JP2007314394A - Device and method for feeding raw material by czochralski method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for feeding a raw material, which has a raw material feeding tube having a simple structure and can avoid adverse effects or the like on the growth of a silicon single crystal by suppressing damages in a crucible or splashing of raw material melt by reducing the raw material feeding speed; and to provide a method for feeding the raw material by using the same. <P>SOLUTION: The device for feeding the raw material performs additional charge or recharge of a granular and lumpy solid raw material to the raw material melt 5 in a crucible 1 and has a portable raw material feeding hopper 6, a raw material feeding tube 7, and a mechanism of charging the raw material to be charged after once stopping the raw material at the tip end of the raw material feeding tube 7. The mechanism is constituted in such a way that the raw material to be charged is once stopped at the contact part where the surface of a stopping matter (a columnar silicon 8 is preferable) constituted ascendably/descendably is brought into contact with the tip opening part of the raw material feeding tube 7 and thereafter, the raw material is charged into the crucible 1 from the tip opening part of the raw material feeding tube 7 by gradually raising the stopping matter. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a raw material supply apparatus used for forming a raw material melt and a raw material supply method employed in the apparatus in single crystal growth by the Czochralski method (hereinafter referred to as “CZ method”). More specifically, the present invention relates to a raw material supply apparatus used for additional charge or recharge for charging a solid raw material into a raw material melt in a crucible when growing a silicon single crystal, and a raw material supply method using the apparatus.

  Usually, in the growth of a silicon single crystal by the CZ method, solid polycrystalline silicon charged as an initial charge in a crucible is heated and melted by a heater surrounding the crucible. When the raw material melt is formed in the crucible, the seed crystal held on the crucible is lowered while rotating the crucible in a certain direction, and immersed in the raw material melt in the crucible. Thereafter, by raising the seed crystal while rotating the seed crystal in a predetermined direction, the cylindrical silicon single crystal is pulled up and grown below the seed crystal.

  The solid raw material charged into the crucible as the initial charge is polycrystalline silicon of various shapes such as rod, lump, or granule, and each is supplied alone or in combination, and is used to grow a silicon single crystal. It becomes the raw material of the liquid.

  In the growth of a silicon single crystal by such a CZ method, since the polycrystalline silicon raw material to be used has a wide variety of shapes, the amount of solid raw material that can be charged in the crucible is limited, and the first to the crucible is limited. In charging, the target amount (final charge amount) cannot be charged.

  In order to avoid a decrease in productivity due to the above-mentioned causes, it is necessary to supplement the shortage of the raw material melt to ensure a desired amount of the melt, and after the initial charge to the crucible, additional solid raw material is supplied. “Additional charge” is performed as a technology.

  In other words, “additional charge” is a technology that increases the amount of the raw material melt in the crucible by melting the solid raw material initially charged in the crucible and then adding additional solid raw material to the formed raw material melt. It is. By applying this “additional charge”, the volume of the crucible to be used can be used effectively, and the productivity in silicon single crystal growth can be improved.

  Furthermore, in the growth of a silicon single crystal by the CZ method, a technique of supplying a solid material called “recharge” is also performed. More specifically, after the first single crystal is grown and pulled, a solid raw material in an amount commensurate with the decrease due to the pulling of the raw material melt is added to the residual melt in the crucible.

  In other words, by “recharging”, a predetermined amount of the raw material melt is re-formed in the crucible, and the pulling of the single crystal is repeated to increase the number of crystals pulled per crucible.

  Therefore, by adopting “recharge”, the cost can be reduced by using the crucible efficiently, and productivity can be improved and the growth cost of the silicon single crystal can be reduced as in the “additional charge” described above.

  However, the raw material supply by “additional charge” or “recharge” is based on a method of additionally charging agglomerated solid raw material into the raw material melt in the crucible using a raw material supply device inserted in the pulling furnace. For this reason, as additional raw materials are added, the crucible is damaged, or splashes of the raw material melt adhere to the components in the chamber due to the splash of the raw material melt. There was a problem that had a negative effect on the development of the children.

  For this reason, various proposals have conventionally been made regarding “additional charge” and “recharge”. For example, in Patent Document 1, in order to perform additional charging, a supply device provided with a movable hopper for storing silicon raw material can be attached to and detached from the container (CZ furnace) side opening. Position of the tip of the supply pipe and the melt surface of the crucible by moving the raw material supply pipe provided with an opening and movably provided inside and outside the supply device side opening (inside and outside the furnace) A method of adjusting the relationship and supplying raw materials into the quartz crucible has been proposed. Furthermore, a method is described in which the shape of the supply pipe is bent in order to reduce the supply speed of the raw material.

