Single crystal manufacturing device

Abstract

The present invention is a single crystal manufacturing apparatus for growing a single crystal by the Czochralski method, comprising: a main chamber housing a crucible for receiving a molten raw material and a heater for heating the molten raw material; a lifting chamber extending above the main chamber and receiving a grown single crystal; and a cooling vessel extending from at least the ceiling portion of the main chamber toward the surface of the molten raw material to surround the single crystal being lifted and forcibly cooled by a cooling medium. The apparatus is characterized by having a first cooling auxiliary vessel fitted to the inside of the cooling vessel and a second cooling auxiliary vessel screw-coupled from the bottom side to the outside of the first cooling auxiliary vessel, and the gap between the bottom surface of the cooling vessel and the top surface of the second cooling auxiliary vessel is 0 mm or more and 1.0 mm or less. Accordingly, the apparatus can provide a single crystal manufacturing apparatus capable of increasing the growth rate of the single crystal by efficiently cooling the single crystal being grown.

Description

Technology Field

[0001] The present invention relates to an apparatus for manufacturing single crystals, such as silicon single crystals, by the Czochralski method. Background Technology

[0002] Semiconductor substrates such as silicon or gallium arsenide are composed of single crystals and are used in computer memory ranging from small to large sizes, and there is a demand for increased capacity, lower costs, and higher quality of memory devices.

[0003] Conventionally, as one of the single crystal manufacturing methods for manufacturing single crystals that satisfy the requirements of these semiconductor substrates, the Czochralski method (CZ method) is known, in which a seed crystal is immersed in a molten semiconductor raw material contained in a crucible and then pulled to produce a large-diameter, high-quality single crystal.

[0004] Hereinafter, a conventional single crystal manufacturing apparatus by the CZ method will be explained with reference to Fig. 4, using the growth of a silicon single crystal as an example.

[0005] A single crystal manufacturing apparatus (conventional example) (400) used when growing a single crystal by the CZ method generally has a quartz crucible (3) that can be raised and lowered and contains a raw material molten liquid (5), a graphite crucible (4) that supports the quartz crucible (3), a heater (2) arranged to surround the crucibles (3 and 4), and an insulating material (18) arranged to surround the heater (2) arranged in a main chamber (1) for growing a single crystal (hereinafter simply referred to as a crystal) (6), and a lifting chamber (7) for receiving and extracting the grown single crystal (6) is connected at the top of the main chamber (1).

[0006] The single crystal manufacturing device (400) may additionally include a gas inlet (11), a gas outlet (12), a cooling tank (13), a cooling auxiliary tank (14), and a heat shielding member (17).

[0007] When manufacturing a single crystal (6) using such a single crystal manufacturing device (400), a seed crystal (8) is immersed in the raw material melt (5), and while rotating it, it is gently raised upward to grow a rod-shaped single crystal (6). At the same time, the crucibles (3 and 4) are raised in accordance with the growth of the crystal so that the height of the melt surface is always maintained constant to obtain the desired diameter and crystal quality.

[0008] And, when growing a single crystal (6), the seed crystal (8) mounted on the seed holder (9) is immersed in the molten raw material, and then the wire (10) is gently wound up while rotating the seed crystal (8) in the desired direction by means of a lifting mechanism (not shown), thereby growing the single crystal (6) at the tip of the seed crystal (8).

[0009] In the manufacture of a single crystal (6) by the CZ method described above, the grown-in defect formed in the single crystal can be controlled by the ratio of the temperature gradient within the crystal to the growth rate (growth rate) of the single crystal, and by controlling this, it is possible to grow a defect-free single crystal (6) (Patent Document 1).

[0010] Therefore, in manufacturing a defect-free crystal, and in increasing productivity by accelerating the growth rate of the single crystal (6), it is important to increase the cooling effect of the single crystal (6) being grown. Prior art literature

[0011] Japanese Patent Publication No. H11-157996, Japanese Patent Publication No. 2009-161416, Japanese Patent Publication No. 2020-152612, Japanese Patent Publication No. 2014-43386, Japanese Patent No. 6825728 Specification The problem to be solved

[0012] Accordingly, as a method for efficiently cooling a single crystal, a cooling auxiliary container made of a material such as graphite, having axial slits, is fitted into a water-cooled cooling container placed around the crystal and stretched toward the surface of the molten liquid (Patent Document 2). However, in this method, there is a problem in that the adhesion between the water-cooled cooling container and the cooling auxiliary container is poor, making it difficult to efficiently dissipate heat from the crystal.

