KR20100002123A - Apparatus for producing polycrystalline silicon - Google Patents

Abstract

PURPOSE: An apparatus for producing polycrystalline silicon is provided to maintain good insulating property while absorbing heat of an electrode holder and a bottom plate part of a furnace, and to prevent damage of the electrode holder and the bottom plate part. CONSTITUTION: A furnace of an apparatus for producing polycrystalline silicon includes a bottom plate part(2) and a bell jar. The bottom plate part has a plurality of electrode units(5), a nozzle, and a gas outlet. The furnace has two electrode units. An electrode holder is inserted into a penetration hole(21) formed on the bottom plate part of the furnace. The electrode maintains a silicon core bar(4), and formed on the top of the electrode holder. The electrode holder has a straight bar part(24), a hollow expansion part(25), and a male screw part(26). The electrode holder includes an inner container(30), and the inner container has a ring plate(31), a spot facing pat(33), an annular insulating material(34), a sleeve(35), a cone member(36), a flange(37), a nut(38), a ring washer(39a), and a belleville spring(39b).

Description

Polycrystalline Silicon Manufacturing Equipment {APPARATUS FOR PRODUCING POLYCRYSTALLINE SILICON}

The present invention relates to a polycrystalline silicon manufacturing apparatus for producing a rod of polycrystalline silicon by depositing polycrystalline silicon on a surface of a heated silicon mandrel.

This application claims priority with respect to Japanese Patent Application No. 2008-164298 for which it applied on June 24, 2008, and Japanese Patent Application No. 2009-135831 for which it applied on June 5, 2009, The content here Use it.

Conventionally, what is known by the Siemens method is known as a polycrystalline silicon manufacturing apparatus. In the polycrystal silicon manufacturing apparatus by the Siemens method, many silicon core rods are arrange | positioned in a reaction furnace. The silicon mandrel in the reactor is heated, and the raw material gas comprising a mixed gas of chlorosilane gas and hydrogen gas is supplied to the reactor and brought into contact with the heated silicon mandrel. Then, polycrystalline silicon produced by thermal decomposition and hydrogen reduction of the raw material gas is deposited on the surface of the silicon mandrel.

In such a polycrystalline silicon manufacturing apparatus, the silicon core rod is fixed in a state in which it is mounted on an electrode formed on the inner bottom of the reactor. Then, the electrode is energized by the silicon mandrel to generate the silicon mandrel by the resistance. At this time, the source gas ejected from below is brought into contact with the silicon core rod surface to form a rod of polycrystalline silicon. The electrodes holding the silicon mandrel are formed in plural so as to be distributed over almost the entire bottom surface of the reactor, and as described in Japanese Patent Laid-Open No. 2007-107030, an annular ring is formed in the through hole of the reactor bottom plate. It is formed in the state surrounded by the insulating material.

In the above-mentioned polycrystal silicon manufacturing apparatus, the gas temperature in a reaction furnace is high temperature at the highest 500-600 degreeC. Therefore, the electrode holder holding the electrode is allowed to cool by flowing coolant therein. However, since the insulating material formed between the bottom plate portion of the reactor and the electrode holder cannot be directly cooled, the shape is easily damaged due to heat in the reactor, and is likely to cause deterioration of the insulation function. In this case, in the case of using a ceramic-based insulating material, the thermal expansion difference between the bottom plate portion of the reactor and the electrode holder cannot be absorbed, which may lead to breakage.

This invention is made | formed in view of such a situation, Comprising: It aims at providing the polycrystal silicon manufacturing apparatus which can absorb the thermal expansion difference of the bottom plate part of an reactor and an electrode holder, and can maintain favorable insulation.

The polycrystalline silicon manufacturing apparatus of the present invention deposits polycrystalline silicon on the surface of the silicon mandrel by heating the silicon mandrel in a reaction furnace supplied with a source gas. The polycrystal silicon manufacturing apparatus of this invention has an electrode, an electrode holder, and an annular insulating material. An electrode extends and holds the silicon mandrel in the vertical direction. The electrode holder has a cooling flow path through which a cooling medium flows, and is inserted into the through hole formed in the bottom plate of the reactor to hold the electrode. The annular insulating material is disposed between the inner circumferential surface of the through hole and the outer circumferential surface of the electrode holder to electrically insulate between the bottom plate portion and the electrode holder. Further, in the polycrystalline silicon manufacturing apparatus of the present invention, an enlarged diameter portion in contact with at least a portion of an upper surface of the upper end portion of the annular insulating material is formed on an outer circumferential surface of the electrode holder, and a portion of the cooling passage is formed therein. It is.