Japanese Patent Laid-Open No. 2003-2777

  As described above, in the raw material supply by “additional charge” or “recharge”, agglomerated solid raw material is additionally added to the raw material melt in the crucible, so that the crucible is damaged or the raw material melt is splashed. There are problems such as adverse effects on single crystal growth.

  As a method for preventing this, the above-mentioned Patent Document 1 proposes a method in which the shape of the supply pipe is bent to reduce the supply speed of the raw material, and the falling speed of the raw material is ensured without causing clogging or the like in the supply pipe. Can be adjusted. However, the structure of the supply pipe has to be complicated, and it is necessary to increase the installation space in the furnace, so that the pulling of the silicon single crystal itself tends to be hindered.

  The present invention has been made in view of such a situation, and is a silicon single crystal pulling apparatus (a silicon single crystal growing (manufacturing) apparatus by CZ method) using agglomerated solid raw material. The material supply by the CZ method, which can simplify the structure of the material supply pipe and reduce the material supply speed when additional charging or recharging is performed on the material melt in the crucible placed in the “pulling furnace”) An object is to provide an apparatus and a raw material supply method using the apparatus.

  As a result of repeated studies to solve the above problems, the present inventor temporarily stops the raw material discharged from the raw material supply pipe installed in the pulling furnace to supply the agglomerated solid raw material at the tip of the supply pipe Then, it was found that if the raw material is dropped thereafter, the raw material supply speed can be surely reduced and the structure of the raw material supply pipe can be simplified.

  For example, if there is a “stop” to prevent the discharge of the raw material at the tip opening of the raw material supply pipe, and after stopping the discharge of the raw material there, if the stop is removed, the raw material will naturally move from that position. Since it falls, the raw material supply speed falls reliably. In addition, this operation can be easily performed by suspending a stationary object having a relatively large mass in a state where it can be raised and lowered at the tip opening of the raw material supply pipe.

  The present invention is an invention made based on such a concept and knowledge, and the gist thereof is a raw material supply apparatus used in the CZ method of (1) below and a raw material supply method of (2) below using the apparatus. .

  (1) A raw material supply device that is used for growing a single crystal by the Czochralski method and additionally charges or recharges a solid material in the form of agglomerates to a raw material melt in a crucible, and a solid raw material to be charged into the crucible A portable raw material supply hopper for storage, a raw material supply pipe for charging solid raw material in the raw material supply hopper into the crucible, and a mechanism for charging the charged raw material once stopped at the tip of the raw material supply pipe A raw material supply apparatus comprising:

  In the raw material supply apparatus of (1), after stopping the raw material to be input at the front end of the raw material supply pipe, a mechanism for introducing the stop is arranged in the vicinity of the front end of the raw material supply pipe and configured to be movable up and down. The raw material charged at the contact portion between the surface and the front end opening of the raw material supply pipe is temporarily stopped, and then the stop object is gradually raised so that the front end opening of the raw material supply pipe and the surface of the stop object are If the material is configured such that the contact is released and the material is charged into the crucible, the material supply speed can be reduced with a very simple structure.

  In this raw material supply apparatus, it is preferable that the stopping object is cylindrical silicon and the surface of the stopping object is a cylindrical surface of cylindrical silicon, so that contamination of the raw material melt in the crucible can be avoided.

  In addition, the “contact is released” means that the opening is opened by separating the tip opening and the surface of the stationary object from the state where the opening is blocked by the contact between the tip opening and the surface of the stationary object. It means becoming a state.

  (2) A raw material supply method for additionally charging or recharging a solid material in the form of agglomerates to a raw material melt in a crucible when a single crystal is grown by the Czochralski method, comprising a raw material supply pipe from a portable raw material supply hopper The solid raw material discharged to the raw material supply pipe is temporarily stopped at the contact portion between the front end opening of the raw material supply pipe and the surface of the stopped object, is deposited on the raw material supply pipe, and then the stopped object is gradually raised to form the raw material supply pipe The raw material supply method which cancels | releases the contact of the front-end | tip opening part and the surface of the said stop thing, and throws a solid raw material in a crucible.

  In this raw material supply method, it is desirable that the stopping object is cylindrical silicon and the surface of the stopping object is a cylindrical surface of cylindrical silicon, so that contamination of the raw material melt in the crucible can be avoided.

  The “granular solid raw material” defined in the present invention is not limited to simply agglomerated (granular or agglomerated) polycrystalline silicon, but also includes rod-shaped and other forms of polycrystalline silicon. As the raw material, it is desirable to use an agglomerated solid raw material that has low raw material costs and does not cause cracks due to rapid heating. In this case, it is more desirable to use an agglomerated polycrystalline silicon raw material having a particle size of 10 mm to 25 mm which can be easily obtained.