[0013] Accordingly, Patent Document 3 proposes a method of bringing the cooling tank and the cooling auxiliary tank into close contact by pressing a diameter-enlarging member into a cooling auxiliary tank having an axial slit. By increasing the contact of the cooling auxiliary tank, it became possible to improve heat transfer from the cooling auxiliary tank to the cooling tank and to improve the crystal lifting speed.

[0014] In addition, Figure 2 of Patent Document 4 discloses an HZ structure in which the inner surface of a cooling tank is in close contact with a cooling auxiliary tank, and the bottom surface of the cooling tank facing the molten liquid surface is covered with a heat-insulating member.

[0015] Furthermore, Patent Document 5 proposes a structure for further accelerating the crystal growth rate by covering the bottom surface of the cooling tank facing the molten raw material with a flange protruding from the inside to the outside of the cooling auxiliary tank, thereby lowering the temperature of the cooling auxiliary tank and efficiently cooling the crystal being pulled. However, in this method, since the distance and tightness between the bottom surface of the cooling tank and the cooling auxiliary tank flange are determined by dimensional tolerances, there is a problem in that it is difficult to achieve a stable high-speed crystal growth rate. In some cases, the cooling tank and the flange are tightly fitted together, and damage occurs due to thermal expansion during operation, making it difficult to continue operation. Accordingly, a measure is required to achieve a safe and stable high-speed crystal growth rate regardless of dimensional tolerances by appropriately controlling the distance between the bottom surface of the cooling tank and the upper surface of the cooling auxiliary tank flange while keeping the inner surface of the cooling tank and the outer surface of the cooling auxiliary tank in close contact.

[0016] The present invention was made to solve the above problem and aims to provide a single crystal manufacturing apparatus capable of accelerating the growth rate of a single crystal by efficiently cooling the single crystal being grown. means of solving the problem

[0017] To solve the above problem, the present invention provides a single crystal manufacturing apparatus for growing a single crystal by the Czochralski method, comprising: a main chamber housing a crucible for receiving a raw material molten liquid and a heater for heating the raw material molten liquid; a lifting chamber extending above the main chamber and receiving a grown single crystal that is lifted; and a cooling vessel extending from at least the ceiling portion of the main chamber toward the surface of the raw material molten liquid to surround the single crystal being lifted and forcibly cooling it with a cooling medium.

[0018] A single crystal manufacturing apparatus is provided, characterized by having a first cooling auxiliary container fitted to the inner side of the cooling container, and a second cooling auxiliary container screw-coupled from the lower side to the outer side of the first cooling auxiliary container, and further having a gap between the bottom surface of the cooling container and the upper surface of the second cooling auxiliary container of 0 mm or more and 1.0 mm or less.

[0019] According to such a single crystal manufacturing apparatus, a second cooling auxiliary tank is screw-coupled from the bottom side to the outer side of a first cooling auxiliary tank, thereby making it possible to adjust the gap between the bottom surface of the cooling tank facing the surface of the molten raw material and the top surface of the second cooling auxiliary tank regardless of dimensional tolerance, and stably increase the crystal growth rate.

[0020] Furthermore, by making the gap between the bottom surface of the cooling tank and the top surface of the second cooling auxiliary tank 0 mm or more and 1.0 mm or less, heat from the single crystal being grown can be efficiently arranged, and the crystal growth rate can be accelerated.

[0021] The material of the first cooling auxiliary tank and the second cooling auxiliary tank is preferably one of graphite, carbon composite, stainless steel, molybdenum, and tungsten.

[0022] By using the first cooling auxiliary tank and the second cooling auxiliary tank made of such material, radiant heat from the crystal can be efficiently absorbed and the heat can be efficiently transferred to the cooling tank.

[0023] It is preferable that the bottom of the second cooling auxiliary tank is positioned lower toward the surface of the raw material than the bottom of the first cooling auxiliary tank.

[0024] By doing so, a more significant acceleration of the crystal growth rate is achieved.

[0025] The material of the first cooling auxiliary tank and the second cooling auxiliary tank is graphite, and

[0026] The above single crystal manufacturing apparatus preferably further comprises a diameter-enlarging member fitted to the inner side of the first cooling auxiliary container to bring the first cooling auxiliary container and the cooling container into close contact.

