JP2012132522A - High-temperature valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-temperature valve device of a simple configuration, which can exhibit high corrosion resistance, and can mechanically separate a reaction by-product and a material for reaction when producing silicon while maintaining them in a gas state completely different from the phase state of solid silicon.SOLUTION: A high-temperature valve device 40, 140, which can be positioned under a reactor 10 for generating silicon, is provided with: a first tube-shaped member connected to the interior space of the reactor, and capable of introducing silicon generated in the reactor; a valve positioned in the first tube-shaped member; and a heater 100 capable of heating a heating region including the valve and part of the first tube-shaped member from the reactor to the valve to a temperature greater than or equal to the boiling point of the related substances pertaining to the generation of silicon in the reactor.

Description

  The present invention relates to a high-temperature valve device, and more particularly to a high-temperature valve device into which corrosive gas flows in addition to a reaction product at a high temperature.

  In general, as a valve for controlling the flow rate at a high temperature, a butterfly valve for controlling the flow rate of a high-temperature fluid blown toward the steelmaking blast furnace or a high-temperature high-pressure fluid discharged from the ironmaking blast furnace is used. In recent years, various configurations have been proposed in order to improve the heat resistance of the butterfly valve.

  Patent Document 1 relates to a high-temperature butterfly valve, in which a ceramic valve body is rotatably supported in a fluid flow path of a casing, and the casing has a metal case and a heat insulating layer formed inside the casing. A structure is proposed in which the heat insulating layer has an outer layer made of a refractory having excellent heat resistance and an inner layer made of a high-strength refractory.

  Patent Document 2 relates to a flow control valve for a high-temperature fluid, and has a heat insulation layer having an inner layer made of a high-strength refractory and an outer layer made of an indefinite refractory excellent in heat resistance, inside a metal case. In addition, a configuration is proposed in which a valve body having a ceramic valve plate is disposed in the flow path, and only the valve shaft is supported by a heat insulating layer, or the valve body and a joint of the drive unit are connected by shrink fitting.

  Patent Document 3 relates to a high-temperature butterfly valve. In a butterfly valve in which a valve body is attached to a valve shaft that is inserted perpendicularly to a cylinder axis in the middle of a cylinder axis direction of a valve box having an outer cylinder and an inner cylinder. Protrusions are provided at both ends of the inner periphery and the outer periphery of the inner cylinder in the cylinder axial direction, the inner cylinder is supported in a simple beam shape at both ends of the outer cylinder, and a heat insulating material is disposed between the two. In addition, a configuration is proposed in which the material of the inner cylinder and the material of the valve body are made of the same material such as stainless steel or high chromium cast steel.

Japanese Utility Model Publication No. 60-77856 JP-A-4-285368 JP 2004-138202 A

  However, according to the study of the present inventor, the configurations proposed in Patent Document 1 and Patent Document 2 have a configuration in which a heat-resistant heat-insulating layer is arranged inside the metal case. Although it is excellent, there is no disclosure or suggestion regarding the configuration for forcibly heating the flow path and the valve body from the outside to the valve body.

  Moreover, in the structure proposed by patent document 3, since it has the structure which has arrange | positioned the heat insulating material between the outer cylinder and inner cylinder of the valve box, the flow path and valve body which forcibly reach from the outside to a valve body No disclosure or suggestion has been made regarding the structure for heating. Furthermore, since it has a structure in which the material of the inner cylinder and the material of the valve body are made of the same material such as stainless steel, high chrome cast steel, etc., it tends to be difficult to use for fluids that are corrosive to iron and the like. Is expensive.

Here, according to a further study by the present inventors, when high-purity silicon is produced by a chemical process, in addition to the reaction product silicon and its reaction by-product, which are production objects, a reaction product is used. There is a possibility that an event to be sent to the silicon take-out part may occur in a state where the raw material is mixed.

  In such a case, it is desirable to efficiently separate reaction by-products and reaction raw materials from the reaction product silicon, which is an object of production, using a valve device with a simple configuration. Since the raw materials of these materials are highly corrosive, countermeasures are required, and when they are sent toward the silicon take-out part, they become solid as well as polycrystalline silicon, and are mixed into silicon. Therefore, it is also required to heat and maintain the reaction by-products and reaction raw materials in a gas state completely different from solid silicon and mechanically separate them with a valve device.

  In other words, at present, high corrosion resistance is realized, and mechanically separated while maintaining the reaction by-products and reaction raw materials for producing silicon in a gas state completely different from that of solid silicon. There is a long-awaited situation for a new configuration of a high temperature valve device that can do this.

  The present invention has been made in view of such circumstances, and can exhibit high corrosion resistance, and a reaction by-product and a raw material for reaction when producing silicon can be completely different from solid silicon in a gas phase state. An object of the present invention is to provide a high-temperature valve device that can be mechanically separated while maintaining a state.

  In order to achieve the above object, a high-temperature valve device according to the first aspect of the present invention is a high-temperature valve device that can be disposed below a reactor that generates silicon, and communicates with the internal space of the reactor. And a first tubular member into which silicon produced in the reactor can be introduced, a valve disposed in the first tubular member, and the first tubular member extending from the reactor to the valve. And a heater that can be heated to a temperature higher than the boiling point of a related substance related to silicon generation in the reactor.

  According to the present invention, in addition to the first aspect, the first tubular member includes a longitudinal outer tube extending in a first direction parallel to the vertical direction, and a second perpendicular to the first direction. The second aspect is that the valve is provided in a second tubular member that extends rotatably in the horizontal outer tube.

  In addition to the second aspect, the present invention further includes an inert gas supply mechanism for supplying an inert gas to a gap portion defined between the lateral outer tube and the second tubular member. The third aspect is to provide.

  In addition to any one of the second to third aspects, the present invention provides that the second tubular member is rotatably disposed in the lateral outer tube via a ground seal. Let's say that.

  In addition to the fourth aspect of the present invention, a fifth aspect is that the ground seal is disposed outside the heating region of the heater.

  According to the present invention, in addition to any one of the second to fifth aspects, the second tubular member is closed at one end which is a wall continuous to the valve and at the other end facing the one end. It is a sixth aspect of the present invention to have a formed inner pipe, and the other end portion has a communication hole that communicates the internal space of the inner pipe to the outside.

In addition to any one of the second to sixth aspects of the present invention, the horizontal outer tube has a diameter-expanding portion obtained by expanding the horizontal outer tube, and the vertical outer tube and the horizontal outer tube. Are connected to each other through the enlarged diameter portion as a seventh aspect.

  In addition to any one of the third to seventh aspects, the present invention provides the inert gas supply mechanism including an annular flow path member provided in the lateral outer pipe, and the inert gas supply mechanism An eighth aspect is that the inert gas to be supplied is supplied to the gap through the internal space of the annular flow path member.

  According to the present invention, in addition to any one of the third to eighth aspects, the inert gas supply mechanism includes a chamber tube fixed to a side plate that closes one end of the lateral tube, The ninth aspect is that the inert gas supplied from the active gas supply mechanism is further supplied to the inner space of the lateral outer tube via the chamber tube.

  According to the present invention, in addition to any one of the first to ninth aspects, the related substance is introduced into the first tubular member via a funnel-shaped guide member provided in the reactor. This is the tenth aspect.

  In addition to any one of the first to tenth aspects, the present invention has an eleventh aspect in which the related substance contains zinc and zinc chloride.

  According to the high-temperature valve device in the first aspect of the present invention, the reactor includes a portion extending from the reactor of the first tubular member to the valve disposed in the first tubular member and a heating region including the valve. By providing a heater that can be heated above the boiling point of the related substances related to silicon production, it has a simple structure with high corrosion resistance, and is a reaction by-product and raw material for reaction when producing silicon. Substances can be mechanically and efficiently separated while maintaining a gas state that is in a completely different phase from that of solid silicon, which can contribute to the production of silicon with reduced contamination of such related substances.

  According to the configuration of the second aspect of the present invention, the first tubular member extends in the first direction parallel to the vertical direction, and the second direction perpendicular to the first direction. A horizontal tube that extends, and a valve is provided on the second tubular member that extends rotatably in the horizontal tube, so that quartz glass can be suitably used, and heat resistance is improved. It is possible to realize a high-temperature valve device with high resistance and corrosion resistance and contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the third aspect of the present invention, by further including an inert gas supply mechanism that supplies an inert gas to a gap portion defined between the lateral outer tube and the second tubular member. Thus, it is possible to realize a highly reliable high-temperature valve device that has a simple structure and does not unnecessarily adhere to the valve, and can contribute to the production of silicon with reduced contamination of related substances during silicon production.

  According to the configuration of the fourth aspect of the present invention, the second tubular member is rotatably disposed in the lateral outer tube via the ground seal, so that the inside of the valve device can be externally provided with a simple configuration. Therefore, it is possible to realize a high-temperature valve device having a highly reliable valve that can rotate while being properly sealed, and can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

According to the configuration of the fifth aspect of the present invention, the gland seal is disposed outside the heating region of the heater, thereby having a highly reliable valve that is rotatable while maintaining high durability of the gland seal. A high-temperature valve device can be realized, which can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the sixth aspect of the present invention, the second tubular member has an inner tube closed at one end which is a wall portion connected to the valve and the other end facing the one end, and the other end High-temperature valve having a highly reliable valve that can suppress the pressure in the inner space of the inner pipe from being unnecessarily increased and damaged by having a communication hole that communicates the inner space of the inner pipe with the outside. An apparatus can be realized and can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the seventh aspect of the present invention, the horizontal outer tube has a diameter-expanded portion obtained by expanding the horizontal outer tube, and the vertical outer tube and the horizontal outer tube are connected to each other via the diameter-expanded portion. As a result, it is possible to realize a high-temperature valve device having a highly reliable and rotatable valve with an easy assembly that can suitably use quartz glass, and mixing of related substances during silicon production. This can contribute to the production of silicon with reduced.

