KR101620635B1 - Apparatus for producing polycrystalline silicon - Google Patents

Abstract

The apparatus for producing polycrystalline silicon according to the present invention heats the silicon mandrel 4 in the reactor 1 to which the raw material gas is supplied, thereby precipitating the polycrystalline silicon on the surface of the silicon mandrel 4. An apparatus for producing polycrystalline silicon according to the present invention has an electrode (23), an electrode holder (22), and an annular insulating material (34). The electrode 23 holds the silicon mandrel 4 in the vertical direction. The electrode holder 22 is provided with a cooling channel 27 for circulating the cooling medium therein and inserted into the through hole 21 formed in the bottom plate portion 2 of the reaction furnace 1 to hold the electrode 23 do. The annular insulating material 34 is disposed between the inner circumferential surface of the through hole 21 and the outer circumferential surface of the electrode holder 22 to electrically insulate the bottom plate portion 2 from the electrode holder 22.

A polycrystalline silicon production apparatus, an electrode, an electrode holder, a silicon mandrel,

Description

[0001] APPARATUS FOR PRODUCING POLYCRYSTALLINE SILICON [0002]

The present invention relates to a polycrystalline silicon production apparatus for producing polycrystalline silicon rods by precipitating polycrystalline silicon on the surface of a heated silicon core rod.

The present application claims priority to Japanese Patent Application No. 2008-164298, filed on June 24, 2008, and Japanese Patent Application No. 2009-135831, filed on June 5, 2009, the contents of which are incorporated herein by reference I will.

Conventionally, as a polycrystalline silicon production apparatus, it is known that it is produced by the Siemens method. In the apparatus for producing polycrystalline silicon according to the Siemens method, a plurality of silicon core rods are arranged in a reactor. The silicon core in the reaction furnace is heated, and a raw material gas composed of a mixed gas of chlorosilane gas and hydrogen gas is supplied to the reactor and brought into contact with the heated silicon mandrel. Then, the polycrystalline silicon produced by thermal decomposition of the raw material gas and hydrogen reduction is deposited on the surface of the silicon core rod.

In such a polycrystalline silicon production apparatus, the silicon core bar is fixed in a state where it is erected on the electrode disposed on the inner bottom portion of the reaction furnace. Then, the electrode is energized with the silicon mandrel, and the silicon mandrel is heated by the resistance. At this time, the raw material gas ejected from the lower side is brought into contact with the surface of the silicon mandrel to form the rod of the polycrystalline silicon. A plurality of electrodes for holding the silicon mandrel are formed so as to be dispersed over substantially the whole area of the bottom surface of the reactor. As described in Japanese Patent Application Laid-Open No. 2007-107030, And is surrounded by an insulating material.

In the above-described polycrystalline silicon production apparatus, the temperature of the gas in the reaction furnace is as high as 500 to 600 DEG C at the maximum. Thus, the electrode holder for holding the electrode is configured so that the cooling water is allowed to flow through the electrode holder. However, since the insulating material formed between the bottom plate portion of the reaction furnace and the electrode holder can not be directly cooled, the shape is easily damaged due to heat in the reaction furnace, which tends to cause deterioration of the insulating function. In this case, when a ceramic-based insulating material is used, the thermal expansion difference between the bottom plate portion of the reaction furnace and the electrode holder can not be absorbed, which may result in breakage.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polycrystalline silicon production apparatus capable of absorbing a difference in thermal expansion between a bottom plate of a reaction furnace and an electrode holder and maintaining a good insulation property.

The apparatus for producing a polycrystalline silicon of the present invention heats a silicon mandrel in a reactor furnished with a source gas, thereby precipitating the polycrystalline silicon on the surface of the silicon mandrel. An apparatus for producing a polycrystalline silicon of the present invention comprises an electrode, an electrode holder, and a ring-shaped insulating material. The electrode holds the silicon mandrel in the vertical direction. The electrode holder has a cooling passage formed therein for circulating the cooling medium, and inserted into a through hole formed in the bottom plate portion of the reaction furnace to hold the electrode. The annular insulating material is disposed between the inner peripheral surface of the through hole and the outer peripheral surface of the electrode holder to electrically insulate the bottom plate from the electrode holder. The polycrystalline silicon production apparatus of the present invention is characterized in that the electrode holder is provided with an enlarged diameter portion which is in contact with at least a part of the upper surface of the upper end portion of the annular insulating material and in which a part of the cooling passage is formed, .