As for the annular insulating material inserted in the bottom plate part of a reactor, the upper surface of the upper end part faces the inside of a reactor. Therefore, if the annular insulating material remains exposed inside the reactor between the inner circumferential surface of the through hole and the electrode holder, the radiant heat from the silicon core rod or the like in the reactor passes through the inner circumferential surface of the through hole and the electrode holder. It acts directly on the upper end of the insulation. In this invention, since the electrode holder bears radiant heat directed toward the upper surface by forming an enlarged diameter portion in contact with at least a portion of the upper surface of the upper end of the annular insulating material, the radiant heat acting directly on the annular insulating material can be reduced. In addition, since the cooling medium is also distributed in the enlarged diameter portion, the cooling effect of the annular insulating material can be enhanced.

Moreover, in the polycrystal silicon manufacturing apparatus of this invention, it is preferable that the said wide diameter part covers the said upper surface whole part of the said upper end part of the said cyclic insulating material.

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

Moreover, in the polycrystal silicon manufacturing apparatus of this invention, after cooling the said enlarged diameter part, it is preferable to cool the said electrode vicinity.

In this case, the cooling medium circulating in the electrode holder cools the enlarged diameter portion having a relatively low temperature, and then cools the vicinity of the relatively high temperature electrode, thereby keeping the expanded diameter at a low temperature, thereby more effectively preventing the annular insulating material from becoming a high temperature. can do.

Moreover, in the polycrystal silicon manufacturing apparatus of this invention, the said cooling flow path is an outer peripheral side flow path which distribute | circulates the said cooling medium toward the upper end part along the longitudinal direction in the said electrode holder, and the inside of the said outer peripheral side flow path. It is preferable to have an inner circumferential side flow path through which the cooling medium flows toward the lower end of the electrode holder along the longitudinal direction, and a part of the outer circumferential side flow path is formed in the enlarged diameter portion.

In this case, after the cooling medium flows through the outer circumferential portion in the electrode holder toward the upper end portion, and the inside thereof is distributed through the lower end portion, the electrode holder can be efficiently cooled down to the upper end portion.

Moreover, in the polycrystal silicon manufacturing apparatus of this invention, it is preferable that the said cyclic insulating material consists of resin which has elasticity. In this case, the breakage of the annular insulating material due to the thermal expansion difference between the bottom plate portion and the electrode holder is prevented, and the thermal expansion difference between the bottom plate portion and the electrode holder is absorbed by the annular insulating material, and the displacement of the silicon mandrel or the precipitated polycrystalline silicon Breakage is prevented.

According to the polycrystalline silicon manufacturing apparatus of the present invention, since the enlarged diameter portion formed in the electrode holder blocks the radiant heat from the silicon mandrel to the annular insulating material and cools the annular insulating material, the annular insulating material is effectively protected from the heat during the reaction. It is possible to maintain good insulation and elasticity of the annular insulating material. Therefore, a synthetic resin or the like can be used as the annular insulating material, and the soundness of the entire apparatus can be maintained, for example, the thermal expansion difference can be absorbed while securing the insulation between the bottom plate portion and the electrode.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the polycrystal silicon manufacturing apparatus of this invention is described based on drawing.

[First embodiment]

1 is an overall view of a polycrystalline silicon manufacturing apparatus to which the present invention is applied. The reactor 1 of the polycrystalline silicon manufacturing apparatus includes a bottom plate portion 2 constituting the furnace bottom and a steering-shaped bell 3 attached to the bottom plate portion 2 so as to be freely detachable; bell jar). The upper surface of the bottom plate part 2 is formed in a substantially flat horizontal plane. The bell jar 3 has a steering shape as a whole, and since the ceiling is domed, the inner space is formed with the highest central portion and the lowest peripheral portion. In addition, the wall of the bottom board part 2 and the bell jar 3 becomes a jacket structure (not shown), and is cooled by cooling water.

