JP2009234831A - Silicon production apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silicon production apparatus in which silicon deposition on a wall surface of a reactor, etc., is avoided and the amount of silicon which is discharged with gas discharged from the reactor and is not recovered and the loss of unreacted raw material gas are minimized, and which can continuously mass-produce solid silicon of constant quality and constant form. <P>SOLUTION: The silicon production apparatus includes a first reactor 1 and a second reactor 2 connected to the first reactor on a downstream side of the first reactor. In the first reactor, a silicon compound is reduced with zinc to form solid silicon. In the second reactor, while using solid silicon of relatively small crystal size in the solid silicon formed in the first reactor as seed crystals, a silicon compound is reduced with zinc to form solid silicon. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a silicon production apparatus, and more particularly to a silicon production apparatus in which a second reactor is provided downstream of a first reactor.

In recent years, the production method of obtaining high purity silicon by reducing silicon tetrachloride with zinc by the so-called zinc reduction method is that the equipment is compact and consumes little energy, and high purity silicon of 6-nine or more can be obtained. Therefore, it has been attracting attention as a method for producing silicon for solar cells, for which demand is expected to increase rapidly in the future. The reaction formula of the zinc reduction method is represented by SiCl ₄ + 2Zn → Si + 2ZnCl ₂ .

  The purity of silicon required as a raw material of a semiconductor is required to be higher than that of 8-nine in an integrated circuit application, and purified by a method called a Siemens method in which silicon trichloride gas is reduced with hydrogen gas. It is possible to divert and use the offcuts and off-spec products at this time for solar cell applications, but there are certain limits to securing silicon production and cost reduction. There is an urgent need to develop a zinc reduction method that can be secured.

  Under such circumstances, as a zinc reduction method, a structure in which silicon tetrachloride gas heated to 950 ° C. or more and 1200 ° C. or less is brought into contact with zinc gas and solid silicon is deposited at the jet port of the silicon tetrachloride gas supply pipe. It is disclosed (see Patent Documents 1 and 2).

In addition, as a zinc reduction method, silicon seed crystals are placed in a reactor, fluidized by the raw material gas to be introduced and by-product zinc chloride gas, and silicon is deposited on the surface of the seed crystals constituting the fluidized bed. The configuration is disclosed (see Patent Documents 3 to 5 and Non-Patent Document 1).
JP 2007-145663 A JP 2007-223822 A JP 2003-342016 A JP 2004-10472 A Japanese Patent Laid-Open No. 11-92130 No. 216, Vol. 78 PROCESSING OF ENERGY AND METALLIC MINEALS AIChE SYMPOSIUM SERIES

  However, according to the study of the present inventors, in the configurations disclosed in Patent Documents 1 and 2, it is difficult to keep the reaction of silicon precipitation in a steady state due to fluctuations in pressure loss at the silicon tetrachloride jet, Moreover, since it is essential to stop the apparatus when collecting silicon, there is room for improvement in mass production of silicon of a certain quality.

  Further, in the configurations disclosed in Patent Documents 3 to 5 and Non-Patent Document 1, there is an increase in cost due to silicon seed crystals, and the contact between the source gas and the seed crystals is made uniform to form and maintain a stable fluidized bed. Since it is difficult to select a high-temperature and gas-corrosion-resistant material for manufacturing a complicated device, there is room for improvement in feasibility.

  Further investigations by the present inventors have revealed that non-adhesive needle-like or fibrous silicon can be recovered by avoiding silicon deposition on the reactor wall surface or the like under specific reaction conditions.

  Specifically, in a tubular reactor, silicon tetrachloride gas heated to 1100 ° C. or higher and zinc gas are brought into contact to obtain solid silicon and zinc chloride gas, and the precipitated solid silicon is separated by gravity. It is the structure which separates and collects both by dropping and extracting zinc chloride gas. At this time, out of the precipitated solid silicon, a large size crystal that does not accompany the gas flow mainly composed of zinc chloride falls and is recovered in the reactor, but the higher the raw material gas density in the reactor, It is known that large crystals can be obtained. This is presumably because fine primary crystals serve as nuclei, and silicon generated from the source gas in the vicinity accumulates on the surface and grows, and the probability increases if the source gas density is high. At this time, since the detection of the temperature in the reactor is complicated, the temperature of the outer surface of the reactor is detected, and the detected temperature is applied as the gas temperature in the reactor.

Here, in such a configuration, if the reaction conditions such as the molar ratio of the raw material gas components supplied to the reactor, the flow rate of the gas flow flowing in the reactor, the temperature, etc. are not properly controlled, Therefore, it is important for industrialization to optimally control such reaction conditions because an intermediate such as Si ₂ Cl ₆ is generated or a considerable amount of unreacted gas is generated. .

  In this case, the temperature condition is as high as 1100 ° C. or higher, and it is resistant to contamination, does not contaminate the recovered silicon, and the economically acceptable material for use of the reactor and its peripheral devices is quartz glass. There is a reality that is almost limited and that only a simple structure can be produced.

  The present invention has been made in view of such circumstances, avoiding silicon deposition on the reactor wall surface, etc., and reducing the amount of silicon that is discharged together with the gas discharged from the reactor and not recovered and the amount of unreacted raw material gas loss. To minimize the temperature distribution, raw material gas concentration distribution, and gas flow rate distribution in the reactor, solid silicon with a constant quality and shape can be continuously mass-produced and operated at a high temperature of 1100 ° C or higher. It aims at providing the silicon manufacturing apparatus by the zinc reduction method obtained.

  In view of such circumstances, the present invention constitutes a multistage reaction apparatus in which a plurality of reactors are arranged in series, and among solid silicon produced in each reactor, those that fall and can be recovered from the bottom of the reactor, and in the reactor It has been completed by finding that the yield can be improved by separating and processing fine substances accompanying the gas flow. That is, in the present invention, a configuration in which fine silicon is used as a seed crystal and silicon is further deposited on the surface of the subsequent reactor is completed.

At this time, the shape of the recovered silicon is preferably a needle shape having a diameter of about 1 mm for the purpose of post-processing as a raw material of the solar cell. In order to obtain such a silicon crystal, it is necessary to grow the crystal under the condition that the source gas is sufficiently present in the vicinity of the seed crystal serving as a nucleus. However, the operation under such conditions causes a loss of unreacted raw material gas because it is practically difficult to control the raw material gas supplied to the reactor at 100% without excessive or insufficient reaction. If the raw material gas discharged together with the by-product zinc chloride gas at this time is effectively used together with the newly supplied raw material gas in the subsequent reactor, this phenomenon can be overcome. In the subsequent reactor, since silicon is further deposited on the surface of the seed fine silicon as a nucleus, even if the raw material gas density is low, the same acicular silicon crystal as that obtained in the previous reactor is obtained. be able to. Even when an intermediate such as Si ₂ Cl ₆ is produced, it can be effectively used in the subsequent reactor.

