WO2014189160A1

WO2014189160A1 - Polysilicon manufacturing apparatus using single crystal silicon button

Info

Publication number: WO2014189160A1
Application number: PCT/KR2013/004524
Authority: WO
Inventors: 이진석; 안영수; 장보윤; 김준수
Original assignee: 한국에너지기술연구원
Priority date: 2013-05-23
Filing date: 2013-05-23
Publication date: 2014-11-27

Abstract

The present invention relates to a polysilicon manufacturing apparatus using a single crystal silicon button, comprising: a vacuum chamber for maintaining a vacuum atmosphere; an electron beam irradiation part, equipped in the vacuum chamber, for irradiating an electron beam; a silicon melting part, which is arranged in a region where the electron beam is irradiated by the electron beam irradiation part, and into which silicon raw materials, in the form of particles, are inserted, such that the silicon materials are melted by the electron beam, thereby producing a silicon melt; a unidirectional coagulation part having a cooling channel in the lower part thereof so as to coagulate the silicon melt supplied from the silicon melting part; and a start block, wherein the start block comprises: a single crystal silicon button which is manufactured separately and equipped inside the unidirectional coagulation part so as to transport the silicon melt supplied from the silicon melting part to the lower part of the unidirectional coagulation part; and a graphite dummy bar which is bonded to the lower surface of the single crystal silicon button so as to enable the single crystal silicon button to move.

Description

Polysilicon Manufacturing Equipment Using Single Crystal Silicon Button

The present invention relates to an apparatus for producing polysilicon through unidirectional solidification, wherein a start block used for unidirectional solidification is formed by using a single crystal silicon button to prevent contamination of the solidified silicon melt. It is about.

In general, in the case of silicon used as a wafer for semiconductors or solar cells, a carbon reducing agent such as silica (SiO 2) and coke in a natural state is obtained by a thermal carbon reduction method of reacting at high temperature using an arc or the like. . However, since the silicon obtained at this time contains a large amount of impurities and has a purity of about 99%, the semiconductor wafer (purity of 99.99999999% (10N) or higher) or the solar cell wafer (purity of 99.9999% (6N) must be further refined. It becomes more than)).

The purity of silicon is usually expressed as 2N, 3N, 6N, 11N or the like. In this case, the number before 'N' means the number of 9, the purity of 99% for 2N, 99.9999% for 6N, and 99.999999999% for 11N.

In the case of semiconductor grade silicon requiring ultra high purity, the purity reaches 11N. However, silicon used as a raw material of the photovoltaic cell is known to obtain a light conversion efficiency similar to that of applying 11N silicon even at a purity of 5N to 7N, which is relatively lower than that of semiconductor grade silicon 11N.

Semiconductor grade silicon is manufactured through a chemical gasification process. However, the silicon manufacturing process is known to generate a large amount of contaminants, low production efficiency, and high production cost.

Accordingly, the silicon used as a raw material of the solar cell is difficult to apply the semiconductor-grade silicon manufacturing process, and the metallurgical refining process that can mass-produce high purity silicon at low manufacturing cost has been actively developed.

Metallurgical refining of high-purity silicon for photovoltaic power generation has been developed such as vacuum refining, wet refining, oxidation, unidirectional solidification refining, and some of them are commercially available.

Among these metallurgical refining methods, silicon manufacturing technology by metal melting method such as vacuum refining method and unidirectional coagulation refining method is easy to control characteristics, and active research is being conducted because there is little contamination by impurities during operation.

Here, vacuum refining generally refers to a refining process of melting a metal raw material and removing impurities having a lower boiling point and vapor pressure from the molten metal than silicon. It is a refining process that moves (segregates) impurities to a liquid along the liquid interface.

In general, in refining through unidirectional solidification, a start block used to transfer and solidify silicon is formed in a form in which a dummy bar and a silicon button are in contact with each other.

Looking at the start block of the polysilicon manufacturing apparatus used in the prior art with reference to Figure 1 as follows.

