KR20220146808A - Apparatus for growing silicon single crystal ingot - Google Patents

Abstract

An embodiment provides a device for growing a silicon single crystal ingot, including: a chamber body; a crucible provided inside the chamber body; a heating member provided around the crucible; a heat shield provided on the upper part of the crucible; a support member provided at the lower part of the crucible to elevate the crucible; a heat insulating member disposed around the support member at the lower part of the crucible; and a crucible cooling line disposed in an intermediate region of the heat insulating member.

Description

Silicon single crystal ingot growth apparatus {APPARATUS FOR GROWING SILICON SINGLE CRYSTAL INGOT}

The embodiment relates to an apparatus for growing a silicon single crystal ingot, and more particularly, to an apparatus for growing a silicon single crystal ingot with low oxygen.

A typical silicon wafer includes a single crystal growth process for making a single crystal ingot, a cutting process for cutting a single crystal ingot to obtain a thin disk-shaped wafer, and damage due to mechanical processing remaining on the wafer due to the cutting. .

The silicon single crystal ingot growth apparatus includes a crucible in which the silicon melt is stored, and a support member for supporting and elevating the crucible, and the heating member and the crucible at the side of the crucible may be elevated.

In this case, the silicon single crystal ingot grown from the silicon melt may contain oxygen atoms, and it is necessary to maintain a low oxygen concentration in order not to cause defects in the wafer manufactured from the silicon single crystal ingot.

In addition, oxygen atoms in the silicon single crystal ingot are derived from oxygen atoms included in the silicon melt, and the oxygen atoms may be supplied from the crucible to the silicon melt. In particular, oxygen is intensively supplied to the silicon melt from the bottom surface of the quartz crucible heated to a high temperature, which may result in an increase in the oxygen concentration of the wafer to be manufactured.

Therefore, it is necessary to reduce the oxygen concentration supplied to the silicon melt from the quartz crucible.

The embodiment is intended to provide an apparatus for growing a silicon single crystal ingot that can implement a low oxygen concentration of a wafer manufactured from a silicon single crystal ingot.

Embodiments include a chamber body; a crucible provided inside the chamber body; a heating member provided around the crucible; a heat shield provided on an upper portion of the crucible; a support member provided at a lower portion of the crucible to elevate the crucible; a heat insulating member disposed to surround the support member at a lower portion of the crucible; and a crucible cooling line disposed in the middle region of the heat insulating member.

The apparatus for growing a silicon single crystal ingot may further include a chamber cooling line having a thickness in the chamber body and being provided to wrap around the crucible at least once in the interior of the chamber body.

One end of the crucible cooling line may be connected to the chamber cooling line, and cooling water may be at least partially filled in the crucible cooling line and the chamber cooling line.

The support member includes a support part in direct contact with the bottom surface of the crucible and a lifting shaft connected to the support part, a width of the support part is greater than a width of the lifting shaft, and the crucible cooling line faces each other with the lifting shaft interposed therebetween. The vessel may include a first crucible cooling line and a second crucible cooling line.

A first end of the first crucible cooling line is connected to the chamber cooling line in region 1-1, and a second end of the first crucible cooling line is connected to the chamber cooling line in region 1-2, and The 1-1 area and the 1-2 area may face each other with the lifting shaft interposed therebetween.

A first end of the second crucible cooling line is connected to the chamber cooling line in a region 2-1, and a second end of the second crucible cooling line is connected to the chamber cooling line in a region 2-2, and The 2-1 region and the 2-2 region may face each other with the lifting shaft interposed therebetween.

The region 1-1 and the region 2-1 may be adjacent to each other, and the region 1-2 and the region 2-2 may be adjacent to each other.

Cooling water may be supplied from the chamber cooling line to the first crucible cooling line through the 1-1 end, and the cooling water may be discharged from the first crucible cooling line to the chamber cooling line through the 1-2 end. .

Cooling water from the chamber cooling line may be supplied to the second crucible cooling line through a 2-2 end, and the cooling water may be discharged from the second crucible cooling line to the chamber cooling line through the 2-1 end. .

An area of a cross section through which the coolant flows in the crucible cooling line may be smaller than an area of a cross section through which the coolant flows in the chamber cooling line.

In the silicon single crystal ingot growth apparatus according to the embodiment, cooling water is supplied from the chamber cooling line to the crucible cooling line under the crucible to prevent heating of the lower region of the crucible, and in particular, oxygen atoms are eluted from the lower surface of the quartz crucible to form a silicon melt. By preventing the supply, oxygen atoms in the silicon single crystal ingot and the wafer to be grown are reduced, so that the quality of the wafer can be improved.