  On the other hand, if the temperature in the reactor is not uniform, naturally the concentration of the gas in the reactor is generated and the shape of the deposited silicon also changes. However, such temperature distribution and gas density distribution can be advantageously used if a control target value can be determined and managed. That is, the configuration in which the contents of the reactor arranged in the vertical direction is cooled to a specific temperature only when passing through a specific portion in the height direction to increase the raw material gas density, and then heated to the vicinity of the original temperature again. As a result, it is possible to control the silicon precipitation reaction selectively in a portion convenient for product recovery, and to prevent blockage of the source gas supply pipe and the exhaust pipe.

  In other words, based on the above knowledge, the present inventors controlled the amount of cooling heat when the contained zinc chloride component is liquefied or solidified in the treatment process of the gas discharged from the reactor, and the gas passing through each reactor. In addition to controlling the flow rate and setting the temperature in each reactor to a steady state, the amount of raw material gas supplied to each reactor is controlled so that the pressure is within a predetermined range. It realizes a configuration that makes it possible to continuously mass-produce solid silicon with a constant quality and a constant shape by making precipitation constant.

  Furthermore, by utilizing the eddy current loss inside the conductor due to electromagnetic induction, the reactor itself is not heated to its use limit temperature, but only silicon is selectively heated to a semi-molten state temporarily when passing through a specific part in the reactor. In addition, a structure that promotes silicon deposition on the surface and fuses fine crystals with each other is also realized.

That is, in the first aspect, the present invention provides a first reactor, a first silicon compound gas supply system that communicates with the first reactor and supplies silicon compound gas into the first reactor, A first zinc gas supply system that communicates with the first reactor and supplies zinc gas into the first reactor; and a second reactor that communicates with the first communication section downstream of the first reactor. A second silicon compound gas supply system for supplying a silicon compound gas into the second reactor, and a second gas connected to the second reactor, and zinc gas for the second reaction. A second zinc gas supply system that supplies the silicon compound gas contained in the silicon compound gas supplied by the first silicon compound gas supply system to the first zinc gas. Solid silicon is produced by reduction with zinc contained in the zinc gas supplied by the supply system The second reactor is a relatively small portion of the solid silicon produced in the first reactor that has flowed into the second reactor through the first connecting portion. Zinc contained in the zinc gas supplied by the second zinc gas supply system, with a silicon compound contained in the silicon compound gas supplied by the second silicon compound gas supply system, while using solid silicon having a crystal size as a seed crystal This is a silicon production apparatus which is a reactor that produces solid silicon by reduction at a low temperature.
It is.

  In addition to the first aspect, the present invention provides that each of the first reactor and the second reactor has a melting point of the solid silicon inside each of the first reactor and the second reactor. The second aspect is to include an induction heating device that heats the vicinity.

  In addition to the first or second aspect, the present invention provides the first silicon compound gas supply system and the first zinc gas supply system, wherein the silicon compound gas and the zinc gas are supplied to the first reactor. Is maintained at a predetermined molar ratio and is supplied at a predetermined flow rate. The second silicon compound gas supply system and the second zinc gas supply system are connected to the second reactor with respect to the silicon compound gas. A third aspect is that the control system supplies the zinc gas at a predetermined flow rate while maintaining the predetermined molar ratio.

  According to the present invention, in addition to the third aspect, the first silicon compound gas supply system and the second silicon compound gas supply system include a gas supply source for supplying a silicon compound gas to a supply line, and the supply line. A flow rate detector for detecting a flow rate of the silicon compound gas flowing through the supply line, and a flow rate of the silicon compound gas flowing through the supply line based on a detection result of the flow rate detector, A fourth aspect includes a flow rate controller that controls the valve.

  In addition to the third or fourth aspect of the present invention, the first zinc gas supply system and the second zinc gas supply system include a liquid zinc supply source for supplying liquid zinc to a liquid zinc reservoir, and non-penetrating A rotating member having a hole formed therein and rotatably held is controlled by a feeder controller to control the flow rate of the liquid zinc fed from the liquid zinc reservoir by rotating the rotating member. A fifth aspect is to generate zinc gas from the liquid zinc fed from the quantitative feeder.

  In addition to any one of the first to fifth aspects, the present invention further includes a gas processing device communicated by a second communication unit downstream of the second reactor, and the gas processing device includes the first processing unit. 2. A processing apparatus for receiving the zinc compound gas by-produced in the first reactor and the zinc compound gas by-produced in the second reactor, which is liquefied or solidified, and flows in through the two communication sections, the zinc A sixth aspect includes a control system capable of controlling the flow rate of the gas passing through the first reactor and the second reactor while controlling the amount of decrease in the volume of the compound gas received.

  In addition to the sixth aspect of the present invention, the gas processing apparatus includes an air-cooling condenser that cools the inside thereof, and a cooling medium supply system that supplies a cooling medium to the air-cooling condenser. The cooling medium supply system includes: The seventh aspect is a control system that controls the cooling capacity of the air-cooled condenser.

  According to the present invention, in addition to the seventh aspect, the cooling medium supply system includes an air line that communicates with the air-cooling condenser, a cooler that maintains air flowing through the air line at a constant temperature, and the air line. An eighth aspect includes: a blower fan that blows the flowing air that is held at the constant temperature to the air-cooled condenser via the air line; and a transmission that controls a rotation operation of the blower fan. . An example of such a transmission is an inverter device.

  In addition to the eighth aspect of the present invention, the gas treatment apparatus further includes a zinc compound tank that receives the molten zinc compound liquefied by the air-cooled condenser, and the molten zinc compound that is stored in the zinc compound tank. A load cell that measures the weight of the blower fan, and the transmission controls the rotational operation of the blower fan so that the amount of change in the weight of the molten zinc compound measured by the load cell is constant. Let it be the ninth aspect.

  In addition to the sixth aspect of the present invention, the gas processing apparatus includes an ejector that generates a negative pressure therein, and an ejection medium supply system that supplies the ejection medium to the ejector, and the ejection medium supply system Is a control system for controlling the cooling capacity of the ejector as a tenth aspect.

  According to the present invention, in addition to the tenth aspect, the ejection medium supply system flows through the supply line, an ejection medium supply source that supplies the ejection medium to the supply line, a valve that can open and close the supply line, and the supply line. A flow rate detector for detecting the flow rate of the ejection medium; and a flow rate controller for controlling the flow rate of the ejection medium flowing through the supply line via the valve based on a detection result of the flow rate detector. Is the eleventh aspect.

  In addition to the eleventh aspect of the present invention, the gas treatment device further includes a zinc compound hopper that receives the solid zinc compound solidified by the ejector, and the solid zinc compound stored in the zinc compound hopper. A load cell for measuring weight, and the flow controller controls the opening of the valve so that the amount of change in the weight of the solid zinc compound measured by the load cell is constant. Let's say that.

Further, according to the present invention, in addition to any one of the fourth to twelfth aspects, the gas processing device includes an auxiliary reactor, and the auxiliary reactor passes through the second communication portion and passes through the auxiliary reactor. A reactor capable of generating solid silicon using unreacted gas that has flowed into the auxiliary reactor through the second communication portion while using solid silicon having a relatively small crystal size flowing into the seed as a seed crystal It is assumed that there is a thirteenth aspect.