The upper surface of the annular insulating material inserted into the bottom plate portion of the reactor faces the inside of the reaction furnace. Therefore, when the annular insulating material remains exposed to the inside of the reactor between the inner circumferential surface of the through hole and the electrode holder, radiation heat from the silicon core rod or the like in the reactor passes through the space between the inner circumferential surface of the through hole and the electrode holder, And directly acts on the upper end of the insulating material. According to the present invention, by forming the enlarged diameter portion in the electrode holder contacting at least a part of the upper surface of the annular insulating material, radiant heat directed to the upper surface is burdened by the electrode holder, so that radiant heat directly acting on the annular insulating material can be reduced. In addition, since the cooling medium is circulated in the enlarged diameter portion, the cooling effect of the annular insulating material can be enhanced.

In the polycrystalline silicon production apparatus of the present invention, it is preferable that the enlarged diameter portion covers the entire upper surface of the upper end portion of the annular insulating material.

In this case, by forming the enlarged diameter portion to cover the entire upper surface of the upper end portion of the annular insulating material, the radiant heat from the reactor is blocked by the enlarged diameter portion, so that the annular insulating material can be more effectively protected from the radiant heat. Further, since the entire upper surface of the upper end portion of the annular insulating material is cooled by the enlarged diameter portion, deterioration of the shape and insulating function of the annular insulating material can be prevented more effectively.

In the apparatus for producing polycrystalline silicon of the present invention, it is preferable that the cooling medium cools the vicinity of the electrodes after cooling the enlarged portion.

In this case, since the cooling portion can be kept at a low temperature by cooling the vicinity of the relatively high temperature electrode after cooling the enlarged diameter portion in which the cooling medium flowing in the electrode holder is relatively low, it is possible to more effectively prevent the annular insulation material from becoming hot can do.

In the apparatus for producing a polycrystalline silicon according to the present invention, the cooling channel includes an outer circumference-side flow path for circulating the cooling medium toward an upper end portion of the outer periphery of the electrode holder along its longitudinal direction, And an inner circumferential flow path for flowing the cooling medium toward the lower end of the electrode holder along the longitudinal direction, wherein a part of the outer circumferential flow path is formed in the enlarged diameter portion.

In this case, the cooling medium flows from the outer peripheral portion of the electrode holder toward the upper end, and then flows from the inside toward the lower end, thereby efficiently cooling the electrode holder to the upper end portion.

Further, in the apparatus for producing a polycrystalline silicon of the present invention, it is preferable that the annular insulating material is made of a resin having elasticity. In this case, breakage of the annular insulating material due to the difference in thermal expansion between the bottom plate portion and the electrode holder is prevented, and the thermal expansion difference between the bottom plate portion and the electrode holder is absorbed by the annular insulating material, Is prevented.

According to the apparatus for producing a polycrystalline silicon of the present invention, since the enlarged portion formed in the electrode holder blocks the radiant heat from the silicon mandrel to the annular insulating material and cools the annular insulating material, the annular insulating material is effectively protected So that the insulation and elasticity of the annular insulating material can be satisfactorily maintained. Therefore, a synthetic resin or the like can be used as the annular insulating material, and the thermal expansion difference can be absorbed while ensuring insulation between the bottom plate portion and the electrodes, thereby maintaining the integrity of the entire apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of a polycrystalline silicon production apparatus of the present invention will be described with reference to the drawings.