1 is a view showing an apparatus for growing a silicon single crystal ingot according to an embodiment;
Figure 2 is a cross-sectional view of the area 'A' of Figure 1,
Figure 3 is a view showing the chamber cooling line of Figure 1,
4 is a view illustrating a support member and a heat insulating member of FIG. 1 .
5a and 5b are views showing the temperature distribution change of the lower and side surfaces of the crucible,
6a and 6b are views showing the temperature distribution change in the silicon melt,
7A and 7B are diagrams illustrating changes in oxygen concentration according to a change in temperature distribution in a silicon melt.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings to help the understanding of the present invention, examples will be described in detail.

However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided in order to more completely explain the present invention to those of ordinary skill in the art.

Also, as used hereinafter, relational terms such as "first" and "second," "upper" and "lower", etc., shall not necessarily require or imply any physical or logical relationship or order between such entities or elements. In other words, it may be used only to distinguish one entity or element from another entity or element.

1 is a view showing an apparatus for growing a silicon single crystal ingot according to an embodiment, FIG. 2 is a cross-sectional view of region 'A' of FIG. 1, FIG. 3 is a view showing the chamber cooling line of FIG. 1, FIG. 4 is FIG. 1 is a view showing the support member and the heat insulating member. Hereinafter, an apparatus for growing a silicon single crystal ingot according to an embodiment will be described with reference to FIGS. 1 to 4 .

The silicon single crystal ingot growth apparatus 1000 according to the embodiment includes a chamber body 110 in which a space for growing a silicon single crystal ingot from a silicon melt is formed therein, and the silicon melt is accommodated therein. A crucible 120 for, a heating member 130 for heating the crucible 120, a crucible support member 150 for supporting the crucible 120, rotating and elevating it, and a heating member for a silicon single crystal ingot ( A heat shield 140 positioned on the upper portion of the crucible 120 to block the heat of 130 and a water cooling tube (not shown) provided on the upper portion of the chamber body 110 to cool the elevated high-temperature silicon single crystal ingot ), and an inert gas supply unit (not shown) for supplying an inert gas to the inner region of the chamber body 110, and a heat insulating member 200 disposed to surround the support member 150 in the lower portion of the crucible 120, and A crucible cooling line 160 disposed in the middle region of the heat insulating member 200 may be included.

The chamber body 110 provides a space in which predetermined processes for forming a silicon single crystal ingot from a silicon melt (Si melt) are performed.

The crucible 120 may be provided in the chamber body 110 to contain a silicon melt (Si melt). The crucible 120 may include a first crucible 121 that is in direct contact with the silicon melt, and a second crucible 122 that surrounds and supports the outer surface of the first crucible 121 . The first crucible 121 may be made of quartz, and the second crucible 122 may be made of graphite.

When the first crucible 121 made of quartz is heated to a high temperature, oxygen may be eluted from the first crucible 121 . The second crucible 122 may be divided into two or four in case the first crucible 121 is expanded by heat. For example, when the second crucible 122 is divided into two, a gap is formed between the two parts, and even if the first crucible 121 inside is expanded, the second crucible 122 may not be damaged.

A heat insulating material may be provided in the chamber body 110 to prevent the heat of the heating member 130 from being emitted. In this embodiment, only the heat shield 140 of the upper portion of the crucible 120 is shown, but insulating materials may be respectively disposed on the side and the lower portion of the crucible 120 .

The heating member 130 may melt polycrystalline silicon supplied in the crucible 120 to make a silicon melt (Si melt). can

A magnetic field generating unit (not shown) may be provided outside the chamber body 110 to apply a horizontal magnetic field to the crucible 120 .

A support member 150 may be disposed at the center of the bottom surface of the crucible 120 to support the crucible 120 and to lift or rotate it. The support member 150 may include a support part 151 in direct contact with the bottom surface of the crucible 120 and an elevation shaft 152 connected to the support part 151 . In this case, the width of the support 151 may be greater than the width 152 of the elevating shaft, and the width may be the width in the horizontal direction in FIG. 1 or the like.

A seed (not shown) suspended on a seed chuck (not shown) above the crucible 120 is immersed in a silicon melt (Si melt), and as the silicon melt is solidified from the seed, a silicon single crystal ingot is formed. can be grown

During the process of growing the silicon single crystal ingot, an inert gas, for example, argon (Ar) may be supplied to the inside of the chamber body 110 .

FIG. 2 shows area 'A' of FIG. 1 and FIG. 3 shows the chamber cooling line of FIG. 1 , showing the circulation of cooling water in the crucible cooling line 160 and the chamber cooling line 300 .