The bottom plate portion 2 has a plurality of electrode units 5 on which the silicon core rods 4 are mounted, and a jet nozzle (gas supply port) for blowing raw material gas containing chlorosilane gas and hydrogen gas into the furnace (6). ) And a plurality of gas outlets 7 for discharging the gas after the reaction out of the furnace are provided.

The blowing nozzles 6 of the source gas are dispersed in almost the entire area of the upper surface of the bottom plate portion 2 of the reactor 1 so that the source gas can be uniformly supplied to the silicon core rods 4, and a plurality of the nozzles are spaced at appropriate intervals. It is installed. These jet nozzles 6 are connected to the source gas supply source 8 outside the reaction furnace 1. In addition, a plurality of gas discharge ports 7 are provided at appropriate intervals in the circumferential direction near the outer circumferential portion on the bottom plate portion 2, and are connected to an external exhaust gas treatment system 9. The power supply circuit 10 is connected to the electrode unit 5. The bottom plate portion 2 has a jacket structure, and a cooling passage (not shown) is formed therein.

The silicon mandrel 4 is fixed in a state in which the lower end is inserted into the electrode unit 5, and is installed to extend upward, and connect one short length to the upper end so as to connect two of them in pairs. The member 12 is attached. This connecting member 12 is also formed of the same silicon as the silicon mandrel 4. By the two silicon core rods 4 and the connection member 12 which connects them, the seed assembly 13 is assembled so that it may become a (pi) shape (inverted U shape) as a whole. The seed granules 13 are arranged concentrically from the center of the reactor 1 because the electrode units 5 are arranged concentrically from the center of the reactor 1.

Specifically, as shown in FIG. 2, as the electrode unit 5 in the reactor 1, one electrode core 5A for silicon core rods holding one silicon core 4 and two silicon The double silicon electrode core electrode unit 5B which holds the mandrel 4 is arrange | positioned.

As shown in FIG. 2, these single silicon mandrel electrode units 5A and two silicon mandrel electrode units 5B are arranged in series using, for example, three sets of seed assemblies 13 as one unit. You can connect. At this time, one single silicon electrode mandrel electrode unit 5A, two two silicon mandrel electrode units 5B, and one single silicon mandrel electrode unit 5A are connected from the end of the unit row. Just list them in order. In this case, each seed assembly 13 is formed in three sets so as to span between four electrode units 5A and 5B. Both silicon mandrels 4 of one seed assembly 13 are held by adjacent different electrodes, respectively.

In short, one of the two silicon mandrels 4 of the seed assembly 13 is held in the single silicon mandrel electrode unit 5A, and two sets of seed assembly (in the two silicon mandrel electrode units 5B). The silicon core rods 4 of 13) are held one by one. Then, a power cable is connected to the single silicon core rod electrode unit 5A at both ends of the column so that a current flows. At this time, in the two silicon heart-shaped electrode units 5B, a current flows between the two electrodes 47 via the arm part 42 (refer FIG. 4).

In this manner, the two-core silicon mandrel electrode unit 5B holding two types of electrodes and holding one silicon mandrel 4 and two silicon mandrels 4 each holding two silicon mandrels 4. The number of electrode units can be reduced (for example, about 2/3) as compared with the case where all of them are held by forming the. When the number of electrode units is small in this manner, the through-holes formed in the bottom plate portion 2 of the reactor 1 can also be reduced, and the bottom plate portion 2 can be held in a steel structure. In addition, since a large number of silicon core rods 4 can be held with a small number of electrode units, many silicon core rods 4 can be provided in the reactor 1, and productivity can be improved. Moreover, since the number of electrode units is small, the cooling piping and power supply cable arrange | positioned under the bottom board part 2 can also be reduced, and the maintenance workability improves.

Next, the detail of each electrode unit structure is demonstrated.