  According to the configuration of the eighth aspect of the present invention, the inert gas supply mechanism has the annular flow path member provided in the lateral outer tube, and the inert gas supplied from the inert gas supply mechanism is an annular flow. Reliability that the valve is not fixed unnecessarily by being supplied more uniformly to the gap defined between the lateral outer tube and the second tubular member via the internal space of the passage member A high-temperature valve device with high temperature can be realized easily and reliably, and can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the ninth aspect of the present invention, the inert gas supply mechanism has a chamber tube fixed to a side plate that closes one end of the lateral outer tube, and is supplied from the inert gas supply mechanism. The gas is supplied more uniformly to the gap defined between the lateral outer tube and the second tubular member and the inner space of the lateral outer tube through the chamber tube, so that the valve A highly reliable high-temperature valve device that does not need to be fixed unnecessarily can be realized easily and reliably, and can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the tenth aspect of the present invention, the related substance is introduced into the first tubular member via the funnel-shaped guide member provided in the reactor, thereby reducing the size of the heater. Therefore, it is possible to realize a high-temperature valve device having a compact configuration, which can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

  According to the configuration of the eleventh aspect of the present invention, even when the related substance contains zinc and zinc chloride that are highly corrosive to metals and the like, by applying the high temperature valve device having the above configuration, This can contribute to the production of silicon with reduced contamination of related substances during the production of silicon.

It is a typical longitudinal cross-sectional view of the silicon manufacturing apparatus used in the 1st Embodiment of this invention. It is a typical longitudinal section of the upper valve device applied to the silicon manufacture device in this embodiment. FIG. 3A is a schematic longitudinal sectional view of a modified upper valve device applied to the silicon manufacturing apparatus in the present embodiment, and FIG. 3B is a cross-sectional view taken along the line AA in FIG. FIG. It is a typical longitudinal cross-sectional view of the silicon manufacturing apparatus used in the 2nd Embodiment of this invention.

  The high temperature valve device according to each embodiment of the present invention will be described below in detail with reference to the drawings as an example when applied to a silicon manufacturing apparatus. In the figure, the x-axis, y-axis, and z-axis form a three-axis orthogonal coordinate system, the z-axis indicates the vertical direction that is the vertical direction, and the negative direction of the z-axis is downward and downstream. To do.

(First embodiment)
First, the high temperature valve device according to the first embodiment of the present invention will be described in detail with reference to FIGS.

  FIG. 1 is a schematic longitudinal sectional view of a silicon manufacturing apparatus used in this embodiment. FIG. 2 is a schematic longitudinal sectional view of the upper valve device applied to the silicon manufacturing apparatus in the present embodiment.

  As shown in FIGS. 1 and 2, the silicon manufacturing apparatus 1 is typically cylindrical and coaxial with the central axis C parallel to the z axis and extends in the vertical direction. The reactor 10 in which the reduction reaction reduced with zinc occurs. The reactor 10 is typically made of quartz, and an insertion hole 10a is formed in the vertical wall thereof. Further, the upper end of the reactor 10 is typically made of quartz and is closed by a disc-shaped upper lid 12 fixed to the reactor 10, and the lower end of the reactor 10 is typically fixed to quartz. It is made of a disc-shaped bottom plate 30 and is closed.

  Here, in the silicon production apparatus 1, the reactor 10 is a vertical reactor having a dimension in which the length L between the mating surface to the upper lid 12 and the lower surface of the bottom plate 30 is longer than the diameter D thereof. Inside the reactor 10, zinc gas is supplied above (upstream side) from the silicon tetrachloride gas, and while appropriately setting the temperature of the reactor 10, a reduction region is generated and a deposition region in which silicon is deposited is formed. The silicon tetrachloride gas is defined below (downstream side) from the portion to which silicon tetrachloride gas is supplied, and silicon can be recovered from below (more downstream side) of the reactor 10.

  Specifically, the upper lid 12 that closes the upper open end of the reactor 10 is provided with a plurality of insertion holes 12a coaxially with the central axis C in the central region, and so as to surround the insertion holes 12a adjacent to each other. An insertion hole 12b and a plurality of insertion holes 12c are formed.

  A single zinc gas supply pipe 18, typically made of quartz, is inserted into and fixed to one insertion hole 12 a in communication with a zinc gas supply source (not shown). The zinc gas supply pipe 18 penetrates into the reactor 10, extends vertically downward coaxially with the central axis C, and opens in the direction perpendicular to the central axis C at the lower end of the vertical wall. While having the zinc gas supply port 18a to be operated, the vertical tip thereof is closed. In addition, as a zinc gas supply source, the structure which introduce | transduces a zinc wire into the part extended in the perpendicular direction of this zinc gas supply pipe | tube 18, and heats and evaporates a zinc wire more than a boiling point with the heater mentioned later for details May be employed, or an independent zinc gas supply device may be employed. If necessary, the zinc gas supply pipe 18 can be mixed with an inert gas from an inert gas source (not shown).

  It is preferable that a plurality of zinc gas supply ports 18a of the zinc gas supply pipe 18 are provided. Typically, three zinc gas supply ports 18a are opened at the lower end of the vertical wall at equal intervals of 120 ° with respect to the central axis C. Is preferred. This is because the zinc gas is discharged into the reactor 10 in the horizontal direction and more reliably diffuses evenly, so that the mixing of the zinc gas and the silicon tetrachloride gas can be performed better. Of course, when zinc gas and silicon tetrachloride gas are mixed well, only one zinc gas supply port 18a of the zinc gas supply pipe 18 may be provided, or the vertical direction of the zinc gas supply pipe 18 may be increased. The tip in the direction may be opened.

The plurality of insertion holes 12 b are typically equidistant from the central axis C and 1 in the circumferential direction of the upper lid 12.
Three are provided at equal intervals of 20 °. In each of the insertion holes 12b, an inert gas supply pipe 14 that is typically made of quartz is inserted into and fixed to an inert gas supply source (not shown), and the inert gas supply pipe is fixed. 14 has an inert gas supply port 14a which penetrates into the reactor 10 and extends vertically downward in parallel to the central axis C and is an opening opened at the lower end thereof. Further, inside the inert gas supply pipe 14, a single silicon tetrachloride gas supply pipe 16 typically made of quartz is provided in contact with a silicon tetrachloride gas supply source (not shown). The silicon tetrachloride gas supply pipe 16 penetrates into the reactor 10 and extends vertically downward in parallel with the central axis C. The silicon tetrachloride gas supply pipe 16 has a silicon tetrachloride gas supply port 16a opened at a lower end portion of the vertical wall in a direction orthogonal to the central axis C, while its vertical end is closed. Yes. In addition, the silicon tetrachloride gas supply pipe | tube 16 can be connected to the inert gas supply source which abbreviate | omits illustration as needed.

  The silicon tetrachloride gas supply port 16a of the silicon tetrachloride gas supply pipe 16 only needs to be opened at an arbitrary position and an arbitrary number at the lower end of the vertical wall. This is because it is sufficient that the silicon tetrachloride gas is discharged in the horizontal direction from the viewpoint of the mixing of zinc gas and silicon tetrachloride gas.

  The plurality of insertion holes 12c are typically provided at equal distances from the central axis C, at equal intervals of 120 ° in the circumferential direction of the upper lid 12, and so as to sandwich the corresponding insertion holes 12b. The insertion tube 24a of the peeling mechanism 24, which will be described in detail later, is inserted and fixed in each insertion hole 12c.

  In this way, one zinc gas supply pipe 18 is inserted into the center of the upper lid 12 to extend the inside of the reactor 10, and the silicon tetrachloride gas supply included in the plurality of inert gas supply pipes 14 is surrounded by the zinc gas supply pipe 18. The reason for adopting the configuration in which the pipe 16 is disposed is that the zinc gas having a boiling point of 910 ° C. needs to be introduced into the reactor 10 in a state of being heated to a higher temperature than the silicon tetrachloride gas having a boiling point of 59 ° C. Therefore, although the diameters of the reactor 10 and the upper lid 12 tend to be slightly larger, the zinc gas maintained at a relatively high temperature can be reliably ensured in the radial direction in the reactor 10 while making the configuration of the entire apparatus more compact. This is because the convenience of introducing the silicon tetrachloride gas in a distributed manner around the central portion is considered. If the diameter of the reactor 10 or the upper lid 12 can be further increased, a plurality of zinc gas supply pipes 18 may be provided in the central region of the upper lid 12.

  Here, the inert gas supply port 14 a opens to the inside of the reactor 10 at a position of a length L1 from the mating surface to the upper lid 12 of the reactor 10. Further, the silicon tetrachloride gas supply port 16a opens to the inside of the reactor 10 at a position of a length L2 (L2> L1) from the mating surface to the upper lid 12 of the reactor 10. Further, the zinc gas supply port 18a opens to the inside of the reactor 10 at a position of a length L3 (L3 <L2) from the mating surface to the upper lid 12 of the reactor 10. That is, the opening position (lower end position) of the inert gas supply port 14a is above the opening position (typically the center position) of the silicon tetrachloride gas supply port 16a. Moreover, the opening position (typically the central position) of the zinc gas supply port 18a is above the opening position of the silicon tetrachloride gas supply port 16a, and below the opening position of the inert gas supply port 14a. (L1 <L3 <L2).

  An exhaust pipe 20 typically made of quartz is inserted into an insertion hole 10 a provided in the vertical wall of the reactor 10 in communication with an exhaust gas processing device (not shown). The exhaust pipe 20 is preferably welded through the insertion hole 10a of the reactor 10 and configured integrally with the reactor 10 in terms of durability. Further, the end of the exhaust pipe 20 on the side of the reactor 10 has an exhaust inlet 20 a that opens in the reactor 10.

Further, the vertical wall of the reactor 10 is surrounded by the upper heater 22 from the outside. The upper heater 22 is a typically cylindrical electric furnace that is coaxial with the central axis C, and sequentially connects the first heating unit 22a, the second heating unit 22b, and the third heating unit 22c downward in the vertical direction. The third heating portion 22c is provided with a through hole 22d through which the exhaust pipe 20 passes.

  Furthermore, a typically cylindrical inner tube 26 extending coaxially with the central axis C is inserted into the reactor 10 along its inner wall. The inner tube 26 is typically made of quartz and is detachable from the reactor 10, and the inner wall surface of the inner tube 26 becomes a precipitation region S in which polycrystalline silicon is deposited.

  Specifically, the upper end 26a of the inner pipe 26 is an open end and is at a position of a length L4 from the mating surface to the upper lid 12 of the reactor 10, and the inert gas supply port of the inert gas supply pipe 14 While the opening position of 14a is above the upper end 26a of the inner pipe 26, it is above the opening positions of the silicon tetrachloride gas supply port 16a and the silicon tetrachloride gas supply port 16a of the silicon tetrachloride gas supply pipe 16. Each opening position of the zinc gas supply port 18a of the zinc gas supply pipe 18 is located below the upper end 26a of the inner pipe 26 (L1 <L4 <L3 <L2).