[First Embodiment]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an overall view of a polycrystalline silicon production apparatus to which the present invention is applied. The reaction furnace 1 of the apparatus for producing polycrystalline silicon comprises a bottom plate 2 constituting a furnace bottom and a bell jar 3 bell mounted on the bottom plate 2 so as to be freely detachable. and a bell jar. The upper surface of the bottom plate portion 2 is formed as a substantially flat horizontal surface. Since the ceiling is dome-shaped, the inner space of the bell jar 3 has the highest central portion and the lowest outer peripheral portion. Further, the walls of the bottom plate portion 2 and the bell jar 3 are formed into a jacket structure (not shown), and are cooled by cooling water.

A plurality of electrode units 5 to which the silicon mandrel 4 is mounted and an ejection nozzle (gas supply port) 6 for ejecting a raw material gas containing chlorosilane gas and hydrogen gas into the furnace are provided in the bottom plate portion 2, And a gas discharge port 7 for discharging the gas after the reaction to the outside of the furnace.

The raw material gas spouting nozzle 6 is dispersed in the almost entire region of the upper surface of the bottom plate portion 2 of the reaction furnace 1 so as to supply the raw material gas uniformly to each silicon mandrel 4, Is installed. These jet nozzles 6 are connected to a source gas supply source 8 outside the reaction furnace 1. A plurality of gas outlets 7 are provided at appropriate intervals in the circumferential direction in the vicinity of the outer circumferential portion on the bottom plate portion 2 and are connected to an exhaust gas processing system 9 on the outside. To the electrode unit 5, a power supply circuit 10 is connected. The bottom plate portion 2 has a jacket structure, and a cooling channel (not shown) is formed therein.

The lower end of the silicon mandrel 4 is fixedly inserted in the electrode unit 5 so that it extends upward and is installed so as to be paired. A member 12 is mounted. This connecting member 12 is also formed of the same silicon as the silicon mandrel 4. The seed assembly 13 is assembled such that the two silicon mandrels 4 and the connecting members 12 connecting them form a U-shape (inverted U-shape) as a whole. Since the electrode unit 5 is arranged concentrically from the center of the reaction furnace 1, the seed assembly 13 is arranged almost concentrically from the center of the reaction furnace 1.

Specifically, as shown in Fig. 2, an electrode unit 5A for a single silicon core, which holds the single silicon mandrel 4 as the electrode unit 5 in the reactor 1, And an electrode unit 5B for a two-core silicon mandrel holding the stem 4 is disposed.

As shown in Fig. 2, the electrode unit 5A for a single silicon core and the electrode unit 5B for a silicon core unit for two silicon cores are made up of, for example, three sets of the seed assemblies 13 as one unit, . At this time, from the end of the unit row, one electrode unit 5A for a single silicon core, two electrode unit 5B for a silicon core bar 5B, and one electrode unit 5A for a silicon core bar They may be listed in order. In this case, three sets of seed assemblies 13 are formed so as to extend between the four electrode units 5A and 5B. Both silicon mandrels 4 of one seed assembly 13 are held by adjacent electrodes.

That is, one of the two silicon mandrels 4 of the seed assembly 13 is held in the electrode unit 5A for one silicon core bar, and two sets of seed assemblies 13 are held one by one. Then, the power cable is connected to the electrode unit 5A for the single silicon core at both ends of the heat so that current flows. At this time, in the electrode unit 5B for a two-core silicon core, a current flows between the both electrodes 47 via the arm portion 42 (see Fig. 4).

As described above, the electrode unit 5A for one silicon core bar holding two silicon mandrels 4 and the electrode unit 5B for two silicon mandrels for holding two silicon mandrels 4 in two, It is possible to reduce the number of electrode units (for example, about 2/3), compared to the case where all of them are held one by one. When the number of electrode units is small in this way, the through holes formed in the bottom plate portion 2 of the reactor 1 can also be reduced, and the bottom plate portion 2 can be held in a rigid structure. In addition, since many silicon mandrels 4 can be held with a small number of electrode units, a large number of silicon mandrels 4 can be provided in the reactor 1, and productivity can be enhanced. In addition, since the number of electrode units is small, the number of cooling pipes and power cables disposed under the bottom plate 2 can be reduced, and the maintenance workability is improved.

Next, the details of each electrode unit structure will be described.

