JP2008143756A - Method of manufacturing high purity silicon and apparatus for manufacturing high purity silicon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a high purity silicon and an apparatus for manufacturing the high purity silicon capable of reducing the manufacturing cost and stably mass-producing the high purity silicon. <P>SOLUTION: An arc plasma jet generating apparatus 11 has a jet generating part 21 for generating plasma jet, a silicon gas supply part 23 for supplying a fluorine-based silicon gas (SiF<SB>4</SB>) or silane gas (SiH<SB>4</SB>) to the plasma jet generated in the jet generating part 21, and a jetting port 21b for jetting the plasma jet to the outside. A diffusion suppressing means 12 is provided extending from the jetting port 21b in the jetting direction so as to suppress the diffusion of the plasma jet. A capturing means 14 is provided in front of the diffusion suppressing means 12 in the jetting direction so as to capture silicon produced by decomposition of the fluorine-based silicon gas or the silane gas from the plasma jet passing through the diffusion suppressing means 12. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a high-purity silicon manufacturing method and a high-purity silicon manufacturing apparatus capable of mass-producing high-purity silicon at low cost.

  The demand for high-purity silicon is increasing year by year due to the increase in solar cell production. Until now, the company has mainly produced non-standard products for silicon for semiconductors, but the market of the semiconductor industry has changed despite the increase in solar cell production year by year. The actual situation is that the amount of non-standard products generated is not stable.

  Since silicon used for solar cells does not have to be as pure as silicon for semiconductors, research on the production of silicon for solar cells has been conducted in recent years, and various production methods have been proposed. For example, the mainstream method is to produce high-purity silicon from an inexpensive metal silicon raw material by a metallurgical refining process at a high temperature for a long time. There is a demand for lower costs.

  As a conventional method for producing silicon for solar cells, metal silicon raw materials are subjected to vacuum refining and purification by unidirectional solidification to remove impurity elements such as phosphorus, calcium, aluminum, iron, titanium and the like for solar cells. There is a method for producing high-purity silicon (see, for example, Patent Document 1). This high-purity silicon manufacturing method is an energy consuming process that requires a metallurgical process many times, and thus has a problem that the manufacturing cost increases.

The present inventors have previously proposed an invention for producing high-purity silicon using plasma CVD technology. The present invention, reducing the pressure in the rotation chamber made of quartz, and generates a plasma region by the power-on from the coil in a hydrogen-argon atmosphere containing SiF ₄ or SiH _4, decomposing SiF ₄ or SiH ₄ in plasma At the same time, the Si fine powder seed crystal introduced into the chamber by the rotation of the chamber is lifted up by the weir and freely dropped in the plasma region, and the silicon produced by the decomposition of SiF ₄ or SiH ₄ is converted into the Si fine powder seed crystal. This is a method and apparatus for depositing on the surface by homoepitaxial growth (see Patent Document 2).

This invention is characterized by high purity of silicon produced by using plasma CVD reaction and using SiF ₄ or SiH ₄ in a gas state containing no impurities as a starting material. However, on the other hand, pressure reduction conditions of about 0.01 MPa are necessary, and when the production scale is increased in order to increase the production amount, there is a cost problem that the pressure reduction equipment cost further increases. In addition, since the chamber is rotated, there is a risk of air leaking from the vacuum seal of the rotating mechanism, so there is a risk of silicon oxidation, and the yield of the plasma becoming unstable due to pressure fluctuations due to air leaks. There has been a significant problem in yield, that is, a decrease in yield and a decrease in yield due to a reaction in which silicon produced by decomposition returns to SiF ₄ during cooling.

  This was thought to be due to the low plasma density, so we designed, produced, and studied a coaxial magnetron plasma device that can suppress the decrease in plasma density by constraining the generated plasma by a magnetic field. The internal structure of the coaxial magnetron type plasma apparatus is shown in FIG. Basically, it is a capacitively coupled plasma device consisting of an internal electrode and an external electrode, but it has a structure in which a large number of magnetron magnetic fields are formed by a magnet housed in the internal electrode and plasma is generated over the entire length of the chamber. ing. However, the coaxial magnetron type plasma apparatus shown in FIG. 8 was examined under the conditions shown in Table 1, but although the yield was improved, it was found that further improvement was necessary.

  In the conventional plasma spraying technique, an arc plasma jet is used for repairing a metal surface, and a radio frequency (RF) plasma jet is used for forming a silicon thin film such as a lithium battery or a solar battery (for example, patents). Reference 3 or 4).