  Thus, the opening position of the silicon tetrachloride gas supply port 16a of the silicon tetrachloride gas supply pipe 16 and the opening position of the zinc gas supply port 18a of the zinc gas supply pipe 18 are lower than the upper end 26a of the inner pipe 26. The reason for this is that by adopting a configuration in which the zinc gas supply pipe 18 is inserted into the center of the upper lid 12 and the inside of the reactor 10 is extended, it is simple without providing an insertion hole in the vertical wall of the inner pipe 26. In addition to the fact that the zinc gas supply port 18a can be disposed below in a simple configuration, the zinc gas is also discharged inside the inner pipe 26 in addition to the silicon tetrachloride gas, so that the reactor 10 The deposition region S can be reliably defined on the inner wall surface of the inner tube 26 by reliably suppressing the phenomenon that the gas diffuses and penetrates unnecessarily in the gap between the vertical inner wall of the inner tube 26 and the outer wall of the inner tube 26. This is because of this.

  Further, since the lower end of the inner pipe 26 is connected to the bottom plate 30 and extends downward beyond the exhaust pipe 20, the inner pipe 26 of the reactor 10 is not unnecessarily covered with the exhaust inlet 20 a of the exhaust pipe 20. An insertion hole 26b is provided at a position corresponding to the insertion hole 10a. That is, the exhaust pipe 20 is fixed by being inserted into the insertion hole 10 a provided in the vertical wall of the reactor 10 and the insertion hole 26 b provided in the vertical wall of the inner pipe 26.

  Further, in the inner pipe 26, it extends below the insertion hole 26b corresponding to the exhaust introduction port 20a, extends between the inner wall surface of the inner pipe 26 and the upper surface of the bottom plate 30, and decreases in diameter downward. A funnel-shaped guide member 32 fixed to them is arranged. The inner wall surface at the lower end portion of the guide member 32 is continuous with a through hole 30 a formed in the bottom plate 30. By providing the guide member 32, it becomes possible to smoothly guide the polycrystalline silicon, which is peeled off by the peeling mechanism 24 and falls by its own weight, to the upper valve device 40 disposed below, which will be described in detail later. The size of the lower heater 100 of the upper valve device 40 can be reduced without unnecessarily increasing.

  Moreover, since the inner pipe 26 is heated and maintained at a high temperature such as a temperature of 1000 ° C. or more and 1100 ° C. or less by the second heating unit 22b and the third heating unit 22c in the upper heater 22, the outer wall surface thereof is maintained. Considering that there is a possibility that they may stick to each other and cannot be removed if they are in contact with the inner wall surface of the reactor 10, they are juxtaposed with respect to the reactor 10 via a predetermined gap. In order to stably maintain such a gap, it is typically preferable to install a quartz spacer.

More specifically, in the upper heater 22, the first heating unit 22a is a heating unit that can be heated and maintained so as to exhibit a temperature exceeding the deposition temperature at which silicon is deposited (eg, 1200 ° C.), and is an inert gas. Inert gas supply pipe 14 having supply port 14a, silicon tetrachloride gas supply port 1
Surrounding the vertical wall of the reactor 10 in which the silicon tetrachloride gas supply pipe 16 having 6a and the zinc gas supply pipe 18 having the zinc gas supply port 18a are arranged, the corresponding vertical wall of the inner pipe 26 and the inside thereof, This region is heated and maintained at a temperature exceeding the deposition temperature at which silicon is deposited.

  Here, as a range of the deposition temperature at which silicon is deposited, a range of 950 ° C. to 1100 ° C. can be evaluated as a suitable temperature range. This is because when the vertical wall of the reactor 10, the vertical wall of the inner tube 26, and the temperature inside thereof are lower than 950 ° C., the reaction rate of the reduction reaction in which silicon tetrachloride is reduced with zinc is slowed down. Thus, when the vertical wall of the reactor 10, the vertical wall of the inner tube 26, and the temperature inside thereof exceed 1100 ° C., it is more stable that silicon exists as a compound gas of silicon tetrachloride than when it exists as a solid. This is because it is considered that such a reduction reaction itself does not occur. Further, since the boiling point of zinc is 910 ° C., the range of the deposition temperature at which such silicon is deposited is a temperature range exceeding the boiling point of zinc.

  Further, the second heating unit 22b and the third heating unit 22c provided continuously below the second heating unit 22b are heating units that can be heated and maintained so as to exhibit a temperature within the silicon deposition temperature range, and are inactive. The vertical wall of the reactor 10 in which the gas supply pipe 14, the silicon tetrachloride gas supply pipe 16 and the zinc gas supply pipe 18 are not disposed, the vertical wall of the inner pipe 26 corresponding thereto, and the inside thereof are continuously covered up and down. The region is heated and maintained at the deposition temperature at which silicon is deposited.

  Here, the second heating unit 22b is below the portion heated by the first heating unit 22a, and the vertical wall of the reactor 10 at a temperature (for example, 1100 ° C.) within the range of the deposition temperature at which silicon is deposited, It is a heating unit capable of heating the vertical wall of the inner tube 26 and the inside thereof. In addition, the third heating unit 22c has a temperature lower than the heating temperature of the second heating unit 22b (for example, 1000) within the range of the deposition temperature at which silicon is deposited below the portion heated by the second heating unit 22b. It is a heating section capable of heating the vertical wall of the reactor 10, the vertical wall of the inner tube 26, and the inside thereof at a temperature of ° C.

  The second heating unit 22b exhibits an intermediate heating temperature that connects the heating temperature of the first heating unit 22a and the heating temperature of the third heating unit 22c, but may be omitted as necessary. In other words, the vertical wall of the reactor 10 and the corresponding inner pipe 26 in the portion where the silicon tetrachloride gas supply pipe 16 having the silicon tetrachloride gas supply opening 16a and the zinc gas supply pipe 18 having the zinc gas supply opening 18a are arranged. A reactor in a portion where the silicon tetrachloride gas supply pipe 16 and the zinc gas supply pipe 18 are not arranged vertically below the first heating section 22a that heats the vertical wall and the inside thereof at a temperature exceeding the deposition temperature at which silicon is deposited. What is necessary is just to provide the heating part which heats the vertical wall of 10 vertical walls, the corresponding vertical wall of the inner pipe | tube 26, and the inside in the precipitation temperature range which silicon precipitates. In addition, the 2nd heating part 22b also has a function which adjusts so that the difference of the heating temperature of the 1st heating part 22a and the heating temperature of the 3rd heating part 22c may not become excessive, The temperature of the vertical wall etc. of the inner tube | pipe 26, etc. An excessive change can be suppressed.

  In addition, all of the heating temperature of the 1st heating part 22a in the upper heater 22, the 2nd heating part 22b, and the 3rd heating part 22c all exceed 910 degreeC which is the boiling point of zinc.

  The peeling mechanism 24 is a mechanism for peeling the polycrystalline silicon deposited on the precipitation region S on the inner wall surface of the inner tube 26 attached to the reactor 10 and dropping it downward under its own weight. The introduction pipe 24a is inserted and fixed to 12c.

More specifically, the peeling mechanism 24 includes a rod member 24b typically made of quartz that is inserted through an introduction tube 24a fixed to each insertion hole 12c so as to be vertically movable and extends in parallel with the central axis C. . The rod member 24b penetrates into the reactor 10 and interferes with the polycrystalline silicon layer deposited on the deposition region S on the inner wall surface of the inner tube 26, but it interferes unnecessarily with the inner wall surface of the inner tube 26 itself. In order to prevent this, the inner wall 26 of the inner tube 26 extends in parallel and faces the inner wall surface of the inner tube 26 while being separated by a predetermined distance. The shape of the rod member 24b is typically a columnar shape when the inner tube 26 is cylindrical, and is typically a prismatic shape when the inner tube 26 is a rectangular tube.

  Further, the peeling mechanism 24 is interposed between the upper end portion of the introduction pipe 24a and the flange portion, which is the upper end portion of the rod member 24b, and seals an internal region through which the rod member 24b is inserted and has a predetermined spring constant. It has a bellows-like telescopic tube 24c that is an elastic member, a weight 24d that is placed on a flange that is the upper end of the rod member 24b, and an actuator 24e that communicates with the weight 24d. In the initial state, the telescopic tube 24c may be set in a compressed state in which the actuator 24e is engaged with the weight 24d at the lowest position so as to receive a load from the weight 24d and contract by a predetermined length. The non-compressed state may be set so as to exhibit a substantially natural length so that the load of the weight 24d is not substantially received by locking the 24d at the uppermost position. In addition, when the lower end part of the expansion / contraction tube 24c is brought into direct contact with the upper surface of the upper lid 12, the introduction tube 24a can be omitted.

  In the peeling mechanism 24, when the telescopic tube 24c is set in the compressed state in the initial state, the rod member 24b is correspondingly at the lowest position, but the actuator 24e is operated to engage the weight 24d. The rod member 24b is moved upward by the pulling force of the actuator 24e while receiving the extension force of the extension tube 24c by lifting the extension tube 24c in a compressed state by releasing the stop and pulling it upward. Can move up to. When the bar member 24b moves to the uppermost position, the weight 24d is locked by the actuator 24e, and the bar member 24b is maintained at the uppermost position. Of course, when the rod member 24b is moved to the uppermost position, the actuator 24e may keep the weight 24d not locked when necessary. In such a case, the telescopic tube 24c is attached to the weight 24d. By contracting in response to the load, the bar member 24b can move downward to the lowest position, and then the bar member 24b repeats such an up / down movement as necessary. Is possible.

  On the other hand, when the telescopic tube 24c is set to an uncompressed state in the initial state, the rod member 24b is correspondingly at the uppermost position, but the actuator 24e is operated to lock the weight 24d. By unwinding and applying the load of the weight 24d to the telescopic tube 24c and contracting, the rod member 24b moves downward to the lowest position by the load of the weight 24d while receiving the compression reaction force of the telescopic tube 24c. be able to. When the bar member 24b moves to the lowest position, the weight 24d is locked by the actuator 24e, and the bar member 24b is maintained at the lowest position. Of course, when the rod member 24b moves to the lowest position, the actuator 24e may pull up the weight 24d without being locked, if necessary. In such a case, the telescopic tube 24c is pulled up by the weight 24d. The rod member 24b can move upward and move to the uppermost position by being stretched without receiving the load, and thereafter, the rod member 24b performs such an up / down movement operation as necessary. It is possible to repeat.