  In addition to any one of the third to thirteenth aspects, the present invention further includes a heater for maintaining a constant temperature inside the first reactor and the second reactor, the first reactor, A controller for controlling the pressure inside the second reactor to a constant pressure, and the controller controls the inside of the first reactor and the second reactor to the constant pressure. The control system of the 1 silicon compound gas supply system and the first zinc gas supply system, the control system of the second silicon compound gas supply system and the second zinc gas supply system, or the control system of the gas processing apparatus. Control is a fourteenth aspect.

  According to the present invention, in addition to any one of the first to fourteenth aspects, the silicon compound gas supplied from the first silicon compound gas supply system to the first reactor is the first zinc. The silicon compound gas supplied from the second silicon compound gas supply system to the second reactor is supplied upstream from the zinc gas supplied from the gas supply system, and the second zinc gas is supplied to the second reactor. The fifteenth aspect is to be supplied upstream of the zinc gas supplied from the supply system.

  According to the present invention, various conditions for quantitatively carrying out the reduction reaction of silicon tetrachloride with zinc can be controlled under extremely limited apparatus design conditions for a high temperature corrosive gas process of 1100 ° C. or higher. Therefore, to avoid silicon deposition on the reactor wall, etc., and minimize the amount of silicon that is discharged together with the gas discharged from the reactor and not recovered and the amount of unreacted raw material gas loss, It is possible to provide a silicon production method by a zinc reduction method in which gas concentration distribution and gas flow velocity distribution are made steady, and solid silicon having a constant quality and shape is continuously mass-produced.

  Hereinafter, a silicon manufacturing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the figure, the z-axis indicates the vertical direction.

(First embodiment)
First, the silicon manufacturing apparatus according to the first embodiment of the present invention will be described in detail with reference to FIGS.

  FIG. 1 is a schematic configuration diagram of a silicon manufacturing apparatus according to the present embodiment. FIG. 2 is a schematic configuration diagram of a silicon tetrachloride gas supply system in the present embodiment. FIG. 3 is a schematic configuration diagram of a zinc gas supply system in the present embodiment. FIG. 4 is a schematic configuration diagram of a hot air supply system in the present embodiment.

  As shown in FIG. 1, the silicon production apparatus S <b> 1 includes a first reactor 1, a second reactor 2 connected downstream of the first reactor 1, and a gas connected downstream of the second reactor 2. And a processing device 3. Here, the first reactor 1, the second reactor 2, and the gas processing device 3 (specifically, an auxiliary reactor 60, which will be described in detail later) have a temperature detector (not shown) and have a control function. Surrounded by an external heater H, these interiors are heated under feedback control so as to have a constant temperature of 900 ° C. to 1300 ° C., more preferably 1100 ° C. to 1300 ° C. Although the heater H is not limited, a resistance heater or the like can be used, and the temperature of the first reactor 1 and the second reactor 2 is the outer surface temperature of each reactor for convenience of configuration. The detected temperature is typically used. The first reactor 1, the second reactor 2, and the gas treatment device 3 are all quartz glass tubular containers, and the first reactor 1 and the second reactor 2 are straight tubes and have a z-axis. Standing in parallel, the negative direction of the z-axis is the direction of gravity. Further, the downstream means the downstream of the gas flow flowing in the silicon manufacturing apparatus S.

  A silicon tetrachloride gas supply system 4 that supplies silicon tetrachloride gas that is a silicon compound gas to the first reactor 1 is connected to the supply port 4 a of the first reactor 1. Further, a zinc gas supply system 5 for supplying zinc gas to the first reactor 1 is communicated with the supply port 5 a of the first reactor 1. Here, in order to prevent silicon from depositing on the end of the supply port 4a to which the silicon tetrachloride gas is supplied on the first reaction vessel 1 side, the supply port 5a to which the zinc gas is supplied is provided with silicon tetrachloride. It is provided on the downstream side (the positive direction side of the z axis) from the supply port portion 4a to which the gas is supplied.

  More specifically, the silicon tetrachloride gas supply system 4 includes a supply line 11 and a supply that communicate between the silicon tetrachloride gas supply source 10 and the supply port 4a of the first reactor 1, as shown in FIG. The supply line 11 is provided with a flow rate detector 13 downstream of the valve 12 (rightward in FIG. 2). The flow rate detector 13 is connected to the supply line 11. 11 detects the flow rate of the silicon tetrachloride gas flowing through 11.

  The flow rate detection signal of the flow rate detector 13 is sent to the flow rate controller 14, and the flow rate controller 14 adjusts the opening degree of the valve 12 based on the input flow rate detection signal and flows through the supply line 11. The flow rate of silicon gas is controlled to a set flow rate. That is, the flow rate controller 14 controls the flow rate of the silicon tetrachloride gas flowing through the supply line 11 to a predetermined flow rate, and the silicon tetrachloride gas thus controlled to the predetermined flow rate is It will be supplied to the supply port 4a of the first reactor 1. Such control is feedback control.

  As shown in FIG. 3, the zinc gas supply system 5 gasifies and communicates liquid zinc between the liquid zinc supply source 20 and the supply port 5a of the first reactor 1, A liquid zinc reservoir 21 is communicated to the supply source 20, and a metering feeder 22 is communicated to the liquid zinc reservoir 21. The quantitative feeder 22 includes a rotating sphere 22a in which a closed hole (non-through hole) is formed and is rotatably held around a predetermined rotation axis R. The rotating sphere 22a is controlled by the feeder controller 22b. By rotating and feeding the liquid zinc accumulated in the closed hole (non-through hole), the liquid zinc fed from the liquid zinc reservoir 14 is further fed while being metered to a predetermined flow rate. Is. Such control is feedback control. The rotating sphere 22a of the quantitative feeder 22 is not limited to a spherical shape in shape, and may be a columnar member or the like as long as it can rotate around the rotation axis R.

  Further, a zinc heater 23 to which liquid zinc fed at a predetermined flow rate from the quantitative feeder 22 is supplied is communicated below the quantitative feeder 22 (in the negative direction of the z-axis). The zinc heater 23 has a heater 23a, and the heater 23a heats the liquid zinc supplied in this way to a boiling point or higher to gasify it. Further, the vapor separator 24 and the mist separator 25 are connected to the zinc heater 23, and the zinc gas generated by the zinc heater 23 is removed in the vapor separator 24 and the mist separator 25, and is not necessary. The liquid is supplied to the supply port 5a of the first reactor 1 without any accompanying liquid droplets.

  Here, between the silicon tetrachloride gas supplied to the supply port 4 a of the first reactor 1 and the zinc gas supplied to the supply port 5 a of the first reactor 1, there is zinc silicon tetrachloride. The quantitative relationship is maintained such that the molar ratio to 2 is 2.