First, a description will be given of the electrode unit 5A for a single silicone core holding the single silicon mandrel 4. As shown in Fig. 3, the electrode unit 5A is composed of an electrode holder 22 and an electrode 23. The electrode holder 22 is inserted into the through hole 21 formed in the bottom plate portion 2 of the reaction furnace 1 and the electrode 23 is formed at the upper end of the electrode holder 22, 4).

As shown in Fig. 3, the electrode holder 22 is formed into a bar shape by a conductive material such as stainless steel. The electrode holder 22 is formed integrally with a straight rod portion 24, a hollow disk-shaped large diameter portion 25, and a male screw portion 26. The straight rod portion 24 is inserted into the through hole 21 along the vertical direction. The diameter-enlarged hollow portion 25 is formed coaxially with the electrode holder 22 and is formed at the upper end portion of the straight rod portion 24 and has a larger diameter than the rod portion 24. In the inside of the enlarged diameter portion 25, the original space 25a is formed coaxially with the electrode holder 22, and the space 25a is larger in diameter than the rod portion 24. The male screw portion 26 protrudes further upward from the upper surface of the enlarged diameter portion 25 thereof. A male threaded portion 28 is formed at a position protruding from the bottom plate portion 2 below the rod portion 24.

The electrode holder 22 is hollow. The electrode holder 22 has an inner diameter smaller than the inner diameter of the electrode holder 22 and an inner cylinder 30 interposed between the outer periphery of the electrode holder 22 and the inner periphery of the electrode holder 22, And is coaxial with the electrode holder 22. The upper end of the inner cylinder 30 abuts against the inner surface of the upper end of the electrode holder 22 and an opening 30a communicating the inner and outer sides of the inner cylinder 30 is formed at the upper end. The outer circumferential passage 27A formed between the inner barrel 30 and the electrode holder 22 and the inner barrel 30 are formed in the electrode holder 22 from the rod portion 24 to the male screw portion 26. [ And the inner passage 27B formed in the inner circumferential surface of the inner passage 27B is communicated with the opening 30a. A cooling medium flows through the cooling channel (27).

A ring plate 31 is formed on the outer peripheral surface of the inner cylinder 30 so as to be substantially perpendicular to the inner cylinder 30 at a position corresponding to the inner space 25a of the enlarged diameter portion 25. The ring plate 31 guides the flow direction of the cooling medium flowing in the outer circumferential flow path 27A into the space 25a in the enlarged diameter portion 25. A plate-like spacer 32 for securing an interval between the inner circumferential surface of the electrode holder 22 and the outer circumferential surface of the inner tube 30 at a position corresponding to the male screw portion 28 is formed on the outer circumferential surface of the inner tube 30, 30 extending in the axial direction.

On the other hand, the through hole 21 of the bottom plate portion 2 in which the electrode holder 22 is inserted has a tapered portion 21B whose lower portion is the straight portion 21A and whose upper portion is gradually enlarged toward the upper side . The inner diameter of the straight portion 21A is formed to be larger than the outer diameter of the rod portion 24 of the electrode holder 22. As a result, a ring-shaped space is formed around the rod portion 24. The tapered portion 21B is formed at an inclination angle of 5 DEG to 15 DEG with respect to the vertical axis, for example. A spot faced portion 33 is formed in the upper end opening of the tapered portion 21B so as to be larger in diameter than the maximum inner diameter of the tapered portion 21B.

An annular insulating material 34 is formed so as to surround the electrode holder 22 between the inner peripheral surface of the through hole 21 and the rod portion 24 of the electrode holder 22. The annular insulating material 34 is formed of an insulating resin having elasticity and a high melting point, such as a fluorine resin typified by polytetrafluoroethylene (PTFE) or a perfluoroalkoxyalkane (PFA). The annular insulating material 34 has a flange-attached sleeve 35 inserted in the straight portion 21A of the through hole 21 and a cone member 36 disposed in the tapered portion 21B of the through hole 21. [ As shown in Fig. For example, the PTFE used as the material of the annular insulating material 34 has a melting point (ASTM standard: D792) of 327 DEG C, a flexural modulus (ASTM standard: D790) of 0.55 psi, a tensile modulus of elasticity (ASTM standard: D638) of 0.44 to 0.55 And the coefficient of linear expansion (ASTM standard: D696) is 10 × 10 ^-5 / ° C.