[0027] Since graphite material has a thermal conductivity equal to or greater than that of metal and also has a higher emissivity than metal, if the first cooling auxiliary tank and the second cooling auxiliary tank made of graphite material are used, radiant heat from the crystal can be absorbed more efficiently and the heat can be transferred more efficiently to the cooling tank.

[0028] In addition, by fitting a diameter-enlarging member to the inner side of the first cooling auxiliary container so as to bring the first cooling auxiliary container and the cooling container into close contact, it is possible to improve heat transfer from the first cooling auxiliary container to the cooling container and further improve the crystal lifting speed. Effects of the invention

[0029] As described above, the single crystal manufacturing apparatus of the present invention has a forced-cooled cooling tank and a first cooling auxiliary tank fitted to the inside of the cooling tank, and a second cooling auxiliary tank is screw-coupled from the bottom side to the outside of the first cooling auxiliary tank, and by making the gap between the bottom surface of the cooling tank facing the surface of the raw material molten liquid and the top surface of the second cooling auxiliary tank 0 mm or more and 1.0 mm or less, it is possible to efficiently arrange heat from the single crystal being grown and to accelerate the growth rate of the single crystal. Brief explanation of the drawing

[0030] FIG. 1 is a schematic cross-sectional view showing an example of a single crystal manufacturing apparatus of the present invention. FIG. 2 is a schematic cross-sectional view showing another example of a single crystal manufacturing apparatus of the present invention. FIG. 3 is a schematic cross-sectional view showing the single crystal manufacturing apparatus used in Comparative Example 1. FIG. 4 is a schematic cross-sectional view showing an example of a general single crystal manufacturing apparatus. FIG. 5 is a graph showing the gap between the bottom surface of the cooling tank in Example 1 and Comparative Example 1 and the top surface of the second cooling auxiliary tank (the top surface of the flange portion of the first cooling auxiliary tank). Figure 6 is a graph showing the crystal growth rate of defect-free crystals obtained in Example 1 and Comparative Example 1. Figure 7 is a graph showing the relationship between the gap between the bottom surface of the cooling tank and the top surface of the second cooling auxiliary tank and the crystal growth rate obtained in Example 3 and Comparative Example 2. Specific details for implementing the invention

[0031] As described above, in the manufacture of single crystals by the CZ method, accelerating the growth rate of the single crystal is a major means to improve productivity and reduce costs. It is known that in order to accelerate the growth rate of the single crystal, radiant heat from the single crystal must be efficiently removed and the temperature gradient of the crystal increased.

[0032] A large-scale operation was carried out.

[0033] As shown in Patent Document 5, the closer the distance between the bottom surface of the cooling tank and the cooling auxiliary tank, the faster the crystal growth rate becomes. However, since the distance between the two is determined by the tolerance of the cooling tank and the cooling auxiliary tank, there is a difficult challenge in stably increasing the crystal growth rate. When the distance between the cooling tank and the cooling auxiliary tank flange is extremely small, they fit together tightly, and there are cases where they break during operation, making it impossible to continue operation. To stably increase the crystal growth rate, it is important to appropriately control the distance between the bottom surface of the cooling tank and the cooling auxiliary tank.

[0034] The inventors, having repeatedly examined the above problem, have completed the present invention by positing that a single crystal manufacturing apparatus for growing a single crystal by the Czochralski method comprises a main chamber containing a crucible for receiving a raw material molten liquid and a heater for heating the raw material molten liquid, a lifting chamber extending above the main chamber and receiving a grown single crystal, and a cooling vessel extending from at least the ceiling portion of the main chamber toward the surface of the raw material molten liquid to surround the single crystal being lifted and forcibly cooling it with a cooling medium, wherein the apparatus is characterized by having a first cooling auxiliary vessel fitted inside the cooling vessel and a second cooling auxiliary vessel screw-coupled from the lower end to the outside of the first cooling auxiliary vessel, thereby appropriately controlling the distance between the cooling vessel and the cooling auxiliary vessel to efficiently cool the cooling auxiliary vessel and efficiently arrange the radiant heat from the single crystal, so as to achieve a significantly high growth rate of the single crystal.

[0035] That is, the present invention is a single crystal manufacturing apparatus for growing a single crystal by the Czochralski method, comprising: a main chamber containing a crucible for receiving a raw material molten liquid and a heater for heating said raw material molten liquid; a lifting chamber extending above said main chamber and receiving a grown single crystal that is lifted; and a cooling vessel extending from at least the ceiling portion of said main chamber toward the surface of the raw material molten liquid to surround said single crystal being lifted and forcibly cooled by a cooling medium.