  Thus, the silicon tetrachloride gas and the zinc gas supplied to the first reactor 1 are mixed and brought into contact with each other, and the silicon tetrachloride gas in contact with the zinc gas is reduced to produce solid silicon and by-product zinc. Zinc chloride gas, which is a compound gas, is generated. Here, the gas in the first reactor 1 contains unreacted silicon tetrachloride, zinc, an intermediate, and the like in addition to the by-product zinc chloride, upward (in the positive direction of the z axis). It becomes the flow to go. In addition, the generated solid silicon is relatively small in size so that it does not fall by being accompanied by a crystal that falls in the negative z-axis direction by gravity against such a gas flow. Small fine crystals. Further, in addition to the heater H, an induction heater Ha is locally provided in a part of the zinc gas supply port portion 5a in the first reactor 1 (positive direction of the z-axis), so that the first reactor By defining the induction heating zone 1a in FIG. 1, the solid silicon passing therethrough is selectively heated to the vicinity of the melting point, so that the solid silicon is more likely to be deposited around it. The increase in size is promoted. Note that the heater for locally heating is not limited to the induction heater Ha, and may be a locally provided resistance heater as long as it can be heated about 50 ° C. higher than the heating temperature by the heater H. Etc.

  Here, in the 1st reactor 1, the crystal | crystallization discharge | release apparatus 30 covered with the housing | casing 30a is provided in the edge part below the supply port part 4a (the negative direction of az axis) to which silicon tetrachloride gas is supplied. Is provided. The crystal discharging device 30 is provided with a rotating ball 30b in which a closed hole (non-through hole) is formed and held rotatably in the housing 30a in the same manner as the quantitative feeder 22, and an upper portion of the housing 30a. It has a supply port portion 31 a that communicates with the argon gas supply system 31, and also has a supply port portion 32 a that communicates with the argon gas supply system 32 at its lower part. Due to the argon gas supplied from the argon gas supply systems 31, 32, the upper space and the lower space of the box of the crystal discharge device 30 become an argon gas atmosphere. Further, the crystal discharge device 30 is connected to a solid silicon discharge system 33, and the solid silicon generated through the discharge device 33 is discharged and collected. The argon gas supply systems 31 and 32 may have a common argon gas source. In addition, the rotating sphere 30b of the crystal discharging device 30 is not limited to a spherical shape in shape like the rotating sphere 22a of the quantitative feeder 22, and may be a cylindrical member or the like.

  Further, a cooling device C for cooling the crystal discharge device 30, particularly the rotating ball 30 b and its related members, is provided between the supply port 4 a to which the silicon tetrachloride gas is supplied and the crystal discharge device 30. Yes. The cooling device C may be either a water cooling type or an air cooling type.

  Further, a pressure controller 35 that detects the pressure in the first reactor 1 and controls the pressure in the first reactor 1 between the supply port 4a to which the silicon tetrachloride gas is supplied and the cooling device C. Will contact you. The pressure controller 35 has a pressure detector that detects the pressure in the first reactor 1.

  In such a configuration, silicon crystals that fall in the negative z-axis direction due to gravity out of the generated solid silicon reach the crystal discharge device 30 from the lower end of the first reactor 1 and rotate in an argon gas atmosphere. Through the rotation of the sphere 30a, a set amount of silicon crystal is periodically discharged from the solid silicon discharge system 33 and collected. Here, since the upper space and the lower space of the box of the crystal discharge device 30 are in an argon gas atmosphere, unnecessary reaction gas and air are prevented from being mixed.

  On the other hand, a fine silicon crystal that does not fall in the negative direction of the z-axis is a gas containing unreacted silicon tetrachloride, zinc, intermediates, and by-product zinc chloride in the first reactor 1. Ascend with the flow of the. Here, since the upper end (the positive direction of the z-axis) of the first reactor 1 communicates with the second reactor 2 on the downstream side via the connecting portion 40, such a fine silicon crystal body Flows into the second reactor 2 together with a gas flow containing zinc chloride. Here, the basic configuration of the second reactor 2 is the same as that of the first reactor 1, and the same components as those of the first reactor 1 are denoted by the same reference numerals, and the description thereof will be appropriately described. Simplify or omit. Note that the silicon tetrachloride gas and the zinc gas supplied to the second reactor 2 may be more diluted than those of the first reactor 1. Further, the pressure controller 35 communicating with the first reactor 1 communicates with the second reactor 2 in the same manner, and detects the pressure in the second reactor 2. Further, the silicon tetrachloride gas supply system 4 and the zinc gas supply system 5 connected to the first reactor 1 and the second reactor 2 may be made common. Similarly, the induction heating zone 2a is defined in the second reactor 2 as well.

  Thus, the fine silicon crystal flowing into the second reactor 2 is converted into a gas containing unreacted silicon tetrachloride, zinc, intermediates, etc. and by-product zinc chloride in the first reactor 1. In addition, the silicon tetrachloride gas and the zinc gas supplied to the second reactor 2 are mixed in the same manner as in the first reactor 1, and contact with the silicon tetrachloride gas and the zinc gas in these, so that the fine silicon crystal New silicon will be deposited on the surface. That is, in this way, in the second reactor 2, the fine silicon crystal supplied from the first reactor 1 can be used as a seed crystal, and silicon can be newly deposited around it. As a result, a silicon crystal having a larger size can be generated.

  Also in the second reactor 2 having such a configuration, a silicon crystal that falls in the negative z-axis direction due to gravity among the generated solid silicon is a silicon crystal having a size larger than that in the first reactor. 2 From the lower end of the reactor 2 to the crystal discharge device 30, it is discharged from the solid silicon discharge system 33 and recovered with good yield.

  On the other hand, a fine silicon crystal that does not fall in the negative direction of the z-axis is a gas containing unreacted silicon tetrachloride, zinc, intermediates, and by-product zinc chloride in the second reactor 2. Ascend with the flow of the. Here, the upper end (the positive direction of the z-axis) of the second reactor 2 communicates with the gas processing device 3 on the downstream side via the communication unit 50, so that the fine silicon crystal body is Then, it flows into the gas processing apparatus 3 along with the flow of the gas containing zinc chloride. Here, in the second reactor 2, since a fine silicon crystal supplied from the first reactor 1 is used as a seed crystal to generate a large size silicon crystal, the reduction of silicon tetrachloride is performed. The reaction is more efficient, and the proportion of unreacted silicon tetrachloride, zinc, intermediates, and even fine silicon crystals decreases with respect to the gas containing by-product zinc chloride. Can be evaluated.

  The gas processing apparatus 3 includes an auxiliary reactor 60 that communicates with the second reactor 2 via the communication unit 50, and a gas processing unit 70 that is provided downstream of the auxiliary reactor 60. The auxiliary reactor 60 of the gas processing apparatus 3 is a straight tube and is erected in parallel with the z-axis in consideration of the possibility of the inflowing fine silicon crystal and unreacted gas. The structure is the same as that of the first reactor 1 and the second reactor 2 except that the silicon tetrachloride gas supply system 4 and the zinc gas supply system 5 are not communicated with each other. The same components are denoted by the same reference numerals, and the description thereof is omitted. In addition, since the gas flowing upward in the auxiliary reactor 60 can be evaluated as the residual reaction for reducing the silicon tetrachloride gas in the auxiliary reactor 60 is substantially completed, the by-product is substantially eliminated. It can be considered that the gas contains only typical zinc chloride. The pressure controller 35 that communicates with the first reactor 1 and the second reactor 2 may communicate with the auxiliary reactor 60 in the same manner. In such a case, the pressure in the auxiliary reactor 60 is detected. .