1 is a view showing a process of manufacturing a start block of a polysilicon manufacturing apparatus used in the prior art.

First, as shown in FIG. 1A, the silicon raw material P is introduced into an upper portion of the dummy bar 12 configured to be movable up and down inside the one-way solidification part 10.

At this time, the shape or size of the silicon raw material (P) does not matter much, but in general, the junk (Chunk) form or small grain form is preferable.

Then, the electron beam is irradiated using an electron gun separately provided in the silicon raw material P injected as shown in FIG.

As such, when the high energy electron beam is irradiated onto the silicon raw material P, the silicon raw material P in a junk form is melted. When the irradiation of the high energy electron beam is irradiated, the molten silicon raw material P solidifies on the dummy bar 12 to become the silicon button 14.

The silicon button 14 is provided inside the one-way solidification part 10 together with the dummy bar 12 to be used as a start block in manufacturing polysilicon.

However, since the silicon raw material P is melted while the silicon button 14 is formed on the dummy bar 12, impurities are introduced from the dummy bar 12.

As described above, the silicon button 14 in which the impurities are introduced and the purity thereof is lowered is brought into contact with the molten silicon introduced into the one-way solidification part 10.

When the silicon button 14 into which impurities are introduced comes into contact with the molten silicon, the molten silicon is also contaminated, resulting in many problems in manufacturing high-purity polysilicon.

In addition, in the process of generating the silicon button on the dummy bar, the silicon button does not easily adhere to the dummy bar.

An object of the present invention is to solve the problem of the start block used in the prior art, to prevent the contamination of the molten silicon by using a start block made by bonding a single crystal silicon button and a graphite pile bar when manufacturing silicon through unidirectional solidification. The present invention provides a polysilicon manufacturing apparatus using a single crystal silicon button.

In order to solve the above problems, the present invention provides a vacuum chamber for maintaining a vacuum atmosphere, an electron beam irradiation unit provided in the vacuum chamber for irradiating an electron beam, a silicon raw material in the form of particles, and a region in which the electron beam is irradiated from the electron beam irradiation unit. A silicon melting part disposed in the silicon raw material by melting the silicon raw material by an electron beam, a cooling channel formed at a lower portion thereof, and a one-way solidifying part for solidifying the silicon melt supplied from the silicon melting part and inside the one-way solidifying part; And a separately manufactured start block including a single crystal silicon button for transferring the silicon melt supplied from the silicon melting part to the lower portion of the one-way solidification part and a graphite dummy bar bonded to a lower surface of the single crystal silicon button and allowing the single crystal silicon button to be moved. It includes.

The single crystal silicon button may be formed to have a predetermined pattern on the lower surface, and the graphite dummy bar may be formed to have a pattern corresponding to the lower surface of the single crystal silicon button to be bonded to each other.

In addition, the pattern may be characterized in that the contact area between the single crystal silicon button and the graphite dummy bar is formed larger than the cross section of the graphite dummy bar or the single crystal silicon button.

In addition, the single crystal silicon button may have a bottom surface formed in a pyramid shape, and the graphite dummy bar may have a top surface formed in a shape corresponding to the single crystal silicon button.

In addition, the single crystal silicon button may have a plurality of holes or a plurality of protrusions formed on a lower surface thereof, and the graphite dummy bar may have an upper surface formed in a shape corresponding to the single crystal silicon button.

In addition, the start block may be characterized in that the single crystal silicon button and the graphite pile bar are bonded through induction heating and resistance heating.

In addition, the silicon melt portion may be composed of a plurality.

In addition, the electron beam irradiation unit may be characterized in that for irradiating the electron beam on the one-way solidification unit.

The electron beam irradiator may be configured of a plurality of electron beam irradiators to irradiate the electron beam with the silicon melting portion and the one-way solidification portion.

In addition, the silicon molten portion may be characterized in that it comprises a casting vessel made of a copper material formed with a cooling channel in the lower portion.