First, the single silicon core electrode electrode unit 5A holding the single silicon core rod 4 will be described. As shown in FIG. 3, the electrode unit 5A is composed of an electrode holder 22 and an electrode 23. The electrode holder 22 is formed in an inserted state in the through hole 21 formed in the bottom plate portion 2 of the reactor 1, and the electrode 23 is formed at the upper end of the electrode holder 22 to form a silicon core rod ( 4) Maintain

As shown in FIG. 3, the electrode holder 22 is formed in rod shape by electrically conductive materials, such as stainless steel. The electrode holder 22 is formed by integrating a straight rod portion 24, a hollow disk-shaped enlarged diameter portion 25, and a male screw portion 26. The straight rod part 24 is inserted in the through-hole 21 along the up-down direction. The hollow disk-shaped enlarged diameter part 25 is formed coaxially with the electrode holder 22, is formed in the upper end part of the straight rod part 24, and is larger than the rod part 24 in diameter. Inside the enlarged diameter part 25, the circular space 25a is formed coaxially with the electrode holder 22, and the space 25a is larger in diameter than the rod part 24. As shown in FIG. The male screw portion 26 protrudes further upward from the upper surface of the enlarged diameter portion 25. Moreover, the male screw part 28 is formed in the position which protrudes from the bottom plate part 2 below the rod part 24. As shown in FIG.

The electrode holder 22 is formed hollow. The inner cylinder 30 which has an outer diameter smaller than the inner diameter of the electrode holder 22 in the inside of the electrode holder 22, and interrupts the inside of the electrode holder 22 by the space of the outer peripheral side and the space of the inner peripheral side (center part), It is provided coaxially with the electrode holder 22. The upper end of the inner cylinder 30 abuts on the inner surface of the upper end of the electrode holder 22, and an opening 30a communicating with the inside and the outside of the inner cylinder 30 is formed at this upper end. Thereby, the inner peripheral side flow path 27A and the inner cylinder 30 formed between the inner cylinder 30 and the electrode holder 22 from the rod part 24 to the male screw part 26 inside the electrode holder 22 by this. A cooling flow passage 27 is formed in which the inner circumferential side flow passage 27B formed therein communicates with the opening portion 30a. The cooling medium flows through this cooling flow path 27.

On the outer circumferential surface of the inner cylinder 30, a ring plate 31 is formed so as to be substantially orthogonal to the inner cylinder 30 at a position corresponding to the inner space 25a of the enlarged diameter portion 25. By this ring plate 31, the circulation direction of the cooling medium circulated in the outer circumferential side flow path 27A is guided to the space 25a in the enlarged diameter portion 25. On the outer circumferential surface of the inner cylinder 30, a plate-shaped spacer 32 which secures a gap between the inner circumferential surface of the electrode holder 22 and the outer circumferential surface of the inner cylinder 30 at a position corresponding to the male screw portion 28 is further provided. 30) extends along the axial direction.

On the other hand, the through hole 21 of the bottom plate portion 2 having the electrode holder 22 in the inserted state is a straight portion 21A and a tapered portion 21B in which the upper portion gradually expands upward. . 21 A of straight parts are formed in the inner diameter larger than the outer diameter of the rod part 24 of the electrode holder 22. As shown in FIG. As a result, a ring-shaped space is formed around the rod part 24. The tapered portion 21B is formed at an inclination angle of 5 ° to 15 ° with respect to the vertical axis, for example. In the upper end opening portion of the tapered portion 21B, a spot facing portion 33 having a diameter larger than the maximum inner diameter of the tapered portion 21B is formed.

An annular insulating material 34 is formed between the inner circumferential surface of the through hole 21 and the rod part 24 of the electrode holder 22 so as to surround the electrode holder 22. This cyclic insulating material 34 is formed of an insulating resin having a high melting point, such as a fluororesin represented by polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkane (PFA), for example. The annular insulating material 34 includes a sleeve 35 with a flange inserted into the straight portion 21A of the through hole 21 and a cone member 36 disposed in the tapered portion 21B of the through hole 21. It consists of two members). For example, PTFE used as the material for the annular insulating material 34 has a melting point (ASTM standard: D792) of 327 ° C, a bending modulus of elasticity (ASTM standard: D790) of 0.55 kPa, and a tensile modulus of elasticity (ASTM standard: D638) of 0.44 to 0.55. 선, the coefficient of linear expansion (ASTM standard: D696) is 10 × 10 ^-5 / ℃.