  Here, the gas processing unit 70 connected to the upper end (the positive direction of the z-axis) of the auxiliary reactor 60 of the gas processing device 3 performs a process of liquefying zinc chloride gas sent from the auxiliary reactor 60. . The gas processing unit 70 communicates with the upper end portion of the auxiliary reactor 60, and forms a straight tubular portion 71a inclined downward (in the negative direction of the z-axis) downstream, and a box-shaped portion 71b surrounding the periphery thereof. The air cooling condenser 71 is indirectly cooled by the hot air supplied from the hot air supply system 80, and liquefies the zinc chloride gas flowing therein. The warm air supplied to the air-cooled condenser 71 is supplied from the warm-air supply system 80 to the supply port 71 c provided in the box-shaped part 71 b of the air-cooled condenser 71 and passes around the straight tubular part 71 a of the air-cooled condenser 71. Thereafter, the air is discharged from a discharge port portion 71d provided in the box-shaped portion 71b of the air-cooled condenser 71, and the temperature thereof is set sufficiently lower than the boiling point of zinc chloride to cool the zinc chloride gas.

  Further, in the gas processing device 3, a zinc chloride tank 90 for collecting molten zinc chloride liquefied by the gas processing unit 70 communicates with the downstream of the gas processing unit 70 and below (in the negative direction of the z axis). The zinc chloride tank 90 has a load cell 91 for measuring the weight of molten zinc chloride accumulated therein. The zinc chloride tank 90 has a supply port portion 90a that communicates with the nitrogen gas supply system 95, and seals the downstream portion of the gas processing unit 70 to shut off the outside air. Further, the internal space is made of nitrogen gas. Replaced. The molten zinc chloride in the zinc chloride tank 90 is discharged and recovered from the zinc chloride discharge system 96, and the non-condensable gas in the zinc chloride tank 90 is discharged from the discharge port 90b.

  Specifically, as shown in FIG. 4, the hot air supply system 80 has an air line 81 that connects the supply port 71c and the discharge port 71d in the box-shaped portion 71b of the air-cooled condenser 71 and through which air flows. The air line 81 is provided with a blower fan 82 on the supply port 71c side and a cooler 83 on the discharge port 71d side. The blower fan 82 is controlled to rotate by the inverter device 84, and the cooler 83 is a constant temperature in which the temperature of the hot air in the air line 81 is detected by the temperature controller 85 while the temperature of the detected hot air is set. The amount of cooling is feedback controlled so that the temperature is reached. The cooling hot air supplied to the air-cooling condenser 70 is controlled to a constant temperature by the cooler 83 controlled by the temperature controller 85 while flowing through the air line 81, and then the rotation operation is controlled to a predetermined state by the inverter device 84. By being blown at a flow rate set by the blower fan 82, the air is supplied to the supply port 71 c of the air-cooled condenser 71, and after cooling the straight tubular portion 71 a of the air-cooled condenser 71, the discharge port of the air-cooled condenser 71. The air is discharged from 71 d and returned to the air line 81.

  Specifically, in the gas processing device 3, the inverter device 84 for the blower fan 82 that blows the warm air for cooling to the air-cooling condenser 71 in the gas processing unit 70 is made of molten zinc chloride stored in the zinc chloride tank 90. The rotation operation of the blower fan 82 is controlled based on the signal from the load cell 91 so that the change per unit time in the weight becomes constant. As a result, the cooling capacity (load) of the air-cooled condenser 71 for the zinc chloride gas is controlled, the amount of zinc chloride condensed in the air-cooled condenser 71 is controlled, and the corresponding reduction in the volume of zinc chloride gas received into the gas processing device 3 is achieved. As a result, not only the flow rate of the gas flowing through the gas processing device 3 but also the flow rate of the gas passing through the first reactor 1 and the second reactor 2 is controlled. . Such control is feedback control because it is control resulting from controlling the rotational operation of the blower fan 82 so that the change in the weight of the molten zinc chloride accumulated in the zinc chloride tank 90 is constant.

  Now, in order to continuously mass-produce solid silicon with a stable quality and a constant shape, the temperature in each reactor is set to a steady state so as to eliminate the temperature disturbance in each reactor, and each reactor is The flow rate of the gas passing therethrough is controlled to be in a steady state, and the supply amount of the raw material gas to each reactor is controlled so that the pressure in each reactor is in a steady state. It is necessary to stabilize the precipitation state.

  Here, the periphery of the auxiliary reactor 60 of the first reactor 1, the second reactor 2, and the gas processing device 3 is surrounded by a heater H, and the inside of these is externally set to a constant temperature of 1100 ° C. or higher. It is heated and controlled so that its temperature is maintained by a controller of the heater H.

  Under such conditions, first, the control set value of the supply amount of the raw material gas (silicon tetrachloride gas and zinc gas) to the first reactor 1 and the second reactor 2 is kept constant and stored in the zinc chloride tank 90. The change in the weight of the molten zinc chloride, that is, the control setting value of the weight of zinc chloride per unit time received in the zinc chloride tank 90 is controlled so that the pressure in the first reactor 1 and the second reactor 2 is constant. You may comprise.

  Specifically, the pressure in the first reactor 1 and the second reactor 2 is detected by the pressure controller 35 connected to each of the reactors 1 and 2, and the inverter device 84 corresponding to the pressure detection signal is used. A signal indicating the control set value is sent to the inverter device 84, and the inverter device 84 blows air under the pressure controller 35 so that the pressure in the first reactor 1 and the second reactor 2 is constant. The rotational operation of the fan 82 is cascade controlled to control the amount of decrease in the volume of zinc chloride gas received into the gas processing device 3 and the flow rate of the gas passing through the first reactor 1 and the second reactor 2. In addition, the pressure controller 35 calculates each pressure of the detected reactors 1 and 2 according to a predetermined calculation formula, obtains the pressure value of each reactor 1 and 2 as a whole, and sets a control set value corresponding to the calculated value. Seeking. In addition, when the pressure controller 35 also detects the pressure of the auxiliary reactor 60, the pressure value of each of the reactors 1, 2, 60 may be obtained in consideration of the pressure of the auxiliary reactor 60. .

  On the other hand, the control set value of the weight of zinc chloride per unit time received in the zinc chloride tank 90 is kept constant, and the raw material gases (silicon tetrachloride gas and zinc gas) are supplied to the first reactor 1 and the second reactor 2. You may comprise so that the control setting value of quantity may be controlled so that the pressure in the 1st reactor 1 and the 2nd reactor 2 may become fixed.

  Specifically, in the silicon tetrachloride gas introduction system 4, the flow rate controller 14 adjusts the opening degree of the valve 12 based on the flow rate detection signal of the flow rate detector 13 and flows through the supply line 11. The pressure in the first reactor 1 and the second reactor 2 is detected by a pressure controller 35 connected to each of the reactors 1 and 2 while controlling the gas flow rate to a predetermined flow rate. A signal indicating a control set value for the flow rate controller 14 corresponding to the detection signal is sent to the flow rate controller 14, and the flow rate controller 14 has a pressure in the first reactor 1 and the second reactor 2 under the pressure controller 35. Cascade control is performed to adjust the opening of the valve 12 so that becomes constant. Here, the pressure controller 35 calculates the detected pressures of the reactors 1 and 2 according to a predetermined arithmetic expression to obtain the pressure values of the reactors 1 and 2 as a whole, and the control set value corresponding to the calculated value. Seeking. In addition, the pressure value of each of the reactors 1, 2, 60 may be obtained in consideration of the pressure of the auxiliary reactor 60. This control is the same in the second reactor 2.