In addition, the one-way solidification unit may be characterized in that it comprises a casting vessel made of copper formed with a cooling channel in the lower portion.

The single crystal silicon button may be formed of single crystal silicon only on an upper surface thereof.

According to the present invention to solve the above problems has the following effects.

First, in manufacturing polysilicon using a unidirectional solidification part, when manufacturing polysilicon using a start block including a graphite dummy bar and a single crystal silicon button, the single crystal silicon button manufactured separately without melting using an electron beam is graphite. Bonding with the dummy bar has an effect of preventing contamination of the molten silicon supplied to the upper portion of the single crystal silicon button.

Second, the contact surface of the single crystal silicon button and the graphite dummy bar is formed to have a constant pattern, not a general linear shape, so that the contact area is increased, so that the graphite dummy bar and the single crystal silicon button are moved when the start block moves downward along the one-way solidification part. There is an effect that can prevent the separation.

Third, the liquefied silicon molten metal is introduced into the one-way solidification unit and in contact with the single crystal silicon button, thereby producing a silicon ingot having a large particle size when the molten silicon is solidified. Therefore, since the particle size of the solidified silicon ingot decreases and the grain boundary decreases, the area to be segregated for the removal of impurities is reduced, and thus, since the segregated impurities are easily moved, the refining efficiency is increased.

1 is a view showing a process of manufacturing a start block of a conventional polysilicon manufacturing apparatus;

2 is a view showing the configuration of a polysilicon manufacturing apparatus according to an embodiment of the present invention;

3 is an exploded perspective view showing that the bonding surface of the graphite pile and the single crystal silicon button is formed in a pyramid shape in the start block of FIG.

4 is an exploded perspective view showing that the bonding surface of the graphite dummy bar and the single crystal silicon button is formed of a plurality of holes and protrusions in the start block of FIG. 2;

5 is a view illustrating a bonding process of the single crystal silicon button and the graphite pile of FIG. 2; And

FIG. 6 is a view illustrating a process of manufacturing polysilicon by the polysilicon manufacturing apparatus of FIG. 2.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, this is not intended to limit the present invention to a specific form, but to help a more clear understanding through the present embodiment.

In addition, in describing the present embodiment, the same name and the same reference numerals are used for the same configuration and additional description thereof will be omitted.

First, a configuration according to an embodiment of the present invention will be described with reference to FIG. 2 as follows.

2 is a view showing the configuration of a polysilicon manufacturing apparatus according to an embodiment of the present invention.

As shown, the configuration of the polysilicon manufacturing apparatus is largely composed of the vacuum chamber 100, the electron beam irradiation unit 200, the silicon melting portion 300 and the one-way solidification portion 400.

The vacuum chamber 100 is formed to surround the whole and has a separate vacuum pump (not shown) to adjust the vacuum state inside the vacuum pump. In addition, the raw material input unit 120 for introducing the silicon raw material (P1) on one side is provided.

The electron beam irradiation unit 200 may be provided in the vacuum chamber 100 and may be provided in plural. In the present embodiment, the electron beam irradiator 200 includes a first electron gun 210 and a second electron gun 220.

The first electron gun 210 and the second electron gun 220 are disposed on an upper end of the vacuum chamber 100 so that an electron beam is irradiated into the vacuum chamber 100.

The silicon melt part 300 is disposed in a region where the electron beam is irradiated by the first electron gun 210. In the silicon melting part 300, the silicon raw material P1 in the form of particles is introduced from the raw material input part 120, and the injected silicon raw material P1 is accelerated and integrated by the first electron gun 210. By melting, molten silicon P2 is produced. The silicon raw material P1 introduced from the raw material input part 120 is a junk type raw material, and generally has a size of about 1 mm-4 mm.

In this case, the first electron gun 210 preferably accelerates and integrates the first electron beam such that the electron beam has an output energy of 500-700 kw / m 2. When the output energy of the electron beam irradiated from the first electron gun is too high, there may be a problem that the behavior of the silicon melt P2 is unstable, such as the silicon melt P2 splashes outward by the electron beam.