The cone member 36 is formed in the taper shape of the inclination-angle whose outer surface is the same as the inner peripheral surface of the taper part 21B of the through-hole 21. As shown in FIG. The cone member 36 is inserted into the through hole 21 from above the bottom plate portion 2 and abuts against the inner surface of the tapered portion 21B. The lower surface of the enlarged diameter part 25 of the electrode holder 22 is in contact with the upper surface of the upper end of the cone member 36. As for the enlarged diameter part 25, the outer diameter is set to be substantially equal to or slightly smaller with respect to the maximum outer diameter of the cone member 36, ie, the outer diameter of the upper end part upper surface, and the upper surface of the cone member 36 (ring-type insulation material 34) Covering the whole. If the distance between the enlarged diameter portion 25 and the spot facing portion 33 is sufficiently separated from each other so as not to be short-circuited, the outer diameter of the enlarged diameter portion 25 may be adjusted to increase the cooling effect. You can make it slightly larger. On the other hand, when the distance between the enlarged diameter portion 25 and the spot facing portion 33 is short, the outer diameter of the enlarged diameter portion 25 can be made slightly smaller than the outer diameter of the upper surface of the upper end of the cone member 36 in order not to cause a short circuit. .

The O-ring 43 is formed in the inner peripheral part of the outer peripheral surface and the upper end surface of the cone member 36, respectively. By these O rings 43, the airtightness between the cone member 36, the electrode holder 22, and the bottom plate part 2, ie, the airtightness in the through-hole 21 of the reaction furnace 1, is maintained.

The flanged sleeve 35 is inserted into the straight portion 21A so that the flange portion 37 integrally formed at the lower end portion thereof abuts against the rear surface of the bottom plate portion 2 of the reactor 1. The upper surface of the flange portion 37 is pressed to the rear surface of the bottom plate portion 2 by a nut 38 fitted to the male screw portion 28 of the electrode holder 22. Between the lower face of the flange portion 37 and the nut 38, the ring washer 39a, the disc spring 39b, and the ring washer 39a are arranged in this order. When pressing the upper surface of the flange portion 37 to the rear surface of the bottom plate portion 2 by the nut 38, the plate spring 39b is used to make an appropriate pressure. It is preferable that the ring washer 39a is made of stainless steel (SUS304), and it is preferable that the disc spring 39b is made of stainless steel (SUS631).

By tightening the nut 38 firmly, the gap between the enlarged diameter portion 25 and the nut 38 becomes small, so that the electrode holder 22 is pulled downward with respect to the bottom plate portion 2, so that the expanded diameter portion 25 and the nut The annular insulating material 34 is sandwiched between the 38. Moreover, the outer peripheral surface of the cone member 36 is pressed against the inner peripheral surface of the tapered portion 21B of the through hole 21 by the fitting force, so that the annular insulating material 34 and the electrode holder 22 are the bottom plate portion 2. It is fixed integrally to. At this time, while confirming the height position (protrusion height from the bottom plate portion 2 surface) of the lower surface of the enlarged diameter portion 25 of the electrode holder 22, the lower portion of the enlarged diameter portion 25 is brought close to the bottom plate portion 2. . At this time, the fitting amount of the nut 38 is adjusted so that an electric short circuit does not occur between the lower part of the enlarged diameter part 25 and the bottom plate part 2.

By elastic deformation of the disc spring 39b and the annular insulator 34 (the flanged sleeve 35 and the cone member 36 made of resin) between the electrode holder 22 and the bottom plate portion 2 Relative movement up and down is allowed. Thus, the thermal expansion difference between the electrode holder 22 and the bottom plate portion 2 is absorbed.

In this fixed state, the upper end of the cone member 36 of the annular insulating material 34 projects slightly upward from the upper end of the tapered portion 21B of the through hole 21 and faces in the spot facing portion 33. For this reason, the outer diameter of the cone member 36 is tapered part 21B so that the upper end part may protrude from the bottom face of the spot facing part 33, and the upper end part may not protrude upward from the upper end part of the spot facing part 33. It is set larger than the maximum outer diameter of.