[0036] A single crystal manufacturing apparatus is characterized by having a first cooling auxiliary container fitted to the inner side of the cooling container, and a second cooling auxiliary container screw-coupled from the lower side to the outer side of the first cooling auxiliary container, and further having a gap between the bottom surface of the cooling container and the upper surface of the second cooling auxiliary container of 0 mm or more and 1.0 mm or less.

[0037] Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to FIG. 1, but the present invention is not limited thereto. Meanwhile, descriptions of the same as the conventional device shown in FIG. 4 may be appropriately omitted.

[0038] The single crystal manufacturing apparatus (100) of the present invention shown in FIG. 1 comprises a main chamber (1) that houses a quartz crucible (3) and a graphite crucible (4) for receiving a raw material molten liquid (5), and a heater (2) for heating the raw material molten liquid (5); a lifting chamber (7) that is extended above the main chamber (1) and receives a grown single crystal (6) that is lifted; a cooling tank (13) that is extended from at least the ceiling portion of the main chamber (1) toward the surface (5a) of the raw material molten liquid to surround the single crystal (6) being lifted and is forcibly cooled by a cooling medium; a first cooling auxiliary tank (14) fitted inside the cooling tank (13); and a second cooling auxiliary tank (15) that is screw-coupled from the bottom (14b) side to the outside of the first cooling auxiliary tank (14).

[0039] In the single crystal manufacturing apparatus (100), the gap between the bottom surface (13a) of the cooling tank (13) facing the molten raw material (5) and the top surface (15a) of the second cooling tank (15) can be adjusted by screwing the second cooling tank (15) from the bottom side to the outside of the first cooling tank (14). More specifically, the second cooling tank (15) is screwed from the bottom (14b) side of the portion (14a) that is extended toward the surface (5a) of the molten raw material among the first cooling tank (14) fitted inside the cooling tank (13). Accordingly, as shown in FIG. 1, the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling tank (15) face each other. With the second cooling auxiliary tank (15) screw-coupled to the outer side of the first cooling auxiliary tank (14) from the lower side (14b), the gap between the bottom surface (13a) of the cooling tank (13) and the upper surface (15a) of the second cooling auxiliary tank (15) can be stably and easily adjusted regardless of dimensional tolerance by tightening the second cooling auxiliary tank (15) upward or lowering the second cooling auxiliary tank (15) downward.

[0040] In the present invention, the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) is set to be 0 mm or more and 1.0 mm or less. If the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) exceeds 1.0 mm, the first cooling auxiliary tank and the second cooling auxiliary tank are not sufficiently cooled to a low temperature, and the high speed of the single crystal growth rate cannot be achieved. If the gap is 1.0 mm or less, the significant high speed of the single crystal growth rate can be achieved. As shown in FIG. 1, when the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) is 0 mm, the two come into contact and adhere closely, and the crystal growth rate becomes maximum.

[0041] Furthermore, in order to efficiently absorb radiant heat from the crystal and efficiently transfer the heat to the cooling tank, the materials of the first cooling auxiliary tank (14) and the second cooling auxiliary tank (15) in the present invention are preferably one or more of graphite, carbon composite, stainless steel, molybdenum, and tungsten. Among the above materials, graphite is particularly preferred, as its thermal conductivity is equal to or greater than that of metal and its emissivity is higher than that of metal.

[0042] The lower end (15b) of the second cooling auxiliary tank (15) is preferably positioned downward toward the surface (5a) of the raw material molten liquid than the lower end (14b) of the first cooling auxiliary tank (14), as in the single crystal manufacturing apparatus (200) of the example shown in FIG. 2. By doing so, the second cooling auxiliary tank (15), which is cooled by the cooling tank (13), faces the single crystal (6) being raised, allowing heat from the crystal to be efficiently distributed and a significant increase in the crystal growth rate is achieved.

[0043] The single crystal manufacturing apparatus (100 and 200) of FIGS. 1 and 2 further includes a diameter-enlarging member (16) fitted inside the first cooling auxiliary tank (14). By fitting the diameter-enlarging member (16) to the first cooling auxiliary tank (14), the adhesion between the cooling tank (13) and the first cooling auxiliary tank (14) can be increased, and accordingly, it becomes possible to improve heat transfer from the first cooling auxiliary tank (14) to the cooling tank (13) and further improve the crystal lifting speed.