The outer surface of the cone member 36 is formed into a tapered shape having the same inclination angle as the inner circumferential surface of the tapered portion 21B of the through hole 21. [ The cone member 36 is inserted into the through hole 21 from above the bottom plate portion 2 and abuts against the inner surface of the tapered portion 21B. The lower surface of the enlarged portion 25 of the electrode holder 22 is in contact with the upper surface of the upper end of the cone member 36. The diameter of the enlarged diameter portion 25 is set to be substantially equal to or slightly smaller than the maximum outer diameter of the cone member 36 or the outer diameter of the upper surface of the upper end portion. Covering the whole. When the distance between the enlarged diameter portion 25 and the side face of the spot facing portion 33 is sufficiently large so as not to be short-circuited, the outer diameter of the enlarged diameter portion 25 is set to be smaller than the outer diameter of the upper surface of the upper end portion of the cone member 36 Can be made slightly larger. On the other hand, when the distance between the enlarged diameter portion 25 and the side face of the spot facing portion 33 is short, the outer diameter of the enlarged diameter portion 25 can be made slightly smaller than the outer diameter of the upper end portion of the upper end portion of the cone member 36 .

An O-ring 43 is formed on the inner peripheral portion of the outer circumferential surface and the upper end surface of the cone member 36, respectively. The airtightness between the cone member 36 and the electrode holder 22 and the bottom plate 2, that is, the airtightness in the through-hole 21 of the reaction furnace 1 is maintained by these O-

The sleeve 35 having the flange is inserted into the straight portion 21A so that the flange portion 37 integrally formed at the lower end thereof abuts against the rear surface of the bottom plate portion 2 of the reaction furnace 1. The upper surface of the flange portion 37 is pressed against the back surface of the bottom plate portion 2 by the nut 38 fitted in the male screw portion 28 of the electrode holder 22. [ A ring washer 39a, a disc spring 39b, and a ring washer 39a are disposed in this order between the lower surface of the flange portion 37 and the nut 38. [ When the upper surface of the flange portion 37 is pressed by the nut 38 to the back surface of the bottom plate portion 2, a suitable pressure is set by the diaphragm spring 39b. It is preferable that the ring washer 39a is made of stainless steel (SUS304), and the dish spring 39b is made of stainless steel (SUS631).

The electrode holder 22 is pulled downward with respect to the bottom plate portion 2 and the gap between the diameter portion 25 and the nut 38 is reduced by tightly tightening the nut 38, And the annular insulating member 34 is sandwiched therebetween. The outer circumferential surface of the cone member 36 is pressed against the inner circumferential surface of the tapered portion 21B of the through hole 21 by the fitting force so that the annular insulating member 34 and the electrode holder 22 come into contact with the bottom plate portion 2, As shown in Fig. At this time, the lower portion of the enlarged diameter portion 25 approaches the bottom plate portion 2 while checking the height position of the lower surface of the enlarged diameter portion 25 of the electrode holder 22 (the protrusion height from the surface of the lower plate portion 2) . At this time, the amount of fitting of the nut 38 is adjusted so that electrical shorting does not occur between the lower portion of the enlarged diameter portion 25 and the bottom plate portion 2.

The elastic deformation of the plate spring 39b and the annular insulating material 34 (the sleeve 35 and the cone member 36 with the resin flange attached thereto) Relative movement in the vertical direction is permitted. Therefore, the difference in thermal expansion between the electrode holder 22 and the bottom plate portion 2 is absorbed.

The upper end of the cone member 36 of the annular insulating member 34 protrudes slightly above the upper end of the tapered portion 21B of the through hole 21 and faces the spot facing portion 33. [ The cone member 36 is formed so that its upper end protrudes from the bottom surface of the spot facing portion 33 and is not protruded upward beyond the upper end of the spot facing portion 33, Is set to be larger than the maximum outside diameter.