On the other hand, the electrode 23 is formed in a cylindrical shape entirely by carbon or the like. The electrode 23 has a female screw portion 43 fitted to the male screw portion 26 of the electrode holder 22 at the lower end thereof, and has a hole 23a for fixing the silicon core rod 4 in the inserted state at the upper end thereof. , The hole 23a is formed along the shaft center.

1 The cooling channel 27 formed in the electrode unit 5A for silicon mandrel will be described. As shown in FIG. 3, the cooling medium flows into the outer circumferential side flow path 27A through the inlet 127A formed at the lower end of the electrode holder 22, and flows upward. The cooling medium is guided by the ring plate 31 and flows through the space 25a in the enlarged diameter portion 25, and then reaches the inside of the male screw portion 26, i.e., the vicinity of the electrode 23. As shown in FIG. The cooling medium flows into the inner cylinder 30 from the opening 30a formed in the upper end of the inner cylinder 30 when the inside of the outer circumferential side flow path 27A is filled up until it comes in contact with the inner surface of the upper end of the electrode holder 22. Thereafter, the cooling medium flows downward from the inside of the inner cylinder 30, that is, the inner circumferential side flow path 27B, and flows out from the outlet 127B formed at the lower end of the inner cylinder 30 to the outside of the electrode holder 22. . In other words, the cooling medium cools the relatively low temperature expansion part 25 during the flow of the outer circumferential side flow path 27A, and then cools the vicinity of the relatively high temperature electrode 23 and passes the electrode through the inner circumferential side flow path 27B. It is discharged from the holder 22.

Second Embodiment

2 This silicon core rod electrode unit 5B will be described. 2 This silicon heart-shaped electrode unit 5B is enlarged and shown in FIG. 2 The electrode unit 5B for silicon mandrel is inserted into an electrode holder 46 formed in an inserted state in a through hole 21 formed in the bottom plate portion 2 of the reactor 1 and an upper end of the electrode holder 46. The point of having the structure provided with the formed electrode 47 is the same structure as 5 A of electrode cores for silicon core rods. In the double silicon electrode rod 5B, the electrode holder 46 is bifurcated at the upper end, and the electrodes 47 are formed at both ends thereof. It differs from the rod electrode unit 5A.

The electrode holder 46 of the electrode unit 5B has a structure in which a rod portion 41 forming a rod shape and an arm portion 42 orthogonal to an upper end of the rod portion 41 are integrally formed. The electrode holder 46 is formed of a conductive material such as stainless steel. The hollow annular enlarged diameter part 45 is formed in the middle position of the rod part 41 in the longitudinal direction. Moreover, the male screw part 46a similar to the male screw part 28 in 1st Embodiment is formed in the position which protruded from the lower surface of the bottom board part 2 of the rod part 41. As shown in FIG.

Spot facing formed in the through hole 21 (straight portion 21A, tapered portion 21B) of the bottom plate portion 2 having the electrode holder 46 inserted therein, and the upper opening of the tapered portion 21B. Part 33, annular insulating material 34 (sleeve 35 with flange, cone member 36) formed between the inner circumferential surface of the through hole 21 and the rod part 41 of the electrode holder 46, The nut member 38, ring washer 39a, and the like, which are screwed to the male screw portion 46a of the rod portion 41, have the same configuration and effect as those of the one-core silicon mandrel electrode unit 5A. Omit.

The arm part 42 of the electrode holder 46 extends horizontally from the upper end of the rod part 41 to the left-right direction, respectively, and forms the T shape with the rod part 41. FIG. The arm part 42 is provided with the female screw hole 42a which penetrates the left and right both ends in the vertical direction, respectively and screwes the electrode 47 together. The electrode 47 is screwed into this female screw hole 42a and is exposed to the upper portion of the arm portion 42. The nut member 44 is attached to the base end of the electrode 47 on the arm part 42. The nut member 44 is formed in the column shape, and the internal thread part which is screwed to the electrode 47 is formed in the inner peripheral part. The nut member 44 is preferably formed of carbon or the like.

The arm portion 42 surrounds the straight inner space 42b extending in the left-right direction and the outer circumference of each female threaded hole 42a in a C-shape, and is in communication with the straight inner space 42b, respectively. The shape inner space 42c is formed. The straight inner space 42b is partitioned up and down by the third partition plate 48C.

