystal 10 can be lowered only by the intermediate exhaust because the upper exhaust and the lower exhaust are present. It is presumed that this is because the exhaust efficiency of the exhaust is reduced.

1 ... Pulling device, 2 ... Chamber, 3 ... Crucible, 3A ... Quartz crucible, 3B ... Graphite crucible, 4 ... Support shaft, 5, 5A, 5B ... Heater, 6 ... Insulation material, 7 ... Pulling shaft, 8 ... Seed crystal , 9 ... Silicon melt, 10 ... Silicon single crystal, 12 ... Heat shield, 13 ... Gas inlet, 14 ... Exhaust port, 15 ... Exhaust duct, 16 ... Inner cylinder, 16A, 16B ... Central exhaust port, 51 ... First heating unit, 52, 53 ... Second heating unit, H0, H1, H2 ... Range in the height direction.

Claims (9)

Manufacture of a silicon single crystal for producing a silicon single crystal using a chamber, a quartz crucible provided in the chamber, and a pulling device provided so as to surround the quartz crucible and having a heater for heating the quartz crucible. It ’s a method,
A method for producing a silicon single crystal, which comprises exhausting the gas introduced into the pulling device during pulling only from an exhaust port formed at a position overlapping at least a part of the back surface of the heater. In the method for producing a silicon single crystal according to claim 1,
Each of the heaters extends in the vertical direction and is arranged with a gap in the width direction orthogonal to the vertical direction. It is provided with a second heating part that alternately connects the lower ends of the above, and is formed in a serpentine shape.
A method for producing a silicon single crystal, wherein an exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping with at least a part of the back surface of the first heating portion. In the method for producing a silicon single crystal according to claim 2.
An exhaust port for exhausting air from the back surface of the heater is formed between a second heating portion that connects the upper ends of the first heating portion and a second heating portion that connects the lower ends of the first heating portion. A method for producing a silicon single crystal, which is characterized by being present. In the method for producing a silicon single crystal according to claim 3,
A method for producing a silicon single crystal, wherein an exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping the back surface of the first heating unit. With the chamber
A quartz crucible provided in the chamber and
A heater arranged so as to surround the quartz crucible and heating the quartz crucible,
Silicon characterized by comprising an exhaust flow path for exhausting gas introduced into the chamber during pulling only from an exhaust port formed at a position overlapping at least a part of the back surface of the heater. Single crystal pulling device. In the silicon single crystal pulling device according to claim 5.
Each of the heaters extends in the vertical direction and is arranged with a gap in the width direction orthogonal to the vertical direction. It is provided with a second heating part that alternately connects the lower ends of the above, and is formed in a serpentine shape.
A silicon single crystal pulling device characterized in that an exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping with at least a part of the back surface of the first heating portion. In the silicon single crystal pulling device according to claim 6.
An exhaust port for exhausting air from the back surface of the heater is formed between a second heating portion that connects the upper ends of the first heating portion and a second heating portion that connects the lower ends of the first heating portion. A silicon single crystal pulling device characterized by being present. In the silicon single crystal pulling device according to claim 7.
A silicon single crystal pulling device characterized in that an exhaust port for exhausting air from the back surface of the heater is formed at a position overlapping the back surface of the first heating unit. In the silicon single crystal pulling device according to any one of claims 5 to 8.
A silicon single crystal pulling device provided above the quartz crucible and provided with a heat shield for shielding heat from the silicon melt in the quartz crucible.

Images