On the other hand, the electrode 23 is formed in a cylindrical shape as a whole by carbon or the like. The electrode 23 has a female screw portion 43 which is fitted in the male screw portion 26 of the electrode holder 22 at its lower end and a hole 23a for fixing the silicon mandrel 4 in an inserted state , And the hole 23a is formed along the axis.

(1) The cooling flow path 27 formed in the electrode unit 5A for a silicon core will now be described. As shown in Fig. 3, the cooling medium flows into the outer circumferential passage 27A through the inlet 127A formed in the lower end of the electrode holder 22, and flows upward. The cooling medium is guided by the ring plate 31 to flow through the space 25a in the enlarged diameter portion 25 and then reaches the vicinity of the inside of the male screw portion 26, The cooling medium flows into the inner cylinder 30 from the opening 30a formed in the upper end of the inner cylinder 30 when the inside of the outer cylinder 27A is filled with the inside of the outer cylinder 27A. Thereafter, the cooling medium flows downward in the inner cylinder 30, that is, the inner circumferential passage 27B, and flows out from the outlet 127B formed at the lower end of the inner cylinder 30 to the outside of the electrode holder 22 . In other words, the cooling medium cools the enlarged diameter portion 25 during the flow of the outer-side flow path 27A, then cools the vicinity of the relatively high-temperature electrode 23, And is discharged from the holder 22.

[Second Embodiment]

The electrode unit 5B for two silicon cores will be described. The electrode unit 5B for two silicon cores is shown in an enlarged manner in Fig. The electrode unit 5B for the present silicon core has an electrode holder 46 formed in a through hole 21 formed in the bottom plate 2 of the reactor 1 and an electrode holder 46 formed on the upper end of the electrode holder 46 And the electrode 47 formed is the same as the electrode unit 5A for a single silicon core bar. The electrode unit 5B for the present silicon core bar is structured such that the electrode holder 46 is branched into two bifurcations at the upper end portion and the electrodes 47 are formed at both ends of the electrode holder 46, And is different from the rod electrode unit 5A.

The electrode holder 46 of the electrode unit 5B has a structure in which a bar portion 41 forming a rod and an arm portion 42 orthogonal to the upper end of the bar portion 41 are integrally formed. The electrode holder 46 is formed of a conductive material such as stainless steel. At the intermediate position in the longitudinal direction of the rod portion 41, a hollow-ring-shaped, enlarged diameter portion 45 is formed. A male threaded portion 46a similar to the male threaded portion 28 in the first embodiment is formed at a position where the rod portion 41 protrudes from the lower surface of the bottom plate portion 2.

The through holes 21 (the straight portion 21A and the tapered portion 21B) of the bottom plate portion 2 in which the electrode holder 46 is inserted and the spot faces 21a formed in the upper openings of the tapered portions 21B An annular insulating member 34 (a flange-attached sleeve 35, a cone member 36) formed between the inner peripheral surface of the through hole 21 and the rod portion 41 of the electrode holder 46, The nut member 38 and the ring washer 39a threadedly engaged with the male thread portion 46a of the rod portion 41 have the same configuration and effect as those of the electrode unit 5A for one silicone core bar. It is omitted.

The arm portion 42 of the electrode holder 46 horizontally extends from the upper end of the rod portion 41 horizontally to form a T-shape together with the rod portion 41. The arm portion 42 is formed with a female screw hole 42a through which the electrodes 47 pass through in the vertical direction. The electrode 47 is screwed to the female screw hole 42a and exposed to the upper portion of the arm portion 42. [ A nut member 44 is attached to a proximal end portion of the electrode 47 on the arm portion 42. The nut member 44 is formed in a cylindrical shape, and a female screw portion is screwed to the electrode 47 at its inner peripheral portion. The nut member 44 is preferably formed of carbon or the like.

The arm portion 42 is provided with a straight inner space 42b extending in the left and right direction and a circular arc 42a surrounding the outer periphery of each female screw hole 42a in a C shape and communicating with the straight inner space 42b, Shaped inner space 42c is formed. The straight-shaped inner space 42b is vertically partitioned by the third partition plate 48C.