Japanese Patent Laid-Open No. 10-245216 Japanese translation of PCT publication No. 2004-525841 Japanese Patent No. 3702223 JP-A-56-125882

  As a result of intensive investigations on the manufacturing technology capable of mass-producing high-purity silicon at low cost from the same fluorine-based silicon gas or silane gas as the raw material used in the invention described in Patent Document 2 and the examination by the coaxial magnetron plasma apparatus, the present inventors In comparison with plasma CVD technology and coaxial magnetron type plasma technology, it has come to focus on plasma spraying technology, which has less restrictions on facilities and is inexpensive in terms of manufacturing cost. There has been no example of using the plasma jet used for this plasma spraying for mass production of high-purity silicon.

  According to experiments by the present inventors, it has been found that an arc plasma jet having a high ionization degree is more suitable than a radio frequency (RF) plasma jet as a plasma jet for mass production of high-purity silicon. Repeated experiments to produce high-purity silicon from fluorine-based silicon gas using a plasma jet. Even if the arc plasma jet is sprayed in the same way as in the case of thermal spraying, the silicon yield is extremely low and mass production is achieved. A new problem has been found that is difficult.

  This is because (1) the arc plasma jet has a tendency to diffuse in all directions when exiting the injection port, so the length of the injection direction (longitudinal direction) of the high temperature region inside the plasma jet is short, and this diffused plasma Since the peripheral edge of the jet is rapidly cooled, the high-temperature region in the width direction is also narrow, so that a sufficient high-temperature region necessary for decomposition of the source gas cannot be secured inside the arc plasma jet. (2) In the arc plasma jet The supplied source gas is also easily diffused in all directions, and part of it is dissipated to the outside of the plasma jet, resulting in a large source loss. (3) Since the source gas diffuses inside the plasma jet, it decomposes in the high temperature region. It is thought that the decrease in the density of the active species is a factor that makes the silicon yield extremely low.

  The present invention has been made paying attention to the problems associated with such arc plasma jets, and is capable of stably mass-producing high-purity silicon and reducing the manufacturing cost, and a high-purity silicon manufacturing method. An object of the present invention is to provide a purity silicon manufacturing apparatus.

  In order to solve the above-mentioned problems of the arc plasma jet, the present inventors need to suppress the diffusion of the arc plasma jet and the raw material gas in all directions, and use the arc plasma jet that is jetted at a high speed. In this case, it has been found that it is necessary to lengthen the high temperature region in the injection direction inside the arc plasma jet to sufficiently secure the residence time required for the decomposition of the raw material gas. The present invention is characterized in that all of the above problems are solved at the same time by a simple means of passing the arc plasma jet through a diffusion suppressing means such as a pipe, whereby high yield and relatively low cost. In addition, high-purity silicon can be mass-produced.

  The high-purity silicon manufacturing method according to the present invention generates an arc plasma jet, supplies a fluorine-based silicon gas or a silane gas to the arc plasma jet, passes the arc plasma jet through diffusion suppressing means, In which the fluorine-based silicon gas or the silane gas is decomposed to generate silicon, and the silicon is collected from the arc plasma jet.

  A high-purity silicon production apparatus according to the present invention includes an arc plasma jet generation device, a diffusion suppression unit, and a silicon collection unit. The arc plasma jet generation device includes a jet generation unit that generates an arc plasma jet; A silicon gas supply unit that supplies a fluorine-based silicon gas or a silane gas to the arc plasma jet generated by the jet generation unit; and an injection port that injects the arc plasma jet to the outside. Extending in the injection direction from the injection port so as to suppress diffusion of the arc plasma jet, and the collecting means is obtained by decomposing the fluorine-based silicon gas or the silane gas from the arc plasma jet that has passed through the diffusion suppression means. The injection method of the diffusion suppressing means to collect the generated silicon That is provided in front of, and features.

The high-purity silicon manufacturing method and high-purity silicon manufacturing apparatus according to the present invention combine high-purity silicon by combining standard arc plasma technology, which has less restrictions on facilities than plasma CVD, and simple diffusion suppression means. Since it can be stably mass-produced with a high yield, the manufacturing cost can be reduced. Note that the fluorine-based silicon gas or silane gas as the source gas is specifically SiF ₄ or SiH ₄ .