  In addition to the control of the silicon tetrachloride gas introduction system 4, in the zinc gas supply system 5, the feeder controller 22 b supplies the silicon tetrachloride gas supplied to the first reactor 1 and the first reactor 1. The feeder controller 22b controls the rotating operation of the rotating sphere 22a so as to maintain a quantitative relationship such that the molar ratio of zinc to silicon tetrachloride is 2 between the zinc gas and the zinc gas. While controlling the supply of liquid zinc fed from the zinc reservoir 14 at a predetermined flow rate, the feeder controller 22b keeps the pressure in the first reactor 1 and the second reactor 2 constant under the pressure controller 35. As described above, the rotation operation of the rotating sphere 22a is cascade controlled by proportional control linked to the control set value given to the flow rate controller 14 of the silicon tetrachloride gas introduction system 4. This control is the same in the second reactor 2.

  In this way, in addition to the normal feedback control, by performing cascade control that gives a control set value to this feedback control, the first reactor 1 and the second reactor 2, and thus the auxiliary reactor of the gas processing device 3. While maintaining the temperature in the reactor 60 at a constant level, the flow rate of the gas passing through the first reactor 1 and the second reactor 2 and reaching the gas processing device 3 is controlled, and the first reactor 1 and the second reactor 2 are controlled. By controlling the pressure in the reactor 2 and thus in the auxiliary reactor 60 of the gas treatment device 3 to be constant, the first reactor 1 not only continuously produces solid silicon with a stable quality and a fixed shape. In the second reactor 2, it is possible to produce a large-sized silicon crystal using the fine silicon crystal supplied from the first reactor 1 as a seed crystal, and a solid having a stable quality and a constant shape. Silico The yield well to continuous mass production. In addition, from the auxiliary reactor 60, solid silicon having a constant shape can be obtained with a stable quality.

(Second Embodiment)
Next, a silicon manufacturing apparatus according to the second embodiment of the present invention will be described in detail with reference to FIG.

  FIG. 5 is a schematic configuration diagram of a nitrogen gas supply system in the present embodiment.

  The silicon manufacturing apparatus S2 of this embodiment is mainly different from the silicon manufacturing apparatus 1 of the first embodiment in that the gas processing apparatus 3 is changed to a gas processing apparatus 100, and the first reactor The remaining configuration of the second reactor and the like is the same. Therefore, in the present embodiment, description will be made by paying attention to such differences, and the same components will be denoted by the same reference numerals, and description thereof will be simplified or omitted as appropriate.

  As shown in FIG. 5, the gas processing apparatus 100 in the silicon production apparatus S <b> 2 of this embodiment is provided downstream of the auxiliary reactor 60 and the auxiliary reactor 60 that communicates with the second reactor 2 via the communication unit 50. Gas processing unit 110 provided. The configuration of the auxiliary reactor 60 of the gas processing apparatus 100 is the same as that of the first embodiment.

  Here, the gas processing unit 110 connected to the upper end (positive direction of the z-axis) in the auxiliary reactor 60 of the gas processing apparatus 100 performs a process of solidifying the zinc chloride gas sent from the auxiliary reactor 60. . The gas processing unit 110 communicates with the upper end portion of the auxiliary reactor 60, and with respect to the reduced diameter portion 111a in the downstream portion of the straight tubular portion 111 that is inclined downward (in the negative direction of the z-axis) toward the downstream. The ejector 112 is provided. The ejector 112 has a nozzle portion 112a, is driven by nitrogen gas supplied from the nitrogen gas supply system 120 to the nozzle portion 112a, and has a straight tubular shape due to negative pressure generated in the vicinity of the end portion 112b of the nozzle portion 112a. The zinc chloride gas flowing through the part 111 is sucked and solidified. Here, the straight tubular portion 111 is asymptotically reduced in diameter toward the reduced diameter portion 111a in the downstream portion, and then expanded. Further, the end portion 112b of the nozzle portion 112a is positioned on the upstream side so as to face the reduced diameter portion 111a of the straight tubular portion 111. The heater H is provided so as to surround the straight tubular portion 111 located upstream of the ejector 112, and heats the straight tubular portion 111.

  Further, in the gas processing apparatus 100, a zinc chloride hopper 130 for collecting solid zinc chloride solidified by the gas processing unit 110 communicates downstream (downward direction of the z axis) of the gas processing unit 110. The zinc chloride hopper 130 has a load cell 131 that measures the weight of solid zinc chloride stored therein. The zinc chloride hopper 130 is blocked from outside air by replacing its internal space with nitrogen gas supplied from the nitrogen gas supply system 120 via the ejector 112. The solid zinc chloride in the zinc chloride hopper 130 is discharged and recovered from the zinc chloride discharge system 135 communicating with the zinc chloride hopper 130, and the non-condensable gas in the zinc chloride hopper 130 is in contact with the zinc chloride hopper 130. It is discharged from the outlet 137a through 137.

  The nitrogen gas supply system 120 includes a supply line 121 that connects the nitrogen gas supply source 140 and the nozzle portion 112a of the ejector 112 in the gas processing unit 110, and a valve 122 provided in the supply line 121, and further includes a supply line. 121, a flow rate detector 123 is provided downstream of the valve 122 (in the direction from the nitrogen gas supply source 140 toward the nozzle portion 112 a). The flow rate detector 123 detects the flow rate of the silicon tetrachloride gas flowing through the supply line 121. To do.

  The flow rate detection signal of the flow rate detector 123 is sent to the flow rate controller 124, and the flow rate controller 124 adjusts the opening degree of the valve 122 based on the input flow rate detection signal and flows through the supply line 121. The flow rate of silicon gas is controlled to a set flow rate. That is, the flow rate controller 124 controls the flow rate to a predetermined flow rate while monitoring the flow rate of the silicon tetrachloride gas flowing through the supply line 11, and the high-pressure nitrogen gas thus controlled to the predetermined flow rate is It is supplied to the nozzle portion 112a of the ejector 112 and ejected from the nozzle portion 112a.

  Specifically, in the gas processing apparatus 100, the flow rate controller 124 that controls the flow rate of the nitrogen gas supplied to the nozzle portion 112 a of the ejector 112 in the gas processing unit 110 includes the solid zinc chloride stored in the zinc chloride hopper 130. The opening degree of the valve 122 is controlled based on the signal from the load cell 131 so that the change per unit time in the weight becomes constant. As a result, the suction capacity (load) of the ejector 112 is controlled, the amount of solidified zinc chloride in the ejector 112 is controlled, and the amount of decrease in the volume of zinc chloride gas received into the gas processing apparatus 100 is controlled accordingly. As a result, not only the flow rate of the gas flowing through the gas processing apparatus 100 but also the flow rate of the gas passing through the first reactor 1 and the second reactor 2 is controlled. This control is feedback control because it is a control resulting from controlling the opening degree of the valve 122 so that the change in the weight of the solid zinc chloride accumulated in the zinc chloride hopper 130 is constant.