The upper space of the rod portion 41 of the electrode holder 46 is partitioned into the left space 41c and the right space 41d by the second partition plate 48B connected to the third partition plate 48C have. The first partition plate 48A is connected to the lower end of the second partition plate 48B so as to be substantially perpendicular to the axial direction of the rod portion 41 and to divide the inside of the rod portion 41 into upper and lower portions. The first partition plate 48A is provided with a through hole 148A which is opened only to the right of the second partition plate 48B. The bar portion 41 is provided with a first opening 41a formed below the first partition plate 48A and a second opening 41b formed above the first partition plate 48A and extending from the first opening 41a to the rod portion 41 And a second opening 41b formed on the opposite side of the axis by 180 degrees.

The enlarged diameter portion 45 is an annular member that forms an annular space 45b on the outer circumferential surface of the rod portion 41 by fitting to the outer peripheral surface of the rod portion 41. [ The annular space 45b in the enlarged diameter portion 45 has a first opening 41a opened downwardly of the first partition plate 48A and a second opening 45a opened upward of the first partition plate 48A 41b. In addition, a circumferential wall portion 45a is formed on the outer peripheral portion of the upper surface of the enlarged diameter portion 45 in a rounded shape.

An inner cylinder 49 communicating with the right space 41d through the through hole 148A is attached to the lower surface of the first partition plate 48A in a substantially coaxial manner with the rod portion 41. [ The inner cylinder 49 has a space in the outer circumferential side (the outer circumferential side channel 40A) and a space in the inner circumferential side (the inner circumferential channel 40B) inside the rod portion 41 below the first partition plate 48A, ).

By forming the electrode unit 5B for a two-core silicone core as described above, the electrode holder 46 is provided with the outer circumferential passage 40A and the inner circumferential passage 40B and the neck portion 45 below the rod portion 41, Shaped space 42b and the arcuate inner space 42c of the arm portion 42 are formed by the annular space 45b of the rod portion 41 and the left space 41c and the right space 41d of the rod portion 41, A cooling passage 40 is formed.

In the cooling channel 40, the cooling medium flows from the lower end of the electrode holder 46 into the outer circumferential side channel 40A formed between the outer circumferential face of the inner cylinder 49 and the inner circumferential face of the rod portion 41, do. Upon reaching the first partition plate 48A, the cooling medium is blocked by the first partition plate 48A and flows into the annular space 45b in the enlarged diameter portion 45 through the first opening 41a, Thereby cooling the diameter portion 45. Thereafter, the cooling medium flows through the second opening 41b to the upper side of the first partition plate 48A and to the left side of the second partition plate 48B, that is, to the left space 41c.

The cooling medium introduced into the left space 41c is circulated from the lower left side of the straight internal space 42b of the arm portion 42 by the second partition plate 48B and the third partition plate 48C to the left circular arc shape And is guided to the inner space 42c. Thereafter, the cooling medium flows through the upper side of the third partition plate 48C in the straight-shaped inner space 42b and flows through the right circular arc-shaped inner space 42c to the right lower side of the straight- . The cooling medium cools the vicinity of the electrode 47 in the meantime. When the cooling medium flows through the right space 41d along the second partition plate 48B and reaches the first partition plate 48A, the cooling medium flows through the through hole 148A to the inner peripheral side flow path 40B and is discharged from the electrode holder 46. [

When the silicon mandrel 4 is energized in each of the electrode units 5 (the electrode unit 5A and the electrode unit 5B) in the polysilicon manufacturing apparatus configured as described above, the silicon mandrel 4 is brought into the resistance heating state Also, radiant heat from adjacent silicon mandrels 4 is received between the silicon mandrels 4, and they are mutually heated, and they are elevated to a high temperature state. The source gas brought into contact with the surface of the silicon stem (4) at the high temperature reacts to precipitate the polycrystalline silicon.