  Here, in the case where polycrystalline silicon is deposited in the precipitation region S on the inner wall surface of the inner tube 26, the bar member 24b is opposed to the lower tip and the precipitation region S by performing such vertical movement. The side surface mechanically hits the polycrystalline silicon typically formed of acicular crystals deposited in the precipitation region S, and the impact causes the acicular polycrystalline silicon to be removed from the precipitation region S, that is, from the inner wall surface of the inner tube 26. It can be folded and peeled and dropped by its own weight below the reactor 10.

That is, since the bar member 24b is required to peel the polycrystalline silicon deposited in the silicon deposition region S and move it down below the reactor 10 by moving it up and down, The moving range in the vertical direction must be such that at least the lower tip can take a position between a position vertically above and a position vertically below the upper end of the silicon deposition region S. It is. In order to peel the polycrystalline silicon deposited in the silicon deposition region S more reliably, the lower end of the rod member 24b is moved from the lower end of the silicon deposition region S as the vertical movement range of the rod member 24b. It is more preferable to secure a moving range that reaches a position vertically below.

  In addition, as an apparatus for moving the bar member 24b up and down, an apparatus including the telescopic tube 24c, the weight 24d, and the actuator 24e is shown. However, the present invention is not limited to this and is more expensive. A device such as an air cylinder may be used.

  Furthermore, since the polycrystalline silicon deposited in the precipitation region S on the inner wall surface of the inner tube 26 is peeled off and falls downward due to its own weight, the bottom plate 30 fixed to the lower end of the reactor 10 The upper valve device 40, the communication pipe 102, the lower valve device 104, and the silicon recovery tank 106 are sequentially connected to the lower side.

  Specifically, the upper valve device 40 is a high-temperature valve device, which is related to the formation of polycrystalline silicon in the reactor 10 and is in the form of a melt or solid that falls downward through the through hole 30a of the bottom plate 30. The related substances are prevented from diffusing from the reactor 10 toward the silicon recovery tank 106 and being sent unnecessarily. Typically, the outer tube 50 made of quartz, And an inner pipe 60 made of quartz, and a lower heater 100 arranged around the outer pipe 50.

  Here, as a related substance relevant to the production | generation of the polycrystalline silicon in the reactor 10, the raw material for reaction is mentioned in addition to reaction by-products other than the silicon | silicone which is the objective of manufacture. For example, in the case where silicon is produced by a reduction reaction between silicon tetrachloride and zinc, such related substances include, in addition to zinc chloride, which is a reaction by-product other than silicon, which is the object of production, none of them. Silicon tetrachloride and zinc which are raw materials for the reaction are included.

  Specifically, the outer pipe 50 is coaxial with the central axis C and extends in the vertical direction in order, typically a cylindrical upper vertical outer pipe 52 and a lower vertical outer pipe 54, and a center orthogonal to the central axis C. A transverse outer tube 56 that is typically cylindrical and extends in the direction of the axis CL.

  The upper vertical outer tube 52 has an upper end flange 52a and a lower end 52b. The upper end flange 52a is attached to the bottom plate 30 from below, and the inner space of the upper vertical outer tube 52 is formed in the bottom plate 30. It communicates with the internal space of the reactor 10 through the through hole 30a. The lower vertical outer pipe 54 has a lower end flange 54a and an upper end 54b. The lower end flange 54a is attached with the connecting pipe 102 from below, and the inner space of the lower vertical outer pipe 54 is an upper vertical outer pipe. It is possible to communicate with the internal space 52.

  The lateral outer tube 56 is opposed to each other through the flange 56a provided at one end thereof, the enlarged diameter portion 56b provided at the other end facing the one end, and the wall portion of the lateral outer tube 56 therebetween. It has a pair of insertion holes 56c and 56d formed in. A lower end 52b of the upper vertical outer tube 52 is inserted and welded into the upper insertion hole 56c, while an upper end 54b of the lower vertical outer tube 54 is inserted and welded into the lower insertion hole 56d. Instead of forming the pair of insertion holes 56c and 56d in the horizontal outer tube 56 in this way, the upper vertical outer tube 52 and the lower vertical outer tube 54 are formed as one vertical outer tube, and the two horizontal outer tubes 56 are formed. It is also possible to divide and provide a pair of insertion holes for one vertical outer pipe, and insert and weld the ends of the two horizontal outer pipes correspondingly.

  The inner tube 60 is rotatable about the central axis CL as a rotation axis, and is arranged in the horizontal outer tube 56 so as not to be exposed in the upper vertical outer tube 52 and the lower vertical outer tube 54, and is typically a cylinder. An inner pipe main body portion 62, and a valve 64 that is connected to the inner pipe main body portion 62 and that is disposed so as to be exposed in the upper vertical outer pipe 52 and the lower vertical outer pipe 54 in the lateral outer pipe 56, and Have.

  The inner pipe main body 62 has a communication hole 62b that allows the internal space of the inner pipe main body 62 to communicate with the outside at the other end 62a that closes the inner pipe main body 62 on the side opposite to the valve 64. Further, a motor (not shown) is connected to the other end portion 62a, and the inner tube 60 is rotatable about the central axis CL as a rotation axis by driving and controlling the motor.

  The valve 64 corresponds to the first wall portion 64a that is continuous with the inner tube main body portion 62 and closes the inner tube main body portion 62 on the opposite side of the other end portion 62a, and the inner space on the flange 56a side of the lateral outer tube 56. It has the 2nd wall part 64b arrange | positioned, and the valve | bulb main-body part 64c of the flat plate shape typically extended between the 1st wall part 64a and the 2nd wall part 64b. The valve 64 is rotated about the central axis CL as a rotation axis by rotating the inner tube 60, that is, the inner tube main body 62, about the central axis CL.

  That is, when the valve main body 64c is in a horizontal state parallel to the xy plane, the upper vertical outer pipe 52 and the lower vertical outer pipe 54 are closed to make their internal spaces substantially in a non-communication state. The polycrystalline silicon that has been generated in step S <b> 2 and dropped by the peeling mechanism 24 and dropped through the through hole 30 a of the bottom plate 30 can be deposited on the valve body 64 c. On the other hand, when the valve main body 64c is rotated from the horizontal state, the upper vertical outer pipe 52 and the lower vertical outer pipe 54 are correspondingly opened so that the internal spaces thereof are in communication and deposited on the valve main body 64c. The polycrystalline silicon is allowed to fall further toward the communication tube 102 and the silicon recovery tank 106 below.

  Further, the inner tube 60 having the inner tube main body 62 and the valve 64 can be rotated about the central axis CL as a rotation axis without contacting the upper vertical outer tube 52, the lower vertical outer tube 54 and the horizontal outer tube 56. The outer surface of the inner tube main body 62, the outer end of the first wall 64a of the valve 64 and the outer end of the second wall 64b of the valve 64, and the correspondence of the lateral outer tube 56 A gap portion exists between the inner surface portion and the inner surface portion.

  Here, a gland seal 70 is interposed between the inner surface portion of the enlarged diameter portion 56 b of the lateral outer tube 56 and the corresponding outer surface portion of the inner tube main body portion 62. Such a ground seal 70 maintains a gap set between the outer surface portion of the inner tube main body portion 62, the outer end portion of the first wall portion 64 a of the valve 64, and the inner surface portion of the lateral outer tube 56. The inner tube 60 is rotatable about the central axis CL as a rotation axis while sealing the end of the portion. Further, the gland seal 70 is prevented from coming off by a pressing member 72 attached to the enlarged diameter portion 56 b of the lateral outer tube 56.

  Further, an inert gas supply pipe 74 is inserted into an insertion hole 56c formed through the wall of the lateral outer pipe 56, and an inert gas supply source (not shown) is connected to the inner pipe main body 62. An inert gas can be freely supplied to a gap portion set between the outer surface portion and the outer end portion of the first wall portion 64 a of the valve 64 and the corresponding inner surface portion of the lateral outer tube 56.

  On the other hand, a side plate 76 made of quartz is typically fixed to the flange 56a of the lateral outer tube 56, and the end of the inner space of the lateral outer tube 56 is closed on the side opposite to the enlarged diameter portion 56b. An inert gas supply pipe 78 is inserted into the insertion hole 76 a formed through the side plate 76, and the inner space of the lateral outer pipe 56 and the first of the valve 64 are supplied from an inert gas supply source (not shown). The inert gas can be supplied to a gap portion set between the outer end portion of the second wall portion 64b and the corresponding inner surface portion of the lateral outer tube 56.

As described above, the inert gas is supplied from the inert gas supply source to the inert gas supply pipes 74 and 78 by the outer surface portion of the inner tube main body portion 62 and the outer end portion of the first wall portion 64 a of the valve 64. Between the inner wall portion of the lateral outer pipe 56 and the inner wall portion of the lateral outer pipe 56 corresponding to the outer end portion of the second wall 64b of the valve 64. An inert gas having a predetermined pressure is supplied to the gap portion, and polycrystalline silicon generated in the reactor 10 and related substances are unnecessarily intruded into the gap portion while dropping downward. This is to prevent the valve 64 from adhering to the valve 64 due to the solidified related substance.

  Further, the inert gas supply source and the inert gas supply pipes 74 and 78 constitute an inert gas supply mechanism, and the inert gas supply source is provided separately for the inert gas supply pipes 74 and 78. Or may be provided in common.

  Further, in the lower heater 100, the related substance related to the generation of polycrystalline silicon in the reactor 10 is in a molten or solid phase state, passes through the through hole 30 a of the bottom plate 30 and the upper vertical outer tube 52, In order to prevent unnecessary diffusion from the reactor 10 toward the silicon recovery tank 106 and to send it, a predetermined heating region is heated in a predetermined temperature range to maintain the related substance in a gaseous state. Is provided.

  Specifically, the heating area heated by the lower heater 100 is an area including the upper vertical outer pipe 52 and the valve 64 extending from the bottom plate 30 attached to the reactor 10 to the valve 64. The lower heater 100 surrounds the upper vertical outer tube 52 and the valve main body 64c so that the heating region can be heated above the boiling point of the related substance related to the generation of polycrystalline silicon in the reactor 10, and The outer pipe 52, the lower vertical outer pipe 54, and the lateral outer pipe 56 are disposed around a part of the circumference. Further, since the related substance related to the generation of polycrystalline silicon in the reactor 10 passes through the internal space of the guide member 32 in the reactor 10 and reaches the upper vertical outer tube 52, the lower heater 100 is It arrange | positions under the 3rd heating part 22c continuously from the 3rd heating part 22c of the upper heater 22 so that the area | region where a related substance may not be heated between the guide member 32 and the upper vertical outer pipe | tube 52 may arise. . The lower heater 100 is appropriately formed with a through hole or the like in order to prevent mechanical interference with the upper vertical outer pipe 52, the lower vertical outer pipe 54, the horizontal outer pipe 56, and the inert gas supply pipe 78. .