In addition, the silicon melt part 300 is preferably provided with a water-cooled crucible that can block the inflow of impurities that may occur during the operation, and can easily control the cooling efficiency. Here, the water-freezing crucible is a crucible manufactured so that the cooling channel C is provided so that the crucible can withstand high temperatures using a coolant outside the crucible made of copper (Cu).

In the present embodiment, the silicon melt part 300 is configured as one, but this is not limited to a specific form, but is merely an example selected to help more clearly understood. Although the core of the present invention does not change even if the silicon melt part 300 is composed of a plurality, the user can selectively adjust the number of the silicon melt part 300.

The one-way solidification unit 400 serves to continuously cast the molten silicon (P2) and at the same time to induce segregation of metal impurities to improve silicon refining and high-purity polysilicon production efficiency.

The one-way solidification unit 400 is disposed in a region where the electron beam by the second electron gun 220 is irradiated, and is connected to the silicon melting unit 300.

In addition, the cooling channel (C) through which the cooling water for cooling the molten silicon (P2) and the like is formed in the lower portion of the one-way solidification unit 400, and the one-way solidification unit 400 is formed. Inside the 400, a start block 410 driven in a downward direction is mounted.

The start block 410 is driven downward in the one-way solidification unit 400 and serves to physically transfer the molten silicon (P2) downward while growing a mold for silicon casting.

The start block 410 is composed of a single crystal silicon button 412 and a graphite pile bar 414.

In the single crystal silicon button 412, the molten silicon P2 melted from the molten silicon 300 is introduced through an upper portion of the one-way solidification unit 400 to be in contact with the molten silicon P2.

Single crystal silicon button 412 having high purity is used to manufacture polysilicon of higher purity using the silicon molten metal P2.

The graphite dummy bar 414 may be formed of a graphite material. In particular, low density graphite is most preferred as the material of the graphite pile bar 414. When low density graphite is used as the material of the graphite dummy bar 414, a sudden temperature deviation occurs between the cooling channel C provided below the one-way solidification part 400 and the initially formed silicon melt P2. Function to prevent it.

Here, the single crystal silicon button 412 is bonded to the start block 410 instead of using only the graphite dummy bar 414. When the graphite pile bar 414 is applied, since the contamination problem such as graphite contamination of the polysilicon being cast may occur, the single crystal silicon button 412 having high purity is introduced into the silicon melt part 300. By making contact with the molten silicon (P2), it is possible to prevent contamination.

In addition, since the single crystal silicon is higher in purity than the general polycrystalline silicon, the purity of the molten silicon P2 in contact with the single crystal silicon button 412 may be increased.

As such, the silicon molten metal P2 is introduced into the one-way solidification unit 400 and contacts the single crystal silicon button 412 to produce a silicon ingot having a large particle size when the molten silicon P2 solidifies. can do. Therefore, since the particle size of the solidified silicon ingot decreases and the grain boundary is reduced, the area to be segregated for the removal of impurities is reduced, and thus the refining efficiency is increased because the segregated impurities are easily moved.

Accordingly, the single crystal silicon button 412 prevents contamination from graphite by preventing the graphite dummy bar 414 from directly contacting the molten silicon P2 or cast silicon.

On the other hand, the single crystal silicon button 412 is not composed of a single crystal as a whole, only the upper surface portion that does not contact with the graphite dummy bar may be formed of single crystal silicon. That is, the upper surface portion of the single crystal silicon button 412 is made of single crystal silicon and the lower portion is made of polycrystalline silicon, and the lower surface is bonded to the graphite dummy bar 414.

In the polysilicon manufacturing apparatus configured as described above, the start block 410 is manufactured by separately administering the silicon raw material P1 to the graphite dummy bar 414 without forming a silicon button through melting using an electron beam. The single crystal silicon button 412 is manufactured and bonded to the graphite dummy bar 414.