The upper space of the rod part 41 of the electrode holder 46 is divided into the left space 41c and the right space 41d by the second partition plate 48B connected to the third partition plate 48C. have. At the lower end of the second partition plate 48B, a first disk-shaped partition plate 48A is formed which is substantially orthogonal to the axial direction of the rod portion 41 and partitions the inside of the rod portion 41 up and down. In the first partition plate 48A, a through hole 148A opened only on the right side of the second partition plate 48B is formed. Furthermore, the rod part 41 is provided in the rod part 41 with respect to the 1st opening part 41a formed below the 1st partition plate 48A, and the upper part of the 1st partition plate 48A, and the 1st opening part 41a. The second opening part 41b formed in the 180 degree opposite side through the axis line of () is formed.

The enlarged diameter part 45 is an annular member which forms the annular space 45b in the outer peripheral surface of the rod part 41 by fitting to the outer peripheral surface of the rod part 41. The annular space 45b in the enlarged diameter portion 45 has a first opening portion 41a opened downward of the first partition plate 48A and a second opening portion opened upward of the first partition plate 48A ( It communicates with the rod part 41 via 41b). Moreover, the rounded wall part 45a is formed in the outer peripheral part of the upper surface of the enlarged diameter part 45. As shown in FIG.

Moreover, the inner cylinder 49 which communicates with 41 d of right side spaces through the through-hole 148A is attached to the lower surface of 48 A of 1st partition plates substantially coaxially with the rod part 41. As shown in FIG. The inner cylinder 49 has a space on the outer circumferential side (the outer circumferential side flow path 40A) and an inner circumferential side (the inner circumferential side flow path 40B) below the first partition plate 48A. ) Is blocked.

In this way, since the two silicon core rod electrode units 5B are configured, the outer circumferential side flow passage 40A, the inner circumferential side flow passage 40B and the enlarged diameter portion 45 in the lower portion of the rod part 41 are formed in the electrode holder 46. By the annular space 45b, the left space 41c and the right space 41d above the rod portion 41, the straight inner space 42b of the arm portion 42 and the arc-shaped inner space 42c. The cooling flow path 40 is formed.

In the cooling flow path 40, a cooling medium flows in from the lower end part of the electrode holder 46 to the outer peripheral side flow path 40A formed between the outer peripheral surface of the inner cylinder 49, and the inner peripheral surface of the rod part 41, and flows upwards. do. When the first partition plate 48A is reached, the cooling medium is blocked by the first partition plate 48A and flows into the annular space 45b in the enlarged diameter portion 45 through the first opening 41a, The enlarged diameter part 45 is cooled. Thereafter, the cooling medium flows through the second opening portion 41b to the upper side of the first partition plate 48A and to the left side of the second partition plate 48B, that is, to the left space 41c.

The cooling medium which flowed into the left space 41c is an arc shape of the left side from the lower left of the straight inner space 42b of the arm part 42 by the 2nd partition board 48B and the 3rd partition board 48C. It is led to the interior space 42c. Thereafter, the cooling medium flows through the upper side of the third partition plate 48C in the straight inner space 42b, and the lower right side of the straight inner space 42b through the right arc-shaped inner space 42c. Is induced. In the meantime, the cooling medium cools the vicinity of the electrode 47. And when a cooling medium flows through 41 d of right spaces along the 2nd partition board 48B, and reaches the 1st partition board 48A, the inner peripheral side flow path in the inner cylinder 49 through the through-hole 148A. 40B), and is discharged from the electrode holder 46.

In the polycrystalline silicon manufacturing apparatus configured as described above, when the electrode core 5 (electrode unit 5A, electrode unit 5B) is energized by the silicon core 4, the silicon core 4 is placed in a resistance heating state. In addition, even between each silicon core rod 4, it receives mutual radiant heat from the adjacent silicon core rod 4, mutually heats them, and raises them, and it becomes a high temperature state. The source gas in contact with the surface of the silicon core rod 4 in this high temperature state reacts to precipitate polycrystalline silicon.