  Further, the range of the heating temperature of the lower heater 100 is such that related substances related to the generation of polycrystalline silicon in the reactor 10 diffuse and flow into the upper vertical outer pipe 52 through the through holes 30a of the bottom plate 30. In addition, it is necessary to set the temperature range in which the related substance is vaporized without being in a molten or solid phase state, and does not unnecessarily melt the generated silicon.

  That is, the range of the heating temperature of the lower heater 100 needs to be set to a range not lower than the melting point of silicon and not lower than the highest boiling point among the boiling points of the related substances. For example, when silicon is produced by the reduction reaction of silicon tetrachloride and zinc, the boiling point of silicon tetrachloride is 59 ° C., the boiling point of zinc chloride is 732 ° C., and the boiling point of zinc is 910 ° C. The heating temperature of 100 may be set in the range of 910 ° C. or higher which is the highest boiling point temperature and 1410 ° C. or lower which is the melting point of silicon. In reality, the heating temperature of the lower heater 100 is 950 ° C., considering that it is sufficient to uniformly and uniformly heat the heating area including the upper vertical outer pipe 52 and the valve 64 from the bottom plate 30 to the valve 64. Any degree is acceptable.

  Further, the gland seal 70 interposed between the inner surface portion of the enlarged diameter portion 56b of the lateral outer tube 56 and the outer surface portion of the corresponding inner tube main body portion 62 has an outer surface portion when the inner tube main body portion 62 rotates. Are slidably in contact with the outer surface of the ground seal 70, and are typically materials having good sliding properties and heat resistance such as PTFE (polytetrafluoroethylene) and ETFE (ethylene tetrafluoroethylene). Although it is made of fluororesin, its heat resistance is limited. Therefore, the gland seal 70 is disposed apart from the range of the heating area of the lower heater 100 and is placed in a temperature atmosphere equal to or lower than the normal heat resistance temperature.

  A communication pipe 102 is attached to the lower end flange 54 a of the lower vertical outer pipe 54 in the upper valve device 40 from below, and the communication pipe 102 communicates with the inside of the reactor 10 through the upper valve device 40. Further, the lower valve device 104 is connected to the communication pipe 102.

  The lower valve device 104 includes a valve 104 a that can shut off the internal environment and the external environment of the reactor 10 at a position closer to the silicon recovery tank 106. In a state where the valve 104a is closed so as to block communication between the upper valve device 40 and the silicon recovery tank 106, when the valve 64 of the upper valve device 40 is rotated and opened, it is deposited on the valve 64 by its own weight. The falling polycrystalline silicon can be deposited on the valve 104a. On the other hand, when the valve 104a is opened so as to communicate with the upper valve device 40 and the silicon recovery tank 106, the polycrystalline silicon deposited on the valve 104a can be recovered by dropping into the silicon recovery tank 106 by its own weight. .

  Further, the silicon recovery tank 106 is installed in a normal temperature atmosphere outside the heating region of the upper heater 22 and outside the heating region of the lower heater 100, and is detachable from the silicon manufacturing apparatus 1.

  Next, a silicon manufacturing method for manufacturing polycrystalline silicon using the silicon manufacturing apparatus 1 having the above configuration will be described in detail. Note that a series of steps of the silicon manufacturing method may be automatically controlled by a controller having various databases or the like while referring to detection data from various sensors, or may be partly or wholly performed manually.

  First, the valve 64 of the upper valve device 40 and the valve 104a of the lower valve device 104 are closed so that the inside and outside of the reactor 10 are shut off from the inert gas supply port 14a. An active gas is supplied for a predetermined time to prepare a reaction atmosphere inside the reactor 10. At this time, an inert gas may be supplied for a predetermined time from the silicon tetrachloride gas supply port 16a and the zinc gas supply port 18a as necessary.

  Next, an inert gas supply pipe 14 having an inert gas supply port 14a, a silicon tetrachloride gas supply pipe 16 having a silicon tetrachloride gas supply port 16a, and zinc gas supply by the first heating unit 22a in the upper heater 22 The vertical wall of the reactor 10 in which the zinc gas supply pipe 18 having the port 18a is arranged, the corresponding vertical wall of the inner pipe 26 and the inside thereof are heated, and this portion is heated to a temperature exceeding the silicon deposition temperature. maintain. At the same time, the vertical wall of the reactor 10 in which the inert gas supply pipe 14, the silicon tetrachloride gas supply pipe 16, and the zinc gas supply pipe 18 are not arranged by the second heating section 22b and the third heating section 22c in the upper heater 22 is provided. The corresponding vertical wall of the inner tube 26 and the inside thereof are heated, and this portion is heated and maintained within the silicon deposition temperature range.

  At the same time, the lower heater 100 causes the heating zone including the upper outer pipe 52 and the valve 64 from the bottom plate 30 attached to the reactor 10 to the valve 64 to be used as a related substance related to the production of polycrystalline silicon in the reactor 10. It is heated and maintained in a temperature range not lower than the melting point of silicon and not lower than the highest boiling point among the boiling points exhibited by.

Next, the reduction reaction step is performed while maintaining such temperature conditions. Specifically, silicon tetrachloride gas is supplied into the reactor 10 from the silicon tetrachloride gas supply port 16a, and zinc gas is supplied from the zinc gas supply port 18a. At this time, the inert gas supply pipes 74 and 78 are set between the outer surface portion of the inner tube main body portion 62 and the outer end portion of the first wall portion 64a of the valve 64 and the inner surface portion of the corresponding lateral outer tube 56. An inert gas is supplied correspondingly to the gap portion formed between the outer end portion of the second wall portion 64b of the valve 64 and the corresponding inner surface portion of the lateral outer tube 56. . At this time, an inert gas may be supplied from the inert gas supply port 14a as necessary.

  Then, a reduction reaction in which silicon tetrachloride is reduced with zinc can occur inside the reactor 10. However, since the silicon tetrachloride gas is a relatively heavy gas whose specific gravity is about 2.6 times the specific gravity of the zinc gas, the zinc gas above the opening position of the silicon tetrachloride gas supply port 16a. It cannot substantially diffuse up to the supply port 18a, and a reduction reaction occurs in the vicinity of the silicon tetrachloride gas supply port 16a inside the reactor 10 or in a region below it, so that solid silicon and zinc chloride gas are generated. It will be.

  Further, here, the vertical wall of the reactor 10 where the inert gas supply pipe 14, the silicon tetrachloride gas supply pipe 16 and the zinc gas supply pipe 18 are not arranged, the corresponding vertical wall of the inner pipe 26 and the inside thereof are Since the second heating unit 22b and the third heating unit 22c are heated and maintained so as to exhibit a temperature in the silicon deposition temperature range, the silicon generated by the reduction reaction is below the vertical wall of the inner tube 26, That is, it precipitates as a needle-like crystal in the precipitation region S, which is a region below the silicon tetrachloride gas supply port 16a and above the exhaust introduction port 20a on the inner wall surface of the inner pipe 26. At this time, silicon is not deposited in the silicon tetrachloride gas supply port 16a and the zinc gas supply port 18a, and the supply port is not blocked by silicon.

  Further, in this manner, in the precipitation region S in the lower portion of the inner wall surface of the inner tube 26, acicular silicon is deposited sequentially, and silicon grows using the deposited silicon as a seed crystal. A sufficient thickness of polycrystalline silicon will be deposited. Here, such a precipitation process and a crystal growth process related thereto are referred to as precipitation.

  Next, after the reduction reaction is continued for a predetermined time, if polycrystalline silicon having a sufficient thickness is deposited in the precipitation region S in the lower portion of the inner wall surface of the inner tube 26, Stop supplying zinc gas. Then, with the inert gas supplied from the inert gas supply port 14a of the inert gas supply pipe 14 to the inside of the reactor 10, the atmosphere inside the reactor 10 is replaced with the inert gas.

  Next, when the rod member 24b is moved up and down correspondingly by actuating the actuator 24e of the peeling mechanism 24 and releasing or locking the weight 24d to extend or compress the telescopic tube 24c, the tip and side surfaces thereof are The polycrystalline silicon deposited on the precipitation region S on the inner wall surface of the tube 26 is mechanically peeled off from the inner wall surface of the inner tube 26 by breaking the needle-like polycrystalline silicon by the impact, and the peeled material is moved downward by its own weight. Fall into. At this time, since the valve 64 of the upper valve device 40 is closed, the falling silicon is deposited on the valve 64.

  At this time, the heating region including the upper vertical outer pipe 52 and the valve 64 extending from the bottom plate 30 attached to the reactor 10 to the valve 64 by the lower heater 100 is related to the production related to the production of polycrystalline silicon in the reactor 10. Since the substance is heated and maintained in a temperature range higher than the highest boiling point among the boiling points exhibited by the substance and lower than the melting point of silicon, the valve 64 can be used in a melted or solidified state. The deposition on top is reduced.

Further, the inert gas supply pipes 74 and 78 are set between the outer surface portion of the inner tube main body portion 62 and the outer end portion of the first wall portion 64a of the valve 64 and the inner surface portion of the corresponding lateral outer tube 56. A corresponding inert gas is supplied to the gap portion set between the outer end portion of the second wall portion 64b of the valve 64 and the corresponding inner surface portion of the lateral outer tube 56. Therefore, the polycrystalline silicon generated in the reactor 10 and related substances related thereto are prevented from entering the gap portion unnecessarily, and the solidified related substance adheres to the valve 64 and the valve 64 is It is prevented from sticking.

  When the peeling process for moving the rod member 24b up and down in this way is completed, the valve 64 of the upper valve device 40 is opened, and the polycrystalline silicon deposited on the valve 64 is loaded by its own weight into the valve of the lower valve device 104. After depositing on 104a, the valve 104a is opened, and the polycrystalline silicon deposited on the valve 104a is dropped into the silicon recovery tank 106 by its own weight.

  Thereafter, the valves 64 and 104a are closed again in order to shut off the inside of the reactor 10 from the outside, while the polycrystalline silicon in the silicon recovery tank 106 is taken out and recovered. The process is completed, and a series of steps of the next silicon manufacturing method is entered continuously as necessary. Here, since the silicon recovery tank 106 is detachable with respect to the silicon manufacturing apparatus 1, after the silicon has dropped, the silicon recovery tank 106 is removed from the silicon manufacturing apparatus 1 after closing the valve 104a. It is also possible to move to a predetermined storage location and take out the polycrystalline silicon inside the silicon recovery tank 106.