In this case, the graphite dummy bar 414 and the single crystal silicon button 412 bond the single crystal silicon button 412 and the graphite dummy bar 414 through induction heating and resistance heating. A bonding process of the graphite dummy bar 414 and the single crystal silicon button 412 will be described later with reference to FIG. 5.

The one-way solidification unit 400 having the start block 410 configured as described above receives the silicon melt P2 overflowed from the silicon melt 300.

In addition, the one-way solidification unit 400 supplied with the molten silicon P2 maintains the molten state of the molten silicon P2 supplied by the irradiation of the electron beam from the second electron gun 220, and the start block 410. After driving the lower to transfer the molten silicon (P2) in the lower direction, and cooling the lower portion of the molten silicon (P2) to be solidified simultaneously with the solidification from the lower portion of the molten silicon (P2) to the upper direction.

Here, the electron beam irradiated from the second electron gun 220 to the upper portion of the one-way solidification unit 400 has an output energy of 1300 ~ 2300 kW / m ² , the silicon molten metal supplied from the silicon melting part 300 It is possible to maintain the state of (P2).

Looking at the overall operation of the polysilicon manufacturing apparatus configured as described above, the silicon raw material (P1) is introduced into the silicon melt portion 300 from the raw material input portion 120 and the silicon raw material (P1) is injected into the irradiation unit By the molten silicon (P2).

While the silicon raw material P1 is continuously introduced into the silicon melt part 300, the amount of the silicon melt P2 formed in the silicon melt part 300 increases. Accordingly, the silicon melt P2 overflowed from the silicon melt part 300 is supplied to the one-way solidification part 400.

In the one-way solidification unit 400, the molten silicon P2 supplied from the silicon molten unit 300 is maintained in a molten state by an electron beam accelerated and integrated by the second electron gun 220. The molten state of the silicon molten metal P2 is maintained while being transferred downward by the start block 410 and then solidified and cast upward through the cooling channel C to form polysilicon.

The one-way solidification unit 400 may include a casting container made of copper, in which the cooling channel C is formed, similarly to a water cooling crucible.

Next, the bonding of the graphite dummy bar and the silicon button will be described with reference to FIGS. 3 and 4.

3 is an exploded perspective view showing that the bonding surface of the graphite dummy bar and the single crystal silicon button is formed in a pyramid shape in the start block of FIG. 2, and FIG. 4 is a plurality of bonding surfaces of the graphite dummy bar and the single crystal silicon button in the start block of FIG. 2. It is an exploded perspective view which shows what was formed of four holes and protrusions.

The start block 410 composed of the single crystal silicon button 412 and the graphite dummy bar 414 overflows from the silicon melting part 300 and is supplied to the one-way solidification part 400. ) Is transferred to the lower portion of the one-way solidification unit 400 in which the cooling channel C is formed to segregate and solidify the impurities contained in the molten silicon P2 and to prepare polysilicon.

Here, when the start block 410 moves to the lower portion of the one-way solidification unit 400, the graphite pile bar 414 and the single crystal silicon button 412 may be separated from each other. In order to prevent this, a predetermined pattern may be formed on the bonding surface of the single crystal silicon button 412 and the graphite dummy bar 414 to increase the bonding area of the bonding surface.

As shown in FIG. 3, the graphite pile bar 414 has a top surface formed in a pyramid shape along a lateral direction, and the single crystal silicon button 412 is formed so that the bottom surface thereof is joined to the bottom surface of the graphite pile bar 414. do.

As such, the bonding surface of the graphite dummy bar 414 and the single crystal silicon button 412 is formed in a pyramid shape and bonded to each other to form the start block 410.

Here, the single crystal silicon button 412 is not bonded to the graphite dummy bar 414 by injecting and melting the silicon raw material P1 on the graphite dummy bar 414, and separately from the outside. The single crystal silicon button 412 is manufactured and bonded to the upper portion of the graphite pile bar 414. In this case, the single crystal silicon button 412 and the graphite dummy bar 414 are bonded through induction heating and resistance heating.