  Also in this embodiment, in order to continuously mass-produce solid silicon with a constant quality and a constant shape, the temperature in each reactor is set to a steady state so as to eliminate the temperature disturbance in each reactor. Thus, the gas flow rate passing through each reactor is controlled to be in a steady state, and the supply amount of the raw material gas to each reactor is controlled so that the pressure in each reactor is in a steady state. As in the first embodiment, it is necessary to stabilize the solid silicon deposition state in the reactor.

  That is, also in this embodiment, the circumference | surroundings of the 1st reactor 1 and the 2nd reactor 2, and the auxiliary reactor 60 of the gas processing apparatus 3, and the straight tubular part 111 are enclosed by the heater H, and these inside is 1100. Heating is performed from the outside so as to be a constant temperature of not lower than ° C., and the temperature is controlled by a controller included in the heater H.

  Under such conditions, first, the control set value of the supply amount of the raw material gas (silicon tetrachloride gas and zinc gas) to the first reactor 1 and the second reactor 2 is kept constant and accumulated in the zinc chloride hopper 130. The change in the weight of the solid zinc chloride, that is, the control set value of the weight of the solid zinc chloride per unit time received in the zinc chloride hopper 130 is set so that the pressure in the first reactor 1 and the second reactor 2 becomes constant. You may comprise so that it may be controlled.

  Specifically, in the gas treatment device 110, the flow rate controller 124 feedback-controls the opening degree of the valve 122 so that the change in the weight of the solid zinc chloride accumulated in the zinc chloride hopper 130 is constant, and the gas The first reactor 1 and the second reactor 2 are controlled while controlling the decrease in the volume of the zinc chloride gas received into the processing apparatus 100 and the flow rate of the gas passing through the first reactor 1 and the second reactor 2. Is detected by a pressure controller 35 provided in each of the reactors 1 and 2, and a signal indicating a control set value for the flow rate controller 124 corresponding to the pressure detection signal is sent to the flow rate controller 124. The controller 124 adjusts the degree of opening of the valve 122 under the pressure controller 35 so that the pressure in the first reactor 1 and the second reactor 2 is constant. Controlled and to control the flow rate of the gas passing through the reduction or the first reactor 1 and second reactor 2 receiving the gas volume of the zinc chloride gas into the gas treatment device 110. In addition, the pressure controller 35 calculates each pressure of the detected reactors 1 and 2 according to a predetermined calculation formula, obtains the pressure value of each reactor 1 and 2 as a whole, and sets a control set value corresponding to the calculated value. Seeking. In addition, the pressure value of each of the reactors 1, 2, 60 may be obtained in consideration of the pressure of the auxiliary reactor 60.

  On the other hand, also in the present embodiment, as in the first embodiment, the control set value of the weight of zinc chloride per unit time received in the zinc chloride tank 90 is kept constant, and the first reactor 1 and the second reactor The supply amount of the source gas (silicon tetrachloride gas and zinc gas) to 2 may be controlled so that the pressure in the first reactor 1 and the second reactor 2 is constant. .

  As described above, also in this embodiment, in addition to the normal feedback control, by performing the cascade control that gives the control setting value to the feedback control, the first reactor 1 and the second reactor 2, and thus the gas treatment. While maintaining the temperature in the auxiliary reactor 60 of the apparatus 100 constant, the flow rate of the gas passing through the first reactor 1 and the second reactor 2 and reaching the gas processing apparatus 100 is controlled to be constant. If the pressure in the first reactor 1 and the second reactor 2 and thus the pressure in the auxiliary reactor 60 of the gas processing apparatus 100 are controlled to be constant, solid silicon having a stable quality and a constant shape can be continuously produced. First, in the second reactor 2, it is possible to generate a silicon crystal of a large size by using the fine silicon crystal supplied from the first reactor 1 as a seed crystal, and the stable quality can be obtained. The shape of the solid silicon yield may be continuously mass-produced. In addition, from the auxiliary reactor 60, solid silicon having a constant shape can be obtained with a stable quality.

  In each of the embodiments described above, the configuration having two reactors, the first reactor and the second reactor, upstream of the gas processing apparatus has been described. Of course, the number of reactors is limited to two. It is possible to provide three or more reactors depending on the yield of solid silicon to be manufactured.

  In each of the above embodiments, the devices having control functions such as a flow rate controller, a feeder controller, an inverter device, and a pressure controller have been described as separate units. Of course, these are integrated and integrated as a controller. You can configure it.

  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, in order to avoid silicon deposition on the reactor wall surface and the like, and minimize the amount of silicon that is discharged together with the gas discharged from the reactor and is not recovered and the amount of unreacted raw material gas loss. In addition, the zinc reduction method that can stabilize the temperature distribution, raw material gas concentration distribution, and gas flow velocity distribution in the reactor to continuously mass-produce solid silicon of constant quality and shape and can operate at a high temperature of 1100 ° C or higher. It is expected that it can be widely applied to a manufacturing apparatus for silicon for solar cells and the like because of its general-purpose universal character.

It is a typical lineblock diagram of the silicon manufacture device in a 1st embodiment of the present invention. It is a typical block diagram of the silicon tetrachloride gas supply system in this embodiment. It is a typical block diagram of the zinc gas supply system in this embodiment. It is a typical lineblock diagram of the warm air supply system in this embodiment. It is a typical block diagram of the nitrogen gas supply system of the silicon manufacturing apparatus in the 2nd Embodiment of this invention.

Explanation of symbols

S1 …… Silicone production apparatus 1 ………… First reactor 1a …… Induction heating zone 2 ………… Second reactor 2a …… Induction heating zone 3 ……… Gas treatment device H ……… External heater 4 …… ... Silicon tetrachloride gas supply system 4a ... Supply port 5 ......... Zinc gas supply system 5a ... Supply port C ......... Cooling device 10 ... Silicon tetrachloride gas supply source 11 ... Supply line 12 ... Valve 13 …… Flow detector 14 …… Flow controller 20 …… Liquid zinc supply source 21 …… Liquid zinc reservoir 22 …… Quantity feeder 22a… Rotating ball 22b… Feeder controller 23 …… Zinc heater 23a… Heater 24 …… Vapor separator 25 ... Mist separator Ha ... Induction heater 30 ... Crystal discharge device 30a ... Housing 30b ... Rotating ball 31 ... Argon gas supply system 31a ... Supply port 32 ... Al Gas supply system 32a ... Supply port 33 ... Solid silicon discharge system 35 ... Pressure controller 40 ... Communication part 50 ... Communication part 60 ... Auxiliary reactor 70 ... Gas treatment part 71 ... Air-cooled condenser 71a ... Direct Tubular portion 71b ... Box-shaped portion 71c ... Supply port portion 71d ... Discharge port portion 80 ... Warm air supply system 81 ... Air line 82 ... Blower fan 83 ... Heater 84 ... Inverter device 85 ... Temperature controller 90 ... ... Zinc chloride tank 90a ... Supply port 90b ... Discharge port 91 ... Load cell 95 ... Nitrogen gas supply system 96 ... Zinc chloride discharge system S2 ... Silicon production apparatus 100 ... Gas treatment apparatus 110 ... Gas treatment section 111 ... Straight tubular portion 111a ... Diameter reducing portion 112 ... Ejector 112a ... Nozzle portion 112b ... End portion 120 ... Nitrogen gas supply system 121 ... Supply line 12 ... Valve 123 ... flow detector 124 ... flow controller 130 ... zinc zinc chloride hoppers 131 ... load cell 135 ... chloride efflux system 137 ... bag filter 137a ... outlet portion 140 ... the nitrogen gas supply source