  Here, when a series of steps are repeated several times in such a silicon production method, the inner wall surface of the inner tube 26 deteriorates. Therefore, the inner tube 26 whose number of repetitions exceeds the reference number is determined from the reactor 10. It is removed and replaced with a new inner pipe 26.

  Various modifications can be considered for the upper valve device 40 in the silicon manufacturing apparatus 1 having the above configuration. Therefore, as one of such modifications, the upper valve device 140 will be described as an example and will be described in detail below with reference to FIG.

  3, FIG. 3A is a schematic longitudinal sectional view of the upper valve device of the present modification, and FIG. 3B is a sectional view taken along the line AA of FIG. 3A.

  The upper valve device 140 in the present modification is mainly different from the above-described upper valve device 40 in the configuration of the outer tube 150, the inner tube 160, and the like. The same reference numerals are assigned to the same components, and the description will be simplified or omitted as appropriate.

  As shown in FIGS. 3A and 3B, in the upper valve device 140 in this modification, the outer pipes 150 are typically coaxial with the central axis C and extend in the vertical direction in order. Has a cylindrical upper longitudinal outer tube 152 and a lower longitudinal outer tube 154 and a typically cylindrical lateral outer tube 156 extending in the direction of the central axis CL perpendicular to the central axis C, as described above. The horizontal outer tube 156 has a diameter-enlarged portion 156e in which the horizontal outer tube 156 has a larger diameter around the upper vertical outer tube 152 and the lower vertical outer tube 154. In the expanded diameter portion 156e, a pair of insertion holes 156c and 156d are formed so as to penetrate the wall portion of the lateral outer tube 156 and face each other.

Corresponding to the configuration in which the horizontal outer tube 156 has the enlarged diameter portion 156e, the upper vertical outer tube 152 and the lower vertical outer tube 154 are both shortened in length, and the upper vertical outer tube The lower end 152b of 152 is inserted and welded into the upper insertion hole 156c in the enlarged diameter portion 156e of the lateral outer tube 156. On the other hand, the upper end 154b of the lower vertical outer tube 154 is inserted and welded into the lower insertion hole 156d in the enlarged diameter portion 156e of the horizontal outer tube 156. Here, since the upper vertical outer tube 152 and the lower vertical outer tube 154 have a relatively small diameter because the lower heater 100 is downsized, each of the upper vertical outer tube 152 and the lower vertical outer tube has a small diameter. Similarly, welding 154 to the small-diameter horizontal tube 156 is complicated, such as requiring accuracy in the welding process. However, the lateral outer tube 156 is provided with the enlarged-diameter portion 156e, and the expansion is performed. If the upper vertical outer tube 152 and the lower vertical outer tube 154 are welded to the diameter portion 156e, the welding process is simplified and the strength of the entire welded structure is also improved.

  Corresponding to the configuration in which the lateral outer tube 156 has the enlarged diameter portion 156e as described above, the inner tube main body portion 162 also has the enlarged diameter portion 162e, the flange 156a is enlarged, and the valve 164 The first wall portion 164a and the second wall portion 164b are also enlarged in diameter. A side plate 176 having a correspondingly large diameter is fixed to the flange 156a of the lateral outer tube 156.

  Further, in this modification, the inert gas supply mechanism is configured to uniformly distribute the inert gas from the inert gas supply source (not shown) via the inert gas supply pipes 74 and 78 of the inner pipe main body 162. A gap portion set between the outer surface portion and the outer end portion of the first wall portion 164a of the valve 164 and the corresponding inner surface portion of the lateral outer tube 156, or the outer end portion of the second wall portion 164b of the valve 164 , And a corresponding gap portion set between the inner surface portion of the corresponding lateral outer tube 156.

  Specifically, the inert gas supply pipe 74 is typically inserted through and fixed to an insertion hole 180a formed in an annular flow channel member 180 made of quartz. The outer tube 156 is fixed by being inserted into an insertion hole 156c that penetrates the wall of the outer tube 156 over the entire circumference. With this configuration, the lateral outer tube 156 corresponding to the outer surface portion of the inner tube main body portion 162 and the outer end portion of the first wall portion 164a of the valve 164 is sequentially passed through the inert gas supply tube 74 and the annular flow path member 180. Inert gas can be uniformly supplied to the gap portion set between the inner surface portion and the polycrystalline silicon generated in the reactor 10 and falling downwardly, and related substances related thereto. , It is possible to more reliably prevent unnecessary entry into the gap.

  Further, the inert gas supply pipe 78 is typically inserted into and fixed to an insertion hole 190 a formed in the quartz chamber pipe 190, and the chamber pipe 190 is connected to the flange 156 a of the lateral outer pipe 156. It is fixed to the fixed side plate 176. With this configuration, the lateral outer tube 156 corresponding to the outer end portion of the second wall portion 164b of the valve 164 is sequentially passed through the inert gas supply tube 78, the chamber tube 190, and the insertion hole 176a formed in the side plate 176. Inert gas can be supplied more homogeneously to the gap set between the inner surface and the polycrystalline silicon produced in the reactor 10 and falling downward and related substances related thereto However, it is possible to more surely prevent unnecessary entry into the gap.

  The configurations related to the annular flow path member 180 and the chamber tube 190 can be appropriately combined with or selectively applied to the upper valve device 40 described above.

(Second Embodiment)
Next, the high temperature valve device according to the second embodiment of the present invention will be described in detail with reference to FIG.

  FIG. 4 is a schematic longitudinal sectional view of the silicon manufacturing apparatus used in the present embodiment.

  In the present embodiment, the detailed configuration of the silicon manufacturing apparatus 2 to which the upper valve device 40 described in the first embodiment and the upper valve device 140 described in the modification thereof can be applied has been described in the first embodiment. Since the main difference is that it differs from that of the silicon manufacturing apparatus 1, the following description will be made with a focus on such difference. Or omitted.

As shown in FIG. 4, the silicon manufacturing apparatus 2 in the present embodiment has a configuration in which the peeling mechanism 24 of the silicon manufacturing apparatus 1 described in the first embodiment is replaced with a shock blow gas supply pipe 124.

  Specifically, each of a plurality of 12c formed on the upper lid 12 of the reactor 10 is replaced with a high-pressure inert gas (not shown) instead of the introduction pipe 24a of the peeling mechanism 24 in the first embodiment. A shock blow gas supply pipe 124, typically made of quartz, is inserted and fixed in communication with the supply source. The shock blow gas supply pipe 124 penetrates into the reactor 10 and has a shock blow gas supply port 124a that extends coaxially with the central axis C and extends vertically downward, and opens at the tip in the vertical direction.

  Here, the shock blow gas supply port 124a of the shock blow gas supply pipe 124 opens at a position of a length L5 from the mating surface to the upper lid 12 of the reactor 10. The opening position of the shock blow gas supply port 124a needs to discharge a high-pressure inert gas from the shock blow gas supply port 124a to the precipitation region S defined on the inner wall surface of the inner tube 26 of the reactor 10. For this reason, it is preferable to be close to the deposition region S and above the deposition region S, so that it is typically below the opening position of the silicon tetrachloride gas supply port 16a and above the deposition region S. (L1 <L4 <L3 <L2 <L5).

    The shock blow conditions include the pressure of the inert gas discharged from the shock blow gas supply port 124a and the blow time. If the pressure is too low, silicon deposited in the precipitation region S cannot be sufficiently peeled off. On the other hand, if the pressure is too high, the vertical wall of the inner pipe 26 and the shock blow gas supply pipe 124 tend to be damaged. The range of 0.1 MPa to 1.0 MPa is preferable, and the range of 0.3 MPa to 0.6 MPa is more preferable for practical use. If the blowing time is too short, the silicon deposited in the precipitation region S cannot be sufficiently peeled. On the other hand, if the blowing time is too long, the introduction amount of the inert gas for shock blowing increases and the temperature of the reactor 10 decreases. Or the exfoliated silicon tends to be exhausted together with the exhaust gas and cannot be recovered. Therefore, the range of 0.1 second to 3.0 seconds is preferable. It may be repeated periodically.

  In the silicon manufacturing method for manufacturing polycrystalline silicon using the silicon manufacturing apparatus 2 having the above configuration, the inner wall surface of the inner tube 26 is defined in the reduction reaction step, as in the first embodiment. After depositing polycrystalline silicon in the precipitation region S, the polycrystalline silicon in the precipitation region S is peeled off by a shock blowing step using the shock blow gas supply pipe 124 instead of the peeling step using the peeling mechanism 24. Then, the polycrystalline silicon deposited on the valve 64 of the upper valve device 40 and the valve 104a of the lower valve device 104 is sequentially dropped and recovered by dropping into the silicon collection tank 106 by its own weight.

  Here, the upper valve device applicable to the silicon manufacturing apparatus 2 having the above configuration is not limited to the upper valve device 40 according to the first embodiment, and the upper valve device 140 according to the modification of the first embodiment. There may be.

  The upper valve device 40 in the first embodiment and the upper valve device 140 in the modification of the first embodiment are the silicon manufacturing device 1 in the first embodiment and the silicon manufacturing device 2 in the second embodiment. In addition to being able to be applied to the above, a silicon production apparatus having a configuration in which silicon is generated in the reactor, and such silicon, together with its by-products and raw materials, can be sent downward toward the silicon extraction portion. On the other hand, for example, the present invention can be suitably applied even when the reactor is in a horizontal arrangement or the silicon production process is different.

In the above embodiment, the inner tube 26 is disposed in the reactor 10 in consideration of the convenience of replacement. However, if the reactor 10 itself can be replaced as appropriate, It is also possible to omit the inner tube 26 and set the silicon deposition region S directly on the inner wall surface of the reactor 10.

  In each of the above embodiments, the configuration in which the zinc gas supply port 18a is disposed above the silicon tetrachloride gas supply port 16a has been described. However, the configuration is not limited to this, and the configuration is complicated. However, when the gas diffusibility and the like can be adjusted by controlling the gas discharge direction and flow velocity, the zinc gas supply port 18a is disposed at the same height or lower than the silicon tetrachloride gas supply port 16a. It is also possible to adopt such a configuration.

  Further, in each of the above embodiments, the upper heater 22 and the lower heater 100 tend to increase the size of the entire heater, but they can be integrated in terms of the function of the heater. is there.