Radiant heat from the silicon mandrel 4 also acts on the electrode unit 5A and the electrode unit 5B on the bottom plate 2 of the reactor 1. The heat of the annular insulating material 34 weak in heat, It is considered that some of them will be affected by the heat since they are exposed in the spot facing portion 33. 3 and 4, the enlarged diameter portion 25 of the electrode holder 22 and the enlarged diameter portion 45 of the electrode holder 46 are respectively formed on the upper surface of the upper end portion of the annular insulating material 34, So that the radiant heat directly acting on the top surface is small. In addition, since the electrode holder 22 and the electrode holder 46 are cooled by the cooling medium flowing in the inside, the annular insulating material 34 is also effectively cooled. Particularly, the annular insulating material 34 is effectively cooled by flowing the cooling medium into the space formed inside the enlarged diameter portion 25 and the enlarged diameter portion 45 covering the upper surface of the upper end portion.

Thus, even in the high-temperature reaction furnace 1, the annular insulating material 34 is prevented from being deformed or deteriorated due to high temperature and retains its elasticity, so that the thermal deformation of each member can be absorbed, So that the function of the equipment can be appropriately maintained.

In addition, the present invention is not limited to the configuration of the above-described embodiment, and various modifications can be added to the detailed configuration within the scope not departing from the gist of the present invention.

For example, the enlarged portion of the electrode holder may not necessarily cover the entire upper surface of the upper surface of the annular insulating material, but may be formed so as to cover at least a part of the upper surface of the annular insulating material so as to prevent deformation or deterioration of the annular insulating material. .

In the above embodiment, only one cooling flow path is formed, but a cooling flow path for cooling the large diameter portion and a cooling flow path for cooling the vicinity of the electrode may be separately formed.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. The invention is not limited by the foregoing description, but is only limited by the scope of the appended claims.

Fig. 1 is a perspective view showing a part of the bellows of the reactor. Fig.

2 is a cross-sectional view of the reactor shown in Fig.

3 is an enlarged cross-sectional view showing an electrode unit for a single silicon core in the reactor shown in Fig. 2;

4 is an enlarged cross-sectional view showing a main part of an electrode unit for a double silicon core in the reactor shown in Fig. 2;

[Description of Drawings]

1: Reaction furnace

2:

4: silicon mandrel

5, 5A, 5B: electrode unit

21: Through hole

22, 46: electrode holder

23, 47: electrode

25, 45:

27, 40: cooling channel

27A, 40A: outer peripheral side flow path

27B, 40B: inner peripheral side oil passage

34: annular insulator

Claims (5)

A polycrystalline silicon producing apparatus for producing a polycrystalline silicon by depositing a polycrystalline silicon on the surface of a silicon core rod by heating a silicon mandrel in a reaction furnace supplied with a raw material gas, An electrode for vertically extending the silicon mandrel; An electrode holder formed inside the cooling channel for circulating the cooling medium and inserted into the through hole formed in the bottom plate portion of the reaction furnace and holding the electrode, And an annular insulating material disposed between the inner peripheral surface of the through hole and the outer peripheral surface of the electrode holder to electrically insulate the bottom plate from the electrode holder, Wherein the electrode holder is formed on the outer circumferential surface of the electrode holder so as to contact at least a part of the upper surface of the upper end of the annular insulating material and to have a large diameter portion in which a part of the cooling passage is formed. The method according to claim 1, And the enlarged portion covers the entire upper surface of the upper end portion of the annular insulating material. The method according to claim 1, Wherein the cooling medium cools the vicinity of the electrode after cooling the enlarged diameter portion. The method according to claim 1, Wherein the cooling passage includes an outer circumferential flow path for allowing the cooling medium to flow through the outer periphery of the electrode holder toward the upper end thereof along the longitudinal direction thereof and an inner circumferential flow path for guiding the inside of the outer circumferential flow path toward the lower end of the electrode holder along the longitudinal direction Side flow passage for circulating the cooling medium, and a part of the outer-side flow passage is formed in the enlarged diameter portion. The method according to claim 1, Wherein the annular insulating material is made of a resin having elasticity.

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