As such, the bonding surface of the graphite dummy bar 414 and the single crystal silicon button 412 is formed in a pyramid shape to have a predetermined pattern, thereby bonding the graphite dummy bar 414 to the single crystal silicon button 412. Since the area becomes larger, the bonding quality of the graphite pile bar 414 and the single crystal silicon button 412 can be improved.

Next, referring to FIG. 4, a form in which the bonding surface of the single crystal silicon button 412 and the graphite dummy bar 414 is modified is as follows.

As shown in FIG. 4, the single crystal silicon button 412 has a plurality of holes 412a formed on a lower surface thereof, and a plurality of holes provided in the single crystal silicon button 412 formed on an upper surface of the graphite pile bar 414. A plurality of protrusions 414a are formed to be joined to the holes 412a.

The single crystal silicon button 412 and the graphite dummy bar 414 formed as described above are joined to the bottom surface of the single crystal silicon button 412 and the bottom surface of the graphite dummy bar 414 to form the start block.

As the holes 412a and the protrusions 414 of the single crystal silicon button 412 and the graphite dummy bar 414 are joined to each other, a bonding area of a bonding surface increases, whereby the single crystal silicon button 412 and the In addition to increasing the bonding quality of the graphite pile bar 414, it is possible to prevent the single crystal silicon button 412 from being contaminated by the graphite pile bar 414.

Here, although the plurality of holes 412a are formed in the single crystal silicon button 412 and the plurality of protrusions 414a are formed in the graphite dummy bar 414, this is not limited thereto. A plurality of protrusions may be formed in the single crystal silicon button 412 and a plurality of holes may be formed in the graphite dummy bar 414.

In addition, although not shown in the drawing, by spraying powdered graphite powder on the upper surface of the graphite dummy bar 414 to increase the roughness of the surface, the bonding of the single crystal silicon button 412 and the graphite dummy bar 414 Can improve the quality.

As described above, the embodiment of the start block 410 formed on the bonding surface of the single crystal silicon button 412 and the graphite dummy bar 414 to increase the bonding area has been described with reference to FIGS. 3 and 4. .

However, the shape of the graphite pile bar 414 and the single crystal silicon button 412 is not limited, but is selected to help a clear understanding of the present embodiment. An upper surface of the graphite dummy bar 414 and a lower surface of the single crystal silicon button 412 are formed to have a pattern so that the junction area of the graphite dummy bar 414 and the single crystal silicon button 412 may increase. If possible, any form may be applicable.

Next, referring to FIG. 5, the process of bonding the single crystal silicon button 412 and the graphite dummy bar 414 is as follows.

FIG. 5 is a view illustrating a bonding process of the single crystal silicon button and the graphite dummy bar of FIG. 2.

First, as shown in FIG. 5A, the upper surface of the graphite pile bar 414 is patterned in the form described with reference to FIGS. 3 and 4, and then the upper portion of the graphite pile bar 414 is formed. The single crystal silicon button 412 is mounted. In addition, the graphite dummy bar 414 located at the lower part is subjected to induction heating and resistance heating to transfer heat to the lower surface of the single crystal silicon button 412.

As shown in FIG. 5B, when the graphite pile bar 414 is heated, the bottom surface of the single crystal silicon button 412 is melted in a form corresponding to the top surface of the graphite pile bar 414. When the lower surface of the single crystal silicon button 412 is sufficiently melted, the heating is stopped. As such, the bottom surface of the single crystal silicon button 412 is melted and then solidified again to bond the bottom surface of the single crystal silicon button 412 in a shape corresponding to the top surface of the graphite dummy bar 414.

As such, the single crystal silicon button 412 is bonded by heating the graphite dummy bar 414 and bonding the graphite dummy bar 414 through melting of a lower surface of the single crystal silicon button 412 mounted on the upper portion. To prevent contamination from the graphite pile bar 414 that may occur in.