Claims (15)

A first reactor;
A first silicon compound gas supply system which communicates with the first reactor and supplies silicon compound gas into the first reactor;
A first zinc gas supply system that communicates with the first reactor and supplies zinc gas into the first reactor;
A second reactor communicated by a first communication section downstream of the first reactor;
A second silicon compound gas supply system that communicates with the second reactor and supplies silicon compound gas into the second reactor;
A second zinc gas supply system that communicates with the second reactor and supplies zinc gas into the second reactor.
The first reactor reduces a silicon compound contained in the silicon compound gas supplied by the first silicon compound gas supply system with zinc contained in the zinc gas supplied by the first zinc gas supply system. The second reactor is a reactor that generates solid silicon, and the second reactor flows into the second reactor through the first connecting portion among the solid silicon generated in the first reactor. The zinc gas supplied from the second zinc gas supply system to a silicon compound contained in the silicon compound gas supplied from the second silicon compound gas supply system while using solid silicon having a relatively small crystal size as a seed crystal. The silicon production equipment which is a reactor which produces | generates solid silicon by reducing with zinc contained in.   The said 1st reactor and the said 2nd reactor each are equipped with the induction heating apparatus which heats the said solid silicon inside each of the said 1st reactor and the said 2nd reactor to near melting | fusing point. The silicon manufacturing apparatus as described.   The first silicon compound gas supply system and the first zinc gas supply system are controlled to supply the silicon compound gas and the zinc gas to the first reactor at a predetermined flow rate while maintaining a relationship of a predetermined molar ratio. The second silicon compound gas supply system and the second zinc gas supply system maintain the silicon compound gas and the zinc gas in a predetermined molar ratio with respect to the second reactor while maintaining a predetermined flow rate. The silicon manufacturing apparatus according to claim 1, wherein the silicon manufacturing apparatus is a control system that is supplied with   The first silicon compound gas supply system and the second silicon compound gas supply system include a gas supply source for supplying a silicon compound gas to a supply line, a valve capable of opening and closing the supply line, and the silicon flowing through the supply line. A flow rate detector for detecting a flow rate of the compound gas, and a flow rate controller for controlling the flow rate of the silicon compound gas flowing through the supply line via the valve based on a detection result of the flow rate detector. Item 4. The silicon manufacturing apparatus according to Item 3.   The first zinc gas supply system and the second zinc gas supply system have a liquid zinc supply source for supplying liquid zinc to a liquid zinc reservoir, and a rotating member formed with a non-through hole and rotatably held. And a quantitative feeder that feeds the liquid zinc while controlling the flow rate of the liquid zinc fed from the liquid zinc reservoir by the rotation of the rotating member under the control of the feeder controller. The silicon manufacturing apparatus of Claim 3 or 4 which produces | generates zinc gas from the said liquid zinc liquefied.   Furthermore, a gas processing device communicated by a second communication unit downstream of the second reactor is provided, and the gas processing device is by-produced in the first reactor, which flows in through the second communication unit. A processing apparatus for receiving a zinc compound gas and a zinc compound gas by-produced in the second reactor by liquefying or solidifying and receiving the zinc compound gas, controlling the amount of decrease in the volume of the zinc compound gas received, and the first reactor and The silicon manufacturing apparatus according to claim 1, further comprising a control system capable of controlling a flow rate of the gas passing through the second reactor.   The gas processing apparatus includes an air cooling condenser that cools the inside thereof and a cooling medium supply system that supplies a cooling medium to the air cooling condenser. The cooling medium supply system is a control system that controls the cooling capacity of the air cooling condenser. The silicon manufacturing apparatus according to claim 6.   The cooling medium supply system includes an air line that communicates with the air-cooling condenser, a cooler that maintains air flowing through the air line at a constant temperature, and the air that is maintained at the constant temperature flowing through the air line. The silicon manufacturing apparatus according to claim 7, further comprising: a blower fan that blows air to the air-cooled condenser through a transmission; and a transmission that controls a rotation operation of the blower fan.   The gas treatment device further includes a zinc compound tank that receives the molten zinc compound liquefied by the air-cooled condenser, and a load cell that measures the weight of the molten zinc compound accumulated in the zinc compound tank, The silicon manufacturing apparatus according to claim 8, wherein the apparatus controls the rotation operation of the blower fan so that the amount of change in the weight of the molten zinc compound measured by the load cell is constant.   The gas processing apparatus includes an ejector that generates a negative pressure therein and an ejection medium supply system that supplies an ejection medium to the ejector, and the ejection medium supply system is a control system that controls a cooling capacity of the ejector. The silicon manufacturing apparatus according to claim 6.   The ejection medium supply system includes: an ejection medium supply source that supplies the ejection medium to a supply line; a valve that can open and close the supply line; a flow rate detector that detects a flow rate of the ejection medium flowing through the supply line; The silicon manufacturing apparatus according to claim 10, further comprising: a flow rate controller that controls a flow rate of the ejection medium flowing through the supply line via the valve based on a detection result of the flow rate detector.   The gas processing apparatus further includes a zinc compound hopper that receives the solid zinc compound solidified by the ejector, and a load cell that measures the weight of the solid zinc compound accumulated in the zinc compound hopper, and the flow controller The silicon manufacturing apparatus according to claim 11, wherein the opening degree of the valve is controlled so that a change amount of the weight of the solid zinc compound measured by the load cell is constant.   The gas processing apparatus includes an auxiliary reactor, and the auxiliary reactor uses the solid silicon having a relatively small crystal size that has flowed into the auxiliary reactor through the second communication portion as a seed crystal. The silicon production apparatus according to any one of claims 4 to 12, which is a reactor capable of generating solid silicon using an unreacted gas that has passed through a second communication portion and has flowed into the auxiliary reactor.   Furthermore, a heater that keeps the temperature inside the first reactor and the second reactor constant, and a controller that controls the pressure inside the first reactor and the second reactor to a constant pressure, The controller includes the control system of the first silicon compound gas supply system and the first zinc gas supply system so as to control the inside of the first reactor and the second reactor to the constant pressure, The silicon manufacturing apparatus according to claim 3, wherein the control system of the second silicon compound gas supply system and the second zinc gas supply system or the control system of the gas processing apparatus is controlled.   The silicon compound gas supplied from the first silicon compound gas supply system to the first reactor is supplied upstream of the zinc gas supplied from the first zinc gas supply system, and the first reactor 2. The two-reactor, wherein the silicon compound gas supplied from the second silicon compound gas supply system is supplied upstream of the zinc gas supplied from the second zinc gas supply system. The silicon manufacturing apparatus in any one of 14 thru | or 14.

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