  In the high-purity silicon manufacturing method according to the present invention, it is preferable that the diffusion suppressing means is set so that a transit time of the arc plasma jet is 11 msec or more. In the high-purity silicon manufacturing apparatus according to the present invention, it is preferable that the diffusion suppressing means is set so that a transit time of the arc plasma jet is 11 msec or more. When the transit time is as short as less than 11 msec, the residence time in the high temperature region necessary for decomposing the fluorine-based silicon gas or silane gas in the arc plasma jet cannot be sufficiently secured in the diffusion suppressing means, and the source gas Since the decomposition of silicon becomes insufficient, the yield of silicon decreases. Therefore, in order to sufficiently decompose the source gas and increase the yield of silicon, it is preferable to set the passage time of the arc plasma jet to at least 11 msec. However, even if the transit time is longer than 111 msec, no significant improvement in the silicon yield is observed any more. Therefore, it is more preferable to set the range from 11 msec to 111 msec.

  In the high-purity silicon manufacturing method and manufacturing apparatus according to the present invention, the diffusion suppressing means may have a cylindrical shape. The diffusion suppressing means is preferably a simple means such as a metal pipe made of water-cooled copper or SUS or a pipe made of silicon, for example, in terms of manufacturing cost. However, it is not limited to the cylindrical shape as long as the diffusion of the arc plasma jet can be suppressed. In the case of a water-cooled copper pipe, the diameter may be about 10 to 500 mm, which is the injection diameter of a standard plasma apparatus.

  The high purity silicon manufacturing method and manufacturing apparatus according to the present invention may generate a magnetic field around the diffusion suppressing means. In this case, a magnetic field generating means is provided around the diffusion suppressing means such as a copper pipe, and the arc plasma is confined in the generated magnetic field to improve the resolution of the arc plasma, and the silicon yield can be further improved.

  In the high-purity silicon manufacturing method according to the present invention, the arc plasma jet may be sprayed toward the inside of the chamber, and the silicon may be collected inside the chamber. The inside of the chamber is preferably an inert gas atmosphere or a vacuum atmosphere. The high-purity silicon manufacturing apparatus according to the present invention has a chamber in which the arc plasma jet is injected, the chamber is an inert gas atmosphere or a vacuum atmosphere, and the collecting means is disposed inside the chamber. May be. If the collecting means is disposed inside the chamber, silicon can be easily collected without waste.

In the present invention, since the arc plasma jet is passed through the diffusion suppressing means to suppress the diffusion of the arc plasma jet, it is possible to suppress the decrease in the density of the decomposition active species of the fluorine-based silicon gas or the silane gas and to suppress the decrease in the plasma temperature. . Further, since the high temperature region in the injection direction necessary for decomposing the fluorine-based silicon gas or silane gas in the diffusion suppressing means can be lengthened, the residence time required for the decomposition of the raw material gas can be sufficiently ensured. The loss (undecomposition) can be avoided and almost the entire amount can be decomposed, and high-purity silicon can be stably mass-produced at a high yield. For this reason, the manufacturing cost can also be reduced. Further, in the present invention, since the silicon decomposed in the arc plasma jet is jet-jetted out of the diffusion suppressing means and instantaneously cooled, the return reaction that occurs in the plasma CVD technique, that is, once decomposed silicon Since the reaction of returning to SiF ₄ during cooling can be avoided, high-purity silicon can be mass-produced stably and with a higher yield than the plasma CVD technique.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3, 5, and 7 show a high-purity silicon manufacturing method and a high-purity silicon manufacturing apparatus according to an embodiment of the present invention.
As shown in FIGS. 1 and 2, the high-purity silicon manufacturing apparatus 10 includes an arc plasma jet generator 11, a diffusion suppressing unit 12, a chamber 13, and a collecting unit 14.

  As shown in FIG. 1A, the arc plasma jet generator 11 includes a jet generation unit 21, an arc gas introduction unit 22, a silicon gas supply unit 23, and a cooling water circulation unit 24. The jet generator 21 is formed by forming an elongated arc plasma generation space 21 a having a depth about half the length of the arc plasma jet generator 11 at the center of one end face 11 a of the arc plasma jet generator 11. Yes. In the jet generator 21, the opening of the arc plasma generation space 21a located on one end surface 11a of the arc plasma jet generator 11 forms a circular injection port 21b. The jet generation unit 21 has a cathode 21c extending toward the injection port 21b at the center of the bottom of the arc plasma generation space 21a. The jet generator 21 has an anode 21d on the inner wall of the arc plasma generation space 21a slightly inside the injection port 21b.