As shown in FIG. 3 , the chamber body 110 has a thickness, that is, it may have a thickness defined by the inner surface 110a and the outer surface 110b of the chamber body 110 . In addition, the chamber cooling line 300 provided to surround the circumference of the crucible at least once in the interior of the chamber body 110 may be provided.

Referring to FIG. 3 , the chamber cooling line 300 may include first to fourth chamber cooling lines 300a to 300d. The first chamber cooling line 300a may be provided in a lower region of the chamber body 300 , and a cooling water supply unit (coolant In) supplied with cooling water from the outside may be provided. The fourth chamber cooling line 300d is provided in the upper region of the chamber body 300 , and a cooling water discharge unit (coolant Out) for discharging cooling water to the outside may be provided.

A second chamber cooling line 300b and a third chamber cooling line 300c may be sequentially disposed in a direction from the first chamber cooling line 300a to the fourth chamber cooling line 300d. The number of the chamber cooling lines 300 is not limited to three, and for convenience of explanation in FIG. 3 , the first chamber cooling line to the fourth chamber cooling line 300a to 300d are shown separately from each other, but in reality They are connected to each other, so that the coolant supplied from the outside of the chamber body 110 evenly passes through the circumference of the chamber body 110 to prevent overheating of the inner crucible 120 .

In addition, although the cooling water supply unit (coolant In) is provided in the lower region of the chamber body 110 in FIG. 3 and the cooling water discharge unit (coolant Out) is provided in the upper region, the present invention is not limited thereto and may be provided in the opposite direction.

As shown in FIG. 2, in area 'A' of FIG. 1, a crucible cooling line 160 is provided between the heat insulating members 200. In this embodiment, the first crucible with the lifting shaft 152 interposed therebetween. A cooling line 161 and a second crucible cooling line 162 may be provided.

And, unlike shown in FIG. 2 , the first and second crucible cooling lines 161 and 162 and the heat insulating member 200 may be spaced apart from each other without directly contacting each other.

As shown in FIG. 2 , the first crucible cooling line 161 has a first end 161a connected to the chamber cooling line 300 in the 1-1 region, and the first crucible cooling line 161 is The second end 161b is connected to the chamber cooling line 300 in the region 1-2, and the region 1-1 and the region 1-2 are provided in regions facing each other with the lifting shaft 152 interposed therebetween. can be

In addition, the second crucible cooling line 162 has a first end 162a connected to the chamber cooling line 300 in the 2-1 region, and a second end 162b of the second crucible cooling line 162 is The region 2-2 may be connected to the chamber cooling line 300 , and the region 2-1 and the region 2-2 may be provided in regions facing each other with the lifting shaft 152 interposed therebetween.

Also, as illustrated in FIG. 2 , the 1-1 region and the 2-1 region may be adjacent to each other, and the 1-2 region and the 2-2 region may be adjacent to each other.

At least a portion of the inside of the chamber cooling line 300 and the crucible cooling line 160 may be filled with cooling water to circulate, and the circulation of the cooling water is illustrated by arrows in FIG. 2 .

In detail, the cooling water is supplied from the chamber cooling line 300 to the first crucible cooling line 161 through the 1-1 end 161a, and the cooling water is supplied to the first crucible through the 1-2 end 161b. It may be discharged from the cooling line 161 to the chamber cooling line 300 .

In addition, the cooling water is supplied from the chamber cooling line 300 to the second crucible cooling line 162 through the 2-2 end 162b, and the cooling water is supplied to the second crucible cooling line through the 2-1 end 162a. from 162 to the chamber cooling line 300 .

In addition, the area Wb of the cross section through which the coolant flows in the crucible cooling line 160 may be larger than the area Wa of the cross section through which the coolant flows in the chamber cooling line 300 . Due to the difference in cross-sectional area, the flow of cooling water in the crucible cooling line 160 is relatively fast, so that the cooling effect of the lower part of the crucible 120 can be increased.

In FIG. 4 , an embodiment of the structure of the support member 150 and the heat insulating member 200 of FIG. 1 is shown in detail.

The crucible cooling line 160 is disposed between the heat insulating members 200 . That is, in the lower portion of the crucible cooling line 160 , the first portion 210 and the second portion 220 of the heat insulating member are interlocked with each other and disposed to stably support the crucible cooling line 160 . In addition, the third portion 230 of the heat insulating member is disposed above the crucible cooling line 160 to cover the crucible cooling line 160 .

This structure stably supports the crucible cooling line 160 , and the lifting shaft 152 may be raised or lowered in the central region of the first to third parts 210 to 230 of the heat insulating member 200 .