In this manner, in the bonding of the single crystal silicon button 412 and the graphite dummy bar 414, the bonding area of the graphite dummy bar 414 and the single crystal silicon button 412 is increased, thereby increasing the adhesive strength. Will have

Next, referring to Figure 6 with reference to the overall process for producing a polysilicon according to the present invention.

First, as shown in (a) of FIG. 6, the silicon raw material P1 is introduced into the silicon melting part 300 from the raw material input part 120, and then the electron beam is irradiated through the electron beam irradiation part 200. do. In this case, in order to melt the silicon raw material P1 using the electron beam in the electron beam irradiation unit 200, the inside of the vacuum chamber 100 should be in a high vacuum state of a predetermined level or more. Here, the silicon raw material P1 injected into the silicon melting part 300 may use the silicon raw material P1 in the form of particles having a purity of 2N and an average particle diameter of 1 to 2 mm.

As such, the silicon raw material P1 is melted by the electron beam in the vacuum chamber 100 in a high vacuum state.

In addition, the electron beam irradiation unit 200 irradiates an electron beam to the upper portion of the one-way solidification unit 400 to heat the silicon melt P2 moved from the silicon melting unit 300 so as not to be cooled.

The first electron gun 210 irradiates the first electron beam to the silicon melt part 300 from the silicon melt part 300, and the second electron gun 220 emits a second electron beam to the one-way solidification part. Irradiate to the top of 400.

As such, the silicon raw material P1 is melted by the electron beam irradiated from the electron beam irradiating part 200 inside the silicon melting part 300 to be formed as the silicon melt, and the silicon raw material as the temperature increases. The impurities contained in (P1) are volatilized and removed.

While the silicon raw material P1 is melted by the electron beam irradiated from the first electron gun 210, aluminum (Al), calcium (Ca), phosphorus (P), magnesium (Mg), and manganese (Mg) included in the silicon raw material ( Volatile impurities such as Mn) are vacuum volatilized.

Volatile impurities with a lower boiling point and vapor pressure than silicon are volatilized by high vacuum and high heating temperature by electron beam. In this case, when the electron beam output energy irradiated from the first electron gun 210 is increased and the electron beam irradiation time is increased, refining efficiency may be improved.

As described above, while the inside of the vacuum chamber 100 is maintained in a high vacuum state, the silicon melt P2 is generated in the silicon melt part 300 through the electron beam irradiation part 200, and the silicon is volatilized. Impurities in the molten metal P2 are removed.

As such, the molten silicon P2 from which impurities are removed is overflowed from the molten silicon 300 to the unidirectional solidifying part 400 as shown in FIG. 6A.

The one-way solidification unit 400 supplied with the molten silicon P2 from the molten silicon 300 transfers the start block 410 downward as shown in FIG. At this time, the second electron gun 220 is irradiated with an electron beam on the upper portion of the one-way solidification unit 400 so that the molten silicon (P2) is not immediately solidified at the upper portion of the one-way solidification unit 400.

As the start block 410 is moved downward in the one-way solidification unit 400, the molten silicon P2 in contact with the single crystal silicon button 412 is transferred downward along the single crystal silicon button 412. do.

Here, the cooling channel (C) is formed in the lower portion of the one-way solidification unit 400 to cool the lower portion of the one-way solidification unit 400.

Thus, the molten silicon P2 transferred along the start block 410 is solidified by the cooling channel C at the lower portion of the one-way solidification unit 400.

Meanwhile, the start block 410 may be driven to descend at a speed corresponding to the speed at which the silicon raw material P1 is injected from the raw material input part 120.

If the start block 410 falls at a too slow speed, the level of the molten silicon P2 is continuously raised so that process control is impossible. If the start block 410 falls at a too fast speed, the silicon melt is dropped. There is a problem that the water level of (P2) is continuously lowered, the silicon molten metal (P2) leaks to the one-way solidification unit 400 lower.