  In each of the above embodiments, the reactor, the top cover, the bottom plate, the inert gas supply pipe, the silicon tetrachloride gas supply pipe, the zinc gas supply pipe, the exhaust pipe, the inner pipe, the rod member, the annular flow path member, and the chamber pipe As a material of each tubular member and valve of the upper valve device including the shock blow gas supply pipe, a material that can withstand the raw material silicon tetrachloride gas, zinc gas, by-product zinc chloride gas, etc. at a high temperature of 950 ° C. or higher Quartz, silicon carbide, silicon nitride and the like can be mentioned because of this, but from the viewpoint of avoiding mixing of carbon and nitrogen into the deposited silicon, quartz, specifically, quartz glass is most preferable. In addition, the material of the expansion tube is not particularly limited and may be made of metal or resin, but is preferably made of metal from the viewpoint of heat resistance.

  In the above embodiment, examples of the inert gas include rare gases such as He gas, Ne gas, Ar gas, Kr gas, Xe gas, and Rn gas, nitrogen gas, and the like. From the standpoint of avoiding nitrogen contamination, a rare gas is preferable, and Ar gas, which is inexpensive, is most preferable.

  Now, each experimental example and comparative example corresponding to each of the above embodiments will be described in detail.

(Experimental example 1)
In this experimental example, polycrystalline silicon was manufactured using the silicon manufacturing apparatus 1 to which the upper valve device 40 in the first embodiment was applied.

  Specifically, in the silicon production apparatus 1, the quartz reactor 10 has an outer diameter D set to 226 mm (thickness is 3 mm, inner diameter is 220 mm) and length L is set to 2330 mm, and the quartz inner tube 26, the outer diameter is set to 206 mm (the wall thickness is 3 mm, the inner diameter is 200 mm), and the length L4 of the upper end 26a from the mating surface to the upper lid 12 of the reactor 10 is set to 50 mm. No. 18 has an outer diameter set to 42 mm (wall thickness is 3 mm, inner diameter is 36 mm), and closes the lower end of the zinc gas supply pipe 18 so that only the vertical wall has an equal interval of 120 ° with respect to the central axis C. The opening position (the center position of the opening) of three zinc gas supply ports 18a provided at 16 mm is set so that the length L3 from the mating surface to the upper lid 12 of the reactor 10 is 300 mm, and the reactor Exhaust gas connected to the bottom of 10 Exhaust pipe 20 made of quartz having an inlet 20a, the outer diameter 56 mm (wall thickness is 2 mm, internal diameter 52 mm) was set on.

  Further, three quartz inert gas supply pipes 14 and quartz silicon tetrachloride gas supply pipes 16 disposed therein are arranged at a distance of 85 mm from the central axis C at equal intervals of 120 degrees. Then, three rod members 24b of each peeling mechanism 24 were disposed at equal intervals of 120 ° at a distance of 85 mm from the central axis C with the three inert gas supply pipes 14 correspondingly interposed therebetween.

  Here, each inert gas supply pipe 14 has an outer diameter set to 16 mm (thickness is 1 mm, inner diameter is 14 mm), and the opening position of the inert gas supply port 14a (reactor of the inert gas supply pipe 14). 10 is set so that the length L1 from the mating surface to the top lid 12 of the reactor 10 is 10 mm, and each silicon tetrachloride gas supply pipe 16 has an outer diameter of 9 mm (wall thickness). Is set to 1 mm and the inner diameter is 7 mm), and the silicon tetrachloride gas supply is provided by closing the lower end of the silicon tetrachloride gas supply pipe 16 so that only the vertical wall has a diameter of 4 mm and faces the inner wall of the inner pipe 26. The opening position of the mouth 16a (the center position of the opening) was set so that the length L2 from the mating surface to the upper lid 12 of the reactor 10 was 500 mm.

  Further, for each peeling mechanism 24, the rod member 24b is made of quartz and is a columnar rod member extending in the vertical direction, and its outer diameter is set to 9 mm and length 1900 mm. As a metal, its natural length was set to 100 mm and its spring constant was set to 0.15 kg / mm, and the weight 24d was made of iron and its weight was set to 3 kg. As an initial state of the peeling mechanism 24, the load of the weight 24d was previously applied to the telescopic tube 24c, and the bar member 24b was positioned at the lowest position.

  In the above specific configuration, in order to shut off the inside of the reactor 10 from the outside, first, the valve 64a of the upper valve device 40 and the valve 104a of the lower valve device 104 are closed. Ar gas having a flow rate of 0.83 SLM from the inert gas supply port 14 a, Ar gas having a flow rate of 1.00 SLM from the silicon tetrachloride gas supply port 16 a of the silicon tetrachloride gas supply tube 16, and zinc gas in the zinc gas supply tube 18 Ar gas having a flow rate of 0.84 SLM (Ar gas having a total flow rate of 2.67 SLM) was discharged into the reactor 10 from the supply port 18a.

  Next, with the Ar gas supplied to the inside of the reactor 10 as described above, the upper heater 22 is energized, and the first heating unit 22a causes the corresponding vertical wall of the reactor 10 and the inner pipe 26 to The vertical wall and its inner region are heated and maintained at 1200 ° C., and the corresponding vertical wall of the reactor 10, the inner wall of the inner pipe 26 and its inner region are 1100 ° C. by the second heating unit 22 b. The temperature was raised and maintained so that the vertical wall of the corresponding reactor 10, the vertical wall of the inner tube 26, and the region inside thereof were 1000 ° C. by the third heating unit 22c. .

  At the same time, the lower heater 100 is energized to raise the temperature so that the region including the upper vertical outer pipe 52 and the valve 64 from the bottom plate 30 attached to the reactor 10 to the valve 64 of the upper valve device 40 is 950 ° C. And maintained.

  Next, the upper heater 22 is energized as described above, and the first heating unit 22a, the second heating unit 22b, and the third heating unit 22c are respectively connected to the vertical wall of the reactor 10 and the vertical wall of the inner tube 26, respectively. In addition, the lower heater 100 is energized to heat the area including the upper vertical outer pipe 52 and the valve 64 extending from the bottom plate 30 attached to the reactor 10 to the valve 64. In this state, a mixed gas obtained by mixing zinc gas with a flow rate of 10.000 SLM in addition to Ar gas is discharged into the reactor 10 from the zinc gas supply port 18a of the zinc gas supply pipe 18 at a flow rate of 10.84 SLM. did. At the same time, while discharging Ar gas at a flow rate of 0.83 SLM from the inert gas supply port 14a of the inert gas supply pipe 14 into the reactor 10, the gas in the silicon tetrachloride gas supply pipe 16 is tetrachlorided from the Ar gas. Switching to silicon gas, silicon tetrachloride gas having a flow rate of 5.00 SLM was discharged into the reactor 10 from the silicon tetrachloride gas supply port 16a and allowed to react for 120 minutes.

  At this time, the inert gas supply pipes 74 and 78 are set between the outer surface portion of the inner tube main body portion 62 and the outer end portion of the first wall portion 64a of the valve 64 and the inner surface portion of the corresponding lateral outer tube 56. 3 corresponding to each of the gap portion set between the outer end portion of the second wall portion 64b of the valve 64 and the corresponding inner surface portion of the lateral outer tube 56, respectively. Supplied at a flow rate of 5 SLM.

  Next, after reacting for 120 minutes in this way, the supply of silicon tetrachloride gas and zinc gas, which are raw materials for the reaction, was stopped while the energization of the upper heater 22 and the lower heater 100 was maintained. Thereafter, again, Ar gas at a flow rate of 200 SLM from the inert gas supply port 14 a of the inert gas supply pipe 14, Ar gas at a flow rate of 200 SLM from the silicon tetrachloride gas supply port 16 a of the silicon tetrachloride gas supply pipe 16, and zinc gas Ar gas at a flow rate of 200 SLM was discharged from the zinc gas supply port 18a of the supply pipe 18 into the reactor 10, and the inside of the reactor 10 was replaced with Ar gas for 5 minutes. At this time, Ar gas is continuously supplied from the inert gas supply pipes 74 and 78.

  Next, after replacing with Ar gas in this way, the actuator 24e unlocked the weight 24d and pulled it up, so that the telescopic tube 24c extended about 20 mm, thereby moving the bar member 24b vertically upward by about 20 mm. Thereafter, the weight 24d is again pushed down by the actuator 24e and the load is applied to the telescopic tube 24c, the telescopic tube 24c is contracted by about 20 mm, and the bar member 24b is returned to a position vertically lowered by about 20 mm.

  Then, after repeating the above series of steps of 120 minutes of reaction, 5 minutes of replacement with Ar gas, and up and down movement of the rod twice in total, the upper valve device 40 connected below the reactor 10. After the polycrystalline silicon deposited on the valve 64 is dropped and deposited on the valve 104a of the lower valve device 104 by its own weight, the valve 104a of the lower valve device 104 is opened to recover the silicon. The deposit on the valve 104a was dropped into the tank 106, and the recovered substance in the silicon recovery tank 106 was confirmed. As a result, acicular polycrystalline silicon was present.

  Such needle-like polycrystalline silicon is separated by the vertical movement operation of the rod member 24b after silicon is deposited on the inner wall surface of the inner tube 26 in the reactor 10, and the valve 64 of the upper valve device 40 and the lower valve device 104 are separated. It is considered that what was sequentially deposited on the valve 104a was recovered.

  Further, the weight of the acicular polycrystalline silicon was measured and found to be 789 g, and the reaction rate of silicon tetrachloride gas subjected to the reaction was 53%. Furthermore, although the recovered material in the silicon recovery tank 106 contained zinc and zinc chloride, the total weight was 7 g, which was only 1% of the weight of the polycrystalline silicon. This is because the heating area including the upper vertical outer pipe 52 and the valve 64 from the bottom plate 30 attached to the reactor 10 to the valve 64 is heated and maintained to a temperature of 950 ° C. by the lower heater 100. It is considered that the deposition on the valve 64 in a state where zinc and zinc chloride are solidified is reduced.

  Further, when the acicular polycrystalline silicon was observed with an optical microscope, a colorless and transparent quartz piece as a material of the inner tube 26 was not recognized. This is because the rod member 24b of the peeling mechanism 24 is moved up and down to peel silicon deposited on the inner wall surface of the inner tube 26 of the reactor 10, thereby preventing the quartz pieces from being mixed into the recovered polycrystalline silicon. It is thought that it was made.