5A and 5B are diagrams illustrating a change in temperature distribution of a lower portion and a side surface of a crucible. Case 1 (Comparative Example) is a case in which a crucible cooling line is not provided, and Case 2 (Example) is a case in which a crucible cooling line is provided and the lower part of the crucible is cooled by cooling water.

In the case of the example, it can be seen that the lower temperature of the crucible is lower than that of the comparative example.

6a and 6b are diagrams showing the temperature distribution change in the silicon melt. In the case of the example compared to the comparative example, it can be seen that the temperature in the silicon melt is lowered particularly at the lower surface of the crucible.

7A and 7B are diagrams illustrating changes in oxygen concentration according to a change in temperature distribution in a silicon melt. It can be seen that in the case of the example compared to the comparative example, the oxygen concentration (in ppma) in the silicon melt is particularly small at the lower surface of the crucible.

In the above-described silicon single crystal ingot growth apparatus, cooling water is supplied from the chamber cooling line to the crucible cooling line at the bottom of the crucible to prevent heating of the lower region of the crucible, and in particular, oxygen atoms are eluted from the lower surface of the quartz crucible and supplied as a silicon melt. it can be prevented In addition, the crucible cooling line may be stably disposed inside the heat insulating member.

Accordingly, oxygen atoms supplied to the silicon melt are reduced, and oxygen atoms in the grown silicon single crystal ingot and wafer are reduced, so that the quality of the wafer can be improved.

As described above, although the embodiment has been described with reference to the limited embodiment and the drawings, the present invention is not limited to the above embodiment, and those skilled in the art to which the present invention pertains various modifications and variations from these descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the following claims as well as the claims and equivalents.

110: chamber body 120: crucible
121: first crucible 122: second crucible
130: heating member 140: heat shield
150: support member 151: support portion
152: lifting shaft 160: crucible cooling line
161, 162: first and second crucible cooling lines
161a, 162a: first end 162b, 162b: second end
200: heat insulating member 210 to 230: first to third parts
300: chamber cooling line 300a to 300d: first to third chamber cooling line
1000: growth device for silicon single crystal ingot

Claims (10)

chamber body;
a crucible provided inside the chamber body;
a heating member provided around the crucible;
a heat shield provided on an upper portion of the crucible;
a support member provided at a lower portion of the crucible to elevate the crucible;
a heat insulating member disposed to surround the support member at a lower portion of the crucible; and
An apparatus for growing a silicon single crystal ingot including a crucible cooling line disposed in an intermediate region of the heat insulating member. The method of claim 1,
The chamber body has a thickness, the silicon single crystal ingot growth apparatus further comprising a chamber cooling line provided to wrap around the crucible at least once in the interior of the chamber body. 3. The method of claim 2,
One end of the crucible cooling line is connected to the chamber cooling line, and cooling water is at least partially filled in the crucible cooling line and the chamber cooling line. The method of claim 1,
The support member includes a support portion in direct contact with the bottom surface of the crucible and a lifting shaft connected to the support portion,
The width of the support portion is greater than the width of the lifting shaft,
The crucible cooling line is an apparatus for growing a silicon single crystal ingot including a first crucible cooling line and a second crucible cooling line facing each other with the lifting shaft interposed therebetween. 5. The method of claim 4,
A first end of the first crucible cooling line is connected to the chamber cooling line in region 1-1, and a second end of the first crucible cooling line is connected to the chamber cooling line in region 1-2, The 1-1 region and the 1-2 region are the silicon single crystal ingot growing apparatus facing each other with the elevating axis interposed therebetween. 6. The method of claim 5,
A first end of the second crucible cooling line is connected to the chamber cooling line in region 2-1, and a second end of the second crucible cooling line is connected to the chamber cooling line in region 2-2, The 2-1 region and the 2-2 region are the silicon single crystal ingot growing apparatus facing each other with the elevating axis interposed therebetween. 7. The method of claim 6,
The 1-1 region and the 2-1 region are adjacent to each other, and the 1-2 region and the 2-2 region are adjacent to each other. 8. The method of claim 7,
The silicon cooling water is supplied from the chamber cooling line to the first crucible cooling line through the 1-1 end, and the cooling water is discharged from the first crucible cooling line to the chamber cooling line through the 1-2 end. Single crystal ingot growth apparatus. 9. The method of claim 8,
The silicon cooling water is supplied from the chamber cooling line to the second crucible cooling line through the 2-2 end, and the cooling water is discharged from the second crucible cooling line to the chamber cooling line through the 2-1 end. Single crystal ingot growth apparatus. 4. The method of claim 3,
The area of the cross section through which the coolant flows in the crucible cooling line is smaller than the area of the cross section through which the coolant flows in the chamber cooling line.

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