The arc gas introduction part 22 includes an arc connection part 22a protruding perpendicularly to the end face 11b from the other end face 11b of the arc plasma jet generator 11, and an arc opening part 22b provided at the tip of the arc connection part 22a. And an arc introduction path 22c provided to communicate the arc opening 22b with the arc plasma generation space 21a. The arc gas introduction part 22 can supply arc gas for generating arc plasma supplied from the arc opening part 22b to the arc plasma generation space 21a through the arc introduction path 22c. As a result, the jet generator 21 generates an arc between the cathode 21c and the anode 21d in the arc plasma generation space 21a of the arc gas atmosphere, converts the arc gas into plasma, and injects the arc plasma jet to the outside from the injection port 21b. It is possible. Note that the gas used here is an inert gas such as argon (Ar) or a mixed gas of an inert gas and hydrogen (H ₂ ).

The silicon gas supply unit 23 includes a silicon gas supply port 23a provided on the side surface 11c on one end side of the arc plasma jet generator 11, and a silicon gas provided on the inner wall of the arc plasma generation space 21a slightly inside the injection port 21b. An introduction port 23b and a silicon gas introduction path 23c that communicates the silicon gas supply port 23a and the silicon gas introduction port 23b are provided. The silicon gas supply unit 23 can supply the gas mixture of SiF ₄ and hydrogen (H ₂ ) supplied from the silicon gas supply port 23a to the arc plasma generation space 21a from the silicon gas introduction port 23b through the silicon gas introduction path 23c. It has become. Accordingly, the silicon gas supply unit 23 can supply SiF ₄ to the arc plasma jet generated by the jet generation unit 21.

  The cooling water circulation unit 24 protrudes perpendicularly to the end surface 11c from the center of the cooling water supply port 24a provided on the side surface 11c of the arc plasma jet generating device 11 and the other end surface 11b of the arc plasma jet generating device 11. The cooling water connection portion 24b, the cooling water drain port 24c provided at the tip of the cooling water connection portion 24b, and the cooling water supply port 24a and the cooling water drain port 24c communicate with each other around the arc plasma generation space 21a. A cooling water circulation path 24d. The cooling water circulation unit 24 can discharge the cooling water supplied from the cooling water supply port 24a from the cooling water drain port 24c through the cooling water circulation path 24d. Thereby, the cooling water circulation part 24 can cool the arc plasma generation space 21a from the outside by the cooling water.

  As shown in FIG. 1B, the diffusion suppressing means 12 is made of a water-cooled metal pipe, and is attached to one end surface 11a of the arc plasma jet generator 11 so that the inside 12a communicates with the injection port 21b. It has been. Further, the diffusion suppressing means 12 is attached so as to extend from the injection port 21b in the injection direction of the arc plasma jet, and suppresses the diffusion of the arc plasma jet.

  The diffusion suppressing means 12 cools around the periphery of the interior 12a, the cooling water inlet 12b provided at the end of the arc plasma jet generator 11 side, the cooling water outlet 12c provided at the same end. It has a cooling water passage 12d that allows the water introduction port 12b and the cooling water discharge port 12c to communicate with each other. The diffusion suppressing means 12 can discharge the cooling water supplied from the cooling water introduction port 12b from the cooling water discharge port 12c through the cooling water channel 12d. Thereby, the diffusion suppression means 12 can cool the inside 12a through which the arc plasma jet passes by cooling water from the outside.

  As shown in FIG. 2, the arc plasma jet generator 11 in which the diffusion suppressing means 12 is disposed is attached to one end of the interior 13a of the chamber 13. The chamber 13 is connected to a rotary pump 25 capable of discharging the air in the interior 13a, so that a vacuum atmosphere can be formed.

The collection means 14 includes a collection plate 26 and a cooling plate 27 that is attached to the back side of the collection plate 26 and cools the collection plate 26, and is disposed in the interior 13 a of the chamber 13. . The collection means 14 is arranged in front of the injection direction of the diffusion suppression means 12 with the collection plate 26 facing the arc plasma jet generator 11, and collects the arc plasma jet that has passed through the diffusion suppression means 12. It is received and cooled at 26, and silicon produced by the decomposition of SiF ₄ is deposited on the collecting plate 26 and can be collected.

In the high purity silicon manufacturing method according to the embodiment of the present invention, an arc gas is supplied to the arc plasma generation space 21 a by the arc gas introduction unit 22, and an arc plasma jet is generated by the jet generation unit 21. SiF ₄ or a mixed gas of SiF ₄ and hydrogen is supplied to the generated arc plasma jet by the silicon gas supply unit 23, and the arc plasma jet is injected from the injection port 21b. At this time, by supplying SiF ₄ to the generated arc plasma jet, SiF ₄ can be decomposed in the arc plasma jet to generate silicon.