In this process, metal impurities such as iron (Fe), nickel (Ni), titanium (Ti), chromium (Cr), and copper (Cu) included in the molten silicon are moved upward along the solid-liquid interface. The segregation effect of such impurities can be sufficiently exhibited when the temperature difference between the solid and the liquid is large while the interface between the solid state and the liquid state is perpendicular to the growth direction during the silicon solidification process.

As described above, the one-way solidification part 400 grows the silicon melt P2 supplied from the silicon melt part 300 in the vertical direction through the falling of the start block 410 to manufacture polysilicon having high purity. Done.

As described above, a preferred embodiment of the present invention has been described, and in addition to the above-described embodiments, it may be embodied in other forms without departing from the spirit or scope of the present invention. Therefore, the present embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the foregoing description, and may be modified within the scope of the appended claims and their equivalents.

Claims

A vacuum chamber for maintaining a vacuum atmosphere;

An electron beam irradiator provided in the vacuum chamber to irradiate an electron beam;

A silicon molten part in which a silicon raw material in a particle form is input and disposed in a region where the electron beam is irradiated from the electron beam irradiating part so that the silicon raw material is melted by the electron beam to form a silicon melt;

A one-way solidification unit formed at a lower portion thereof to solidify the molten silicon supplied from the silicon melt portion; And

The single crystal silicon button is provided inside the one-way solidification part and manufactured separately, and is bonded to a single crystal silicon button for transferring the silicon melt supplied from the silicon melting part to the lower portion of the one-way solidification part and the lower surface of the single crystal silicon button, and the single crystal silicon button is moved. A start block including a dummy bar;

Polysilicon manufacturing apparatus using a single crystal silicon button comprising a.
The method of claim 1,

The single crystal silicon button is formed to have a predetermined pattern on the lower surface, and the graphite dummy bar is formed so that the upper surface has a pattern corresponding to the lower surface of the single crystal silicon button is bonded so as to join each other. Polysilicon production apparatus used.
The method of claim 2,

The pattern is,

Apparatus for producing polysilicon using a single crystal silicon button, characterized in that the contact area between the single crystal silicon button and the graphite pile bar is larger than the cross section of the graphite pile bar or the single crystal silicon button.
The method of claim 3, wherein

The single crystal silicon button is a polysilicon manufacturing apparatus using a single crystal silicon button, characterized in that the bottom surface is formed in a pyramid shape and the graphite dummy bar is formed in a shape corresponding to the single crystal silicon button.
The method of claim 3, wherein

The single crystal silicon button has a plurality of holes or a plurality of protrusions are formed on the lower surface, the graphite dummy bar is a polysilicon manufacturing apparatus using a single crystal silicon button, characterized in that the upper surface is formed in a form corresponding to the single crystal silicon button.
The method of claim 1,

The start block is,

Apparatus for producing polysilicon using a single crystal silicon button characterized in that the single crystal silicon button and the graphite pile bar is bonded through induction heating or resistance heating.
The method of claim 1,

The silicon melt portion,

Polysilicon manufacturing apparatus using a single crystal silicon button composed of a plurality.
The method of claim 1,

The electron beam irradiation unit,

Apparatus for producing polysilicon using a single crystal silicon button, characterized in that for irradiating the electron beam on the one-way solidification portion.
The method of claim 1,

The electron beam irradiation unit,

Apparatus for manufacturing polysilicon using a single crystal silicon button, characterized in that the plurality of pieces to irradiate the electron beam to the silicon melt portion and the one-way solidification portion.
The method of claim 1,

The silicon melt portion,

An apparatus for producing polysilicon using a single crystal silicon button, characterized in that it comprises a casting vessel made of copper formed with a cooling channel in the lower portion.
The method of claim 1,

The one-way solidification unit

Apparatus for producing polysilicon using a single crystal silicon button characterized in that it comprises a casting vessel made of a copper material formed with a cooling channel in the lower portion.
The method according to any one of claims 1 to 11,

The single crystal silicon button,

Polysilicon manufacturing apparatus using a single crystal silicon button, the upper surface is formed of single crystal silicon.