Radiant heat from this silicon mandrel 4 also acts on each electrode unit 5A and electrode unit 5B on the bottom plate portion 2 of the reactor 1, and the annular insulating material 34, which is weak to heat, also has an upper end portion. Since a part is exposed in the spot facing part 33, it is thought that it will be influenced by heat. However, as shown in FIGS. 3 and 4, the upper surface of the upper end portion of the annular insulating material 34 covers the enlarged diameter portion 25 of the electrode holder 22 and the enlarged diameter portion 45 of the electrode holder 46, respectively. Since it is arrange | positioned so that, the radiant heat which acts directly on this upper surface will become small. In addition, since the electrode holder 22 and the electrode holder 46 are cooled by a cooling medium circulating therein, the annular insulating material 34 is also effectively cooled. In particular, the annular insulating material 34 is effectively cooled by circulating a cooling medium in a space formed inside the enlarged diameter portion 25 and the enlarged diameter portion 45 covering the upper surface of the upper end portion.

Thus, even in the high temperature reaction furnace 1, since the deformation | transformation, deterioration, etc. by high temperature are suppressed and the elasticity is maintained, the cyclic | annular insulation material 34 can absorb the thermal deformation of each member, and the effect | action of a stress is suppressed. It can be suppressed, and the function of a facility can be maintained suitably.

In addition, this invention is not limited to the structure of the said embodiment, In a detailed structure, various changes can be added in the range which does not deviate from the meaning of this invention.

For example, the enlarged diameter portion of the electrode holder may not necessarily cover the entire upper surface of the upper surface of the annular insulating material, and may cover at least a portion of the upper surface such that deformation or deterioration of the annular insulating material can be prevented. It may be formed.

In addition, in the said embodiment, although only one system | path is provided, you may provide the cooling flow path for cooling the enlarged diameter part and the cooling flow path for cooling the electrode vicinity separately.

As mentioned above, although preferable Example of this invention was described, this invention is not limited to these Examples. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the invention. The invention is not limited by the foregoing description, but only by the scope of the appended claims.

1 is a perspective view partially cut out the bell jar of the reactor.

FIG. 2 is a cross-sectional view of the reactor shown in FIG. 1. FIG.

FIG. 3 is an enlarged cross sectional view showing an electrode unit for silicon core rods in the reactor shown in FIG. 2; FIG.

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

※ Explanation of codes for main parts of drawing

1: reactor

2: bottom plate

4: silicone mandrel

5, 5A, 5B: electrode unit

21: through hole

22, 46: electrode holder

23, 47: electrode

25, 45: enlarged neck

27, 40: cooling flow path

27A, 40A: Outer side flow path

27B, 40B: Inner circumference side flow path

34: annular insulation

Claims (5)

A polycrystalline silicon manufacturing apparatus for depositing polycrystalline silicon on the surface of a silicon mandrel by heating a silicon mandrel in a reaction furnace supplied with a source gas, An electrode for extending and maintaining the silicon mandrel in a vertical direction; An electrode holder having a cooling flow path through which a cooling medium is circulated, inserted into a through hole formed in the bottom plate of the reactor, and holding the electrode; A ring-shaped insulating material disposed between the inner circumferential surface of the through hole and the outer circumferential surface of the electrode holder to electrically insulate between the bottom plate portion and the electrode holder, And an enlarged diameter portion formed in contact with at least a portion of an upper surface of the upper end portion of the annular insulating material on the outer circumferential surface of the electrode holder, and having a portion of the cooling passage formed therein. The method of claim 1, The enlarged diameter portion covers the entire upper surface of the upper end portion of the annular insulating material. The method of claim 1, The cooling medium cools the vicinity of the electrode after cooling the enlarged diameter part. The method of claim 1, The cooling passage includes an outer circumferential side passage through which the cooling medium flows toward the upper end portion along the longitudinal direction thereof, and an inner side of the outer circumferential side passage toward the lower end portion of the electrode holder along the longitudinal direction. A polycrystalline silicon manufacturing apparatus, comprising: an inner circumferential side flow path through which the cooling medium flows, and a part of the outer circumferential side flow path is formed in the enlarged diameter portion. The method of claim 1, The cyclic insulating material is made of a resin having elasticity polycrystalline silicon production apparatus, characterized in that.

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