As shown in FIG. 3, the injected arc plasma jet passes through the diffusion suppressing means 12 and is injected into the interior 13 a of the chamber 13. At this time, the diffusion suppressing means 12 can suppress the diffusion of the arc plasma jet. In addition, it suppresses the decrease in the density of the active decomposition species of SiF ₄ and suppresses the decrease in the temperature of the arc plasma, thereby extending the high temperature region in the injection direction inside the arc plasma jet and sufficiently securing the residence time required for the decomposition of the source gas. can do.

  The silicon decomposed by the arc plasma jet exits from the diffusion suppressing means 12 and is injected into the inside 13 a of the chamber 13, hits the collection plate 26, is cooled, and is deposited on the collection plate 26. By collecting this silicon, high purity silicon can be obtained. Thus, according to the high-purity silicon manufacturing method and the high-purity silicon manufacturing apparatus 10 of the embodiment of the present invention, high-purity silicon can be stably mass-produced with a high yield.

[Comparative test for confirming the effect of the diffusion suppressing means 12]
In order to confirm the effect of the diffusion suppression means 12, as shown in FIG. 4, the test was performed with the diffusion suppression means 12 removed. Table 2 shows the test conditions. As shown in FIG. 5, the arc plasma generator including the arc plasma jet generator 11 at this time is a standard apparatus used for plasma spraying such as surface treatment. Further, in order to generate and control arc plasma in the arc plasma jet generator 11, a gas control system for controlling the flow rate of arc gas, which is a source of arc plasma, and a current control system for controlling the arc current of the plasma are provided. Integrated controller 51, DC power supply 52 for supplying current to the plasma, cooling water supply device (Chiller 53 and Water Booster Pump 54) for cooling the arc plasma jet generator 11, cathode 21c and anode And a starter 55 for generating an arc between 21d and introducing an arc current. FIG. 5 shows a powder feeder (Roto Feeder) 56 for forming a sprayed coating used in the plasma spraying technique, but it is not used in this test.

  As a result of the test, in the state where the diffusion suppressing means 12 is removed, the test No. 1 and test no. In both cases, the yield of silicon was extremely low. Test No. In the case of test No. 1, test no. Although the silicon yield was low despite the fact that the input power amount was as large as 25 kw from FIG. 2, the present inventors paid attention to the diffusion of the plasma jet other than the power amount, and shown in FIGS. A test was conducted with the diffusion suppression means 12 shown.

[Relationship between length of diffusion suppressing means 12 and silicon yield]
Table 3 shows the tests when the water-cooled copper pipe with an inner diameter of 10.9 mm is not attached (length 0 mm) and when a copper pipe with a length of 100 to 1000 mm is attached to investigate the action and effect of the diffusion suppression means 12. The test was performed under the same conditions (other conditions such as voltage and current were constant). FIG. 6 illustrates the relationship between the silicon yield (%) and the length (mm) of the copper pipe.

As shown in FIG. 6, as a result of the test, it was confirmed that the silicon yield was remarkably improved when the diffusion suppressing means 12 was attached. This is because the diffusion suppression means 12 prevents the loss of the raw material gas and the temperature drop of the arc plasma jet, and can lengthen the high temperature region in the injection direction of the arc plasma jet. However, it is presumed that the source gas was sufficiently decomposed. It was also confirmed that the silicon yield improved in proportion to the length of the diffusion suppressing means 12 and dramatically improved when the length was at least 100 mm or more, particularly 300 mm or more. When the diffusion suppressing means 12 is 500 mm and 1000 mm, the silicon yield exceeds 95 wt%, but the silicon adhering to the cooling plate 27 and the inside 13 a of the chamber 13 cannot be completely recovered. In fact, it is estimated that the yield is very close to 100 wt%.
From the above results, it was confirmed that high-purity silicon can be stably mass-produced with a high yield by this simple means of diffusion suppression means 12.

Further, the length of the diffusion suppressing means 12 corresponds to the time required for SiF ₄ to be decomposed in the diffusion suppressing means 12, that is, the time during which the arc plasma jet and the source gas stay in the diffusion suppressing means 12. Therefore, when the length of the diffusion suppression means 12 is converted into the time for the arc plasma jet to pass through the diffusion suppression means 12 from the relationship with the arc gas flow rate, 11 msec when the length of the diffusion suppression means 12 is 100 mm. It can be expressed as 33 msec at 300 mm, 56 msec at 500 mm, and 111 msec at 1000 mm. Therefore, it can be said that the diffusion suppressing means 12 is preferably set so that the transit time of the arc plasma jet is at least 11 msec or more, more preferably 33 msec or more.