(Experimental example 2)
In this experimental example, the silicon manufacturing apparatus 2 according to the second embodiment having a configuration in which the peeling mechanism 24 is replaced with a shock blow gas supply pipe 124 in the silicon manufacturing apparatus 1 to which the upper valve device 40 according to the first embodiment is applied. Polycrystalline silicon was produced in the same manner as in Experimental Example 1 except that it was used.

Specifically, three shock blow gas supply pipes were disposed at an equal interval of 120 ° at a distance of 85 mm from the central axis C with the three inert gas supply pipes 14 correspondingly sandwiched therebetween. Each of the shock blow gas supply pipes 124 has an outer diameter set to 9 mm (thickness is 1 mm, inner diameter is 7 mm), and the opening position of the shock blow gas supply port 124a (in the reactor 10 of the shock blow gas supply pipe 124) The end position was set so that the length from the mating surface to the upper lid 12 of the reactor 10 was 600 mm.

  In the above specific configuration, the same steps as in the experimental example were performed, and after reacting with zinc and silicon tetrachloride for 120 minutes, Ar gas was substituted for 5 minutes. Thereafter, Ar gas was discharged at a high pressure from the shock blow gas supply port 124a of the shock blow gas supply pipe 124 to perform shock blow. The shock blow conditions at this time are as follows: the pressure of Ar gas is 0.4 MPa, the time of one shock blow is set to 0.5 seconds, and the interval until the next shock blow is 3.0 seconds, for a total of 15 Shock blows were performed.

  Then, after repeating the above-mentioned series of steps of 120 minutes of reaction, 5 minutes of replacement with Ar gas, and 15 shock blows with Ar gas twice in total, the upper valve device 40 connected below the reactor 10. After the polycrystalline silicon deposited on the valve 64 is dropped and deposited on the valve 104a of the lower valve device 104 by its own weight, the valve 104a of the lower valve device 104 is opened to recover the silicon. The deposit on the valve 104a was dropped into the tank 106, and the recovered substance in the silicon recovery tank 106 was confirmed. As a result, acicular polycrystalline silicon was present.

  Such needle-like polycrystalline silicon is separated by the vertical movement operation of the rod member 24b after silicon is deposited on the inner wall surface of the inner tube 26 in the reactor 10, and the valve 64 of the upper valve device 40 and the lower valve device 104 are separated. It is considered that what was sequentially deposited on the valve 104a was recovered.

  Moreover, when the weight of this acicular polycrystalline silicon was measured, it was 755 g, and the reaction rate of the silicon tetrachloride gas used for reaction was 50%. Furthermore, although the recovered material in the silicon recovery tank 106 contained zinc and zinc chloride, the total weight was 8 g, which was only 1% of the weight of the polycrystalline silicon. This is because the heating area including the upper vertical outer pipe 52 and the valve 64 from the bottom plate 30 attached to the reactor 10 to the valve 64 is heated and maintained to a temperature of 950 ° C. by the lower heater 100. It is considered that the deposition on the valve 64 in a state where zinc and zinc chloride are solidified is reduced.

  Here, when the acicular polycrystalline silicon was observed with an optical microscope, a colorless and transparent quartz piece was mixed although it was a trace amount. Further, as a result of visually observing the inner wall surface of the portion corresponding to the silicon precipitation region S of the inner tube 26, innumerable cracks were observed. This is because Ar gas having a low temperature is blown to the interface between the inner wall surface of the quartz inner tube 26 and silicon at the time of shock blow, and due to the difference in thermal expansion coefficient between these two types of materials, It is considered that stress was generated on the inner wall surface, and a part of the inner wall surface of the inner tube 26 was peeled off and dropped into the silicon recovered by dropping downward together with the silicon.

(Comparative Example 1)
In this comparative example, polycrystalline silicon was manufactured in the same manner as in Experimental Example 1 except that a silicon manufacturing apparatus having a configuration in which the upper valve device 40 was omitted from the configuration in Experimental Example 1 was used.

As a result, when the recovered substance in the silicon recovery tank 106 was confirmed, a large amount of zinc and zinc chloride existed in addition to the acicular polycrystalline silicon. The weight of the acicular polycrystalline silicon was measured and found to be 766 g. The reaction rate of silicon tetrachloride gas used for the reaction was 51%. Moreover, it was 489g when the weight of zinc and zinc chloride was measured. Further, when the acicular polycrystalline silicon was observed with an optical microscope, a colorless and transparent quartz piece as a material of the inner tube 26 was not recognized.

(Comparative Example 2)
In this comparative example, polycrystalline silicon was manufactured in the same manner as in Experimental Example 2 except that a silicon manufacturing apparatus having a configuration in which the upper valve device 40 was omitted from the configuration in Experimental Example 2 was used.

  As a result, when the recovered substance in the silicon recovery tank 106 was confirmed, a large amount of zinc and zinc chloride existed in addition to the acicular polycrystalline silicon. The weight of the acicular polycrystalline silicon was measured and found to be 781 g. The reaction rate of the silicon tetrachloride gas used for the reaction was 52%. Moreover, it was 499 g when the weight of zinc and zinc chloride was measured. Further, when the acicular polycrystalline silicon was observed with an optical microscope, a colorless and transparent quartz piece was mixed although it was a trace amount.

  From each of the above experimental examples and each comparative example, in each experimental example, zinc and zinc chloride can be significantly reduced in the recovered polycrystalline silicon as seen in each comparative example. It can be said that the significance of providing a high-temperature valve device below the reactor was confirmed.

  In the present invention, the type, arrangement, number, and the like of the members are not limited to the above-described embodiments, and the components depart from the gist of the invention, such as appropriately replacing the constituent elements with those having the same operational effects. Of course, it can be appropriately changed within the range not to be.

  As described above, in the present invention, high corrosion resistance can be exhibited, and reaction by-products and reaction raw materials for producing silicon are maintained in a gas state that is completely different from the phase state of solid silicon. It is possible to provide a high-temperature valve device having a simple configuration that can be mechanically separated while being widely applicable to manufacturing apparatuses for silicon for solar cells, etc., because of its universality. It is expected.

DESCRIPTION OF SYMBOLS 1 ......... Silicon production apparatus 10 ... Reactor 10a ... Insertion hole 12 ... Upper lid 12a, 12b, 12c ... Insertion hole 14 ... Inert gas supply pipe 14a ... Inert gas supply port 16 ... Silicon tetrachloride gas Supply pipe 16a ... Silicon tetrachloride gas supply port 18 ... Zinc gas supply pipe 18a ... Zinc gas supply port 20 ... Exhaust pipe 20a ... Exhaust inlet 22 ... Upper heater 22a ... First heating part 22b ... Second heating Part 22c ... Third heating part 22d ... Through hole 24 ... Peeling mechanism 24a ... Introduction pipe 24b ... Rod member 24c ... Expandable pipe 24d ... Weight 24e ... Actuator 26 ... Inner pipe 26a ... Upper end 26b ... Insertion hole 30 ... Bottom plate 30a ... through hole 32 ... guide member 40,140 ... upper valve device 50,150 ... outer pipe 52,152 ... upper vertical outer pipe 52a ... upper end flange 52b, 152b ... lower end 54 ...... Downward vertical outer pipe 54a ... Lower end flange 54b, 154b ... Upper end 56,156 ... Horizontal outer pipe 56a, 156a ... Flange 56b ... Diametered portion 56c, 56d, 156c, 156d ... Insertion hole 60,160 ... Inner pipe 62 162 ... Inner pipe main body 62a ... Other end 62b ... Communication hole 64, 164 ... Valve 64a, 164a ... First wall 64b, 164b ... Second wall 64c ... Valve main body 70 ... Gland seal 72 ...... Pressing member 74 ...... Inert gas supply pipe 76 ...... Side plate 76 a .. Insertion hole 78 ...... Inert gas supply pipe 100 .. Lower heater 102 .. Communication pipe 104 .. Lower valve device 104 a. 124 ... Shock blow gas supply pipe 124a ... Shock blow gas supply port 176 ... Side plate 176a ... Insertion hole 180 ... Annular flow path Material 180a, 190a ... Insertion hole 190 ... Chamber tube

Claims (11)

A high-temperature valve device that can be placed below a reactor for generating silicon,
A first tubular member that communicates with the internal space of the reactor and is capable of introducing silicon produced in the reactor;
A valve disposed within the first tubular member;
A heater capable of heating a part of the first tubular member extending from the reactor to the valve and a heating region including the valve above a boiling point of a related substance related to generation of silicon in the reactor;
High temperature valve device with   The first tubular member includes a longitudinal outer tube extending in a first direction parallel to a vertical direction, and a lateral outer tube extending in a second direction orthogonal to the first direction. The high-temperature valve device according to claim 1, wherein the valve is provided in a second tubular member that extends rotatably in the lateral outer tube.   The high-temperature valve device according to claim 2, further comprising an inert gas supply mechanism that supplies an inert gas to a gap portion defined between the lateral outer tube and the second tubular member.   The high temperature valve device according to claim 2 or 3, wherein the second tubular member is rotatably disposed in the lateral outer tube via a ground seal.   The high temperature valve device according to claim 4, wherein the ground seal is disposed outside the heating region of the heater.   The second tubular member has an inner tube closed at one end which is a wall portion connected to the valve and the other end facing the one end, and the other end is an internal space of the inner tube. The high-temperature valve device according to claim 2, further comprising a communication hole that communicates with the outside.   The lateral outer pipe has an enlarged diameter part obtained by enlarging the lateral outer pipe, and the longitudinal outer pipe and the lateral outer pipe are connected to each other via the enlarged diameter part. The high temperature valve device according to any one of the above.   The inert gas supply mechanism has an annular flow path member provided in the lateral outer pipe, and the inert gas supplied from the inert gas supply mechanism passes through the internal space of the annular flow path member, The high temperature valve device according to any one of claims 3 to 7, which is supplied to the gap portion.   The inert gas supply mechanism has a chamber tube fixed to a side plate that closes one end portion of the lateral outer tube, and the inert gas supplied from the inert gas supply mechanism further passes through the chamber tube. The high-temperature valve device according to any one of claims 3 to 8, wherein the high-temperature valve device is supplied to an internal space of the lateral outer pipe.   The high-temperature valve device according to any one of claims 1 to 9, wherein the related substance is introduced into the first tubular member through a funnel-shaped guide member provided in the reactor.   The high temperature valve device according to any one of claims 1 to 10, wherein the related substance includes zinc and zinc chloride.

Images