[0044] Examples

[0045] The present invention will be specifically described below using examples and comparative examples, but the present invention is not limited thereto.

[0046] (Example 1)

[0047] A single crystal was manufactured using four single crystal manufacturing devices (100) as shown in FIG. 1. The cooling tank (13) and the first cooling auxiliary tank (14) were brought into close contact by a diameter-enlarging member (16). The second cooling auxiliary tank (15) was screw-coupled from the bottom (14b) side to the outer side of the first cooling auxiliary tank (14). It was confirmed by actual measurement that the bottom surface (13a) of the cooling tank (13) facing the raw material melt (5) and the top surface (15a) of the second cooling auxiliary tank (15) were in close contact. That is, in Example 1, the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) was 0 mm. The second cooling auxiliary tank (15) was structured to cover the entire area of ​​the bottom surface (13a) of the cooling tank (13). The axial length of the second cooling auxiliary tank (15) is set to 70 mm, and the bottom (15b) of the second cooling auxiliary tank (15) is positioned 50 mm above the bottom (14b) of the first cooling auxiliary tank (14). The material of the first cooling auxiliary tank (14) and the second cooling auxiliary tank (15) is graphite, which has a thermal conductivity equal to or greater than that of metal and a radiation rate higher than that of metal.

[0048] A single crystal (6) was grown using this single crystal manufacturing device (100), and a growth rate was determined such that all of them were defect-free. Since the margin for the growth rate to obtain a defect-free crystal is very narrow, it is easy to determine an appropriate growth rate. The evaluation of whether the single crystal has defects was performed by cutting a sample from the manufactured single crystal and evaluating whether it became a defect-free region by selective etching.

[0049] (Example 2)

[0050] A single crystal was manufactured using four single crystal manufacturing devices (200) as shown in FIG. 2. A single crystal was manufactured using the same device and conditions as described in Example 1, except that the bottom of the second cooling auxiliary tank (15) was located 50 mm lower than the bottom (14b) of the first cooling auxiliary tank (14).

[0051] (Comparative Example 1)

[0052] A single crystal was manufactured using ten single crystal manufacturing devices (300) as shown in FIG. 3. The first cooling auxiliary tank (14) was shaped to have a flange (14c) that covers the bottom surface (13a) of the cooling tank (13) facing the raw material melt (5) by protruding from the inside to the outside of the cooling tank (13). At this time, the gap between the bottom surface (13a) of the cooling tank (13) facing the raw material melt (5) and the upper surface of the flange portion (14c) of the first cooling auxiliary tank (14) was designed to be 0.4 mm. Considering dimensional tolerances, a design that makes the gap narrower than this is not possible. In addition, the flange portion (14c) was shaped to cover the entire area of ​​the bottom surface (13a) of the cooling tank (13), and the thickness of the flange portion (14c) was set to 70 mm. The gap between the bottom surface (13a) of the cooling tank (13) and the upper surface of the flange portion (14c) of the first cooling auxiliary tank (14) was measured by actual measurement.

[0053] In addition, the single crystal manufacturing apparatus (300) did not have the second cooling auxiliary tank (15) shown in FIGS. 1 and 2. Other than that, the single crystal manufacturing was performed using the same apparatus and conditions as in Example 1.

[0054] (Example 3)

[0055] A single crystal was manufactured using a single crystal manufacturing apparatus (100) as shown in FIG. 1. The gap between the bottom surface (13a) of the cooling tank (13) facing the raw material melt (5) and the top surface (15a) of the second cooling auxiliary tank (15) was set to 0 to 1.0 mm by screw connection, and the crystal growth rate was determined. Other conditions were the same as those described in Example 1, and the single crystal was manufactured using the same apparatus and conditions.

[0056] (Comparative Example 2)

[0057] A single crystal was manufactured using a single crystal manufacturing apparatus (100) as shown in FIG. 1. The gap between the bottom surface (13a) of the cooling tank (13) facing the raw material melt (5) and the top surface (15a) of the second cooling auxiliary tank (15) was set to 1.1 to 1.4 mm by screw connection, and the crystal growth rate was determined. Other conditions were the same as those described in Example 1, and the single crystal was manufactured using the same apparatus and conditions.