  FIG. 7 shows an outline in the case where the magnetic field generating means 51 is further provided around the diffusion suppressing means 12 of the present invention. In this case, the arc plasma is confined in the magnetic field and the density of the arc plasma is shown. And the resolution of the source gas of arc plasma can be further improved, which is effective for improving the silicon yield.

It is the longitudinal cross-sectional view which shows the (a) arc plasma jet generator of the high purity silicon manufacturing apparatus of embodiment of this invention, (b) The longitudinal cross-sectional view which shows an arc plasma jet generator and a diffusion suppression means. It is the front view which notched a part which shows the whole high purity silicon manufacturing apparatus shown in FIG. It is a longitudinal cross-sectional view which shows the use condition of the high purity silicon manufacturing apparatus shown in FIG. It is a longitudinal cross-sectional view which shows the state of the arc plasma jet of the arc plasma generator from which the diffusion suppression means was removed. 1 is an overall configuration diagram showing an arc plasma generation system including an arc plasma generation device. It is a graph which shows the relationship between the length of the diffusion suppression means of a high purity silicon manufacturing apparatus shown in FIG. 1, and a silicon yield. It is a longitudinal cross-sectional view which shows the modification which provided the magnetic field generation | occurrence | production means of the high purity silicon manufacturing apparatus shown in FIG. It is a longitudinal cross-sectional view which shows the internal structure of the conventional coaxial magnetron type | mold plasma apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 High-purity silicon manufacturing apparatus 11 Arc plasma jet generator 12 Diffusion suppression means 13 Chamber 14 Collection means 21 Jet generation part 21b Injection port 22 Arc gas introduction part 23 Silicon gas introduction part 24 Cooling water circulation part 26 Collection plate 27 Cooling plate

Claims (11)

Generate an arc plasma jet,
Fluorine-based silicon gas or silane gas is supplied to the arc plasma jet,
While passing the arc plasma jet through diffusion suppressing means, the fluorine plasma gas or the silane gas is decomposed in the arc plasma jet to generate silicon,
Collecting the silicon from the arc plasma jet;
A high-purity silicon manufacturing method characterized.   2. The high-purity silicon manufacturing method according to claim 1, wherein the diffusion suppressing means is set so that a transit time of the arc plasma jet is 11 msec or more.   The high-purity silicon manufacturing method according to claim 1, wherein the diffusion suppressing unit has a cylindrical shape.   4. A high-purity silicon manufacturing method according to claim 1, wherein a magnetic field is generated around the diffusion suppressing means. Injecting the arc plasma jet toward the inside of the chamber;
Collecting the silicon inside the chamber;
5. The method for producing high-purity silicon according to claim 1, 2, 3 or 4.   6. The high purity silicon manufacturing method according to claim 5, wherein the inside of the chamber is an inert gas atmosphere or a vacuum atmosphere. An arc plasma jet generator, a diffusion suppressing means, and a silicon collecting means;
The arc plasma jet generator includes a jet generator that generates an arc plasma jet, a silicon gas supply that supplies fluorine-based silicon gas or silane gas to the arc plasma jet generated by the jet generator, and the arc plasma An injection port for injecting the jet to the outside,
The diffusion suppressing means is provided extending in the injection direction from the injection port so as to suppress diffusion of the arc plasma jet,
The collection means is provided in front of the injection direction of the diffusion suppression means so as to collect silicon generated by decomposition of the fluorine-based silicon gas or the silane gas from the arc plasma jet that has passed through the diffusion suppression means. That
High-purity silicon production equipment.   8. The high-purity silicon manufacturing apparatus according to claim 7, wherein the diffusion suppressing means is set so that a transit time of the arc plasma jet is 11 msec or more.   The high-purity silicon manufacturing apparatus according to claim 7 or 8, wherein the diffusion suppressing means has a cylindrical shape.   10. The high-purity silicon manufacturing apparatus according to claim 7, 8 or 9, wherein a magnetic field generating means is provided around the diffusion suppressing means. A chamber in which the arc plasma jet is injected;
The inside of the chamber is an inert gas atmosphere or a vacuum atmosphere,
That the collecting means is disposed inside the chamber;
11. The high-purity silicon production apparatus according to claim 7, 8, 9 or 10.

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