[0058] FIG. 5 shows the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) measured in Example 1, and the gap between the bottom surface (13a) of the cooling tank (13) and the top surface of the flange portion (14c) of the first cooling auxiliary tank (14) measured in Comparative Example 1. In Example 1, the gap is 0mm in all operations, whereas in Comparative Example 1, the gap varies significantly from 0 to 1.0mm due to the dimensional tolerance of the cooling tank (13) and the first cooling auxiliary tank (14).

[0059] FIG. 6 shows the crystal growth rate of defect-free crystals obtained in Example 1 and Comparative Example 1. The crystal growth rates of Example 1 and Comparative Example 1 are each set as the average value of the entire operation, and are shown as relative values ​​when the average value of the crystal growth rate of Comparative Example 1 is normalized to 1. The crystal growth rate of Example 1 was accelerated by 3.7% compared to Comparative Example 1. In Comparative Example 1, due to the dimensional tolerance of the cooling tank (13) and the first cooling auxiliary tank (14) shown in FIG. 5, a gap between the bottom surface (13a) of the cooling tank (13) and the upper surface of the flange portion (14c) of the first cooling auxiliary tank (14) was deviated, and the average crystal growth rate was reduced, whereas in Example 1, a stable high crystal growth rate was obtained.

[0060] FIG. 7 shows the crystal growth rate when the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15), as performed in Example 3 and Comparative Example 2, is adjusted to between 0 and 1.4 mm by screw connection. The crystal growth rate in FIG. 7 is shown as a relative value when the crystal growth rate is standardized to 1 when the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) is 1.0 mm. When the gap is 0 mm, the crystal growth rate was maximum at 1.090. On the other hand, when the gap is 1.1 mm or more, the crystal growth rate significantly decreased to 0.965. When the gap is 1.1 mm or more, the distance between the bottom surface (13a) of the cooling tank (13) and the second cooling auxiliary tank (15) is large, so the first cooling auxiliary tank (14) and the second cooling auxiliary tank (15) are not sufficiently cooled down, and it can be seen that radiant heat from the single crystal is not efficiently removed. From the above, it can be seen that if the gap between the bottom surface (13a) of the cooling tank (13) and the top surface (15a) of the second cooling auxiliary tank (15) is 1.0 mm or less, a significant increase in the crystal growth rate can be realized.

[0061] The crystal growth rates obtained in Example 1, Example 2, and Comparative Example 1 are summarized in Table 1 below. The crystal growth rates in Table 1 are presented as relative values ​​when the average value of the crystal growth rate of Comparative Example 1 is normalized to 1. Example 1 showed a 3.7% increase in crystal growth rate compared to Comparative Example 1, and Example 2 showed an 8.0% increase compared to Comparative Example 1.

[0062] [Table 1]

[0063]

[0064] Meanwhile, the present invention is not limited to the above embodiments. The above embodiments are examples, and any configuration that is substantially identical to the technical concept described in the claims of the present invention and exhibits the same functional effects is included within the technical scope of the present invention.

Claims

Claim 1 A single crystal manufacturing apparatus for growing a single crystal by the Czochralski method, comprising: a main chamber housing a crucible for receiving a molten raw material and a heater for heating the molten raw material; a lifting chamber extending above the main chamber and receiving a grown single crystal; and a cooling vessel extending from at least the ceiling portion of the main chamber toward the surface of the molten raw material to surround the single crystal being lifted and forcibly cooled by a cooling medium, wherein the apparatus comprises a first cooling auxiliary vessel fitted to the inside of the cooling vessel and a second cooling auxiliary vessel screw-coupled from the bottom side to the outside of the first cooling auxiliary vessel, wherein the gap between the bottom surface of the cooling vessel and the top surface of the second cooling auxiliary vessel is 0 mm or more and 1.0 mm or less, and the material of the first cooling auxiliary vessel and the second cooling auxiliary vessel is graphite, and wherein the single crystal manufacturing apparatus comprises the first cooling auxiliary vessel to bring the first cooling auxiliary vessel and the cooling vessel into close contact. A single crystal manufacturing apparatus characterized by additionally having a diameter-enlarging member fitted to the inner side. Claim 2 A single crystal manufacturing apparatus according to claim 1, characterized in that the lower end of the second cooling aid tank is positioned lower toward the surface of the raw material melt than the lower end of the first cooling aid tank. Claim 3 delete Claim 4 delete Claim 5 delete

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