  According to the raw material supply apparatus and the raw material supply method according to the CZ method of the present invention, when additional charging or recharging is performed on the raw material melt in the crucible, the raw material supply apparatus including the raw material supply pipe having a very simple structure is used. Supply speed can be slowed down.

  As a result, damage to the crucible that occurs as the raw material is charged, shortening of component life due to adhesion of raw material melt droplets to chamber components, adverse effects on single crystal growth, etc. are avoided. It can contribute to the improvement of productivity.

  Hereinafter, the raw material supply apparatus and the raw material supply method of the present invention will be described in detail.

  The raw material supply apparatus according to the present invention described in the above (1) is a raw material supply apparatus that is used for growing a single crystal by the Czochralski method, and additionally charges or recharges agglomerated solid raw material to a raw material melt in a crucible. A portable raw material supply hopper for storing a solid raw material to be charged into the crucible; a raw material supply pipe for charging the solid raw material in the raw material supply hopper into the crucible; and A device that includes a mechanism that temporarily stops at the tip and then throws it in.

  That is, the greatest feature of the raw material supply apparatus of the present invention is that a mechanism is provided in which the raw material to be input is temporarily stopped at the tip of the raw material supply pipe and then input. This is to reduce the supply speed of the raw material to be charged (that is, the speed at which the raw material is charged into the raw material melt in the crucible). It is not limited to.

  An example suitable as a mechanism for charging the raw material once stopped at the tip of the supply pipe will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing the entire configuration of a single crystal pulling furnace according to the CZ method in which the raw material supply apparatus of the present invention is arranged.

  As shown in FIG. 1, the pulling furnace is composed of a furnace body portion (main chamber) in which the crucible 1 is disposed and a portion (pull chamber) for growing and pulling a single crystal above the furnace body portion. The crucible 1 is arranged in the case. The crucible 1 has a double structure in which an inner quartz crucible 1a and an outer graphite crucible 1b are combined, and is supported on a support shaft 2 via a crucible receiver (not shown). The support shaft 2 drives the crucible 1 to move up and down in the axial direction or to rotate in the circumferential direction.

  The heater 3 is arranged so as to surround the crucible 1. On the further outer side of the heater 3, a heat insulating material 4 is disposed along the inner surface of the furnace body portion. The solid raw material charged as an initial charge into the crucible 1 is melted by the heating of the heater 3 to form a raw material melt 5. After the initially charged solid raw material is melted, additional charging is performed in order to supplement the shortage of the raw material melt 5 in the crucible 1 and secure a desired amount of melt.

  The raw material supply apparatus of the present invention is an apparatus used for this purpose, and after the raw material supply hopper 6, the raw material supply pipe 7, and the raw material to be charged are temporarily stopped at the tip of the raw material supply pipe. And a mechanism for charging.

  The raw material supply hopper 6 is for storing the solid raw material to be charged into the crucible 1, and the raw material is accurately input to each of the pulling furnaces so that it can immediately respond to additional charging in a plurality of pulling furnaces. It is made portable so that it can. When the raw material supply hopper 6 is portable, it can be transported by a crane or a dedicated transport mechanism can be provided.

  However, in this case, the internal structure of the pulling furnace may be complicated. For example, the lifting device used in the magnetic field application device not shown in FIG. 1 is used as the transport mechanism for the raw material supply hopper 6. Thus, the internal structure of the pulling furnace can be simplified. On the outlet side of the raw material supply hopper 6, an on-off valve 6a for adjusting the amount of the solid raw material charged is attached.

  The bottom surface of the raw material supply hopper 6 is inclined as shown in the figure. The inclination angle is desirably 45 ° or more in order to smoothly discharge the stored raw materials. The solid raw material (polycrystalline silicon) has various shapes and sizes, and the raw material can be discharged even if the inclination angle is less than 45 ° if it is a small granular material having a particle size of about several millimeters, but it is easily available. When a polycrystalline silicon raw material having a particle size of 10 mm to 25 mm is used, the raw material may be clogged in the hopper 6 unless the inclination angle is 45 ° or more, and the raw material may not be discharged smoothly.

  The raw material supply pipe 7 is for charging the solid raw material in the raw material supply hopper 6 into the crucible 1. Therefore, it is arranged obliquely downward from the outside to the inside of the pulling furnace. The tip opening is processed to have a cross-sectional shape as shown in FIG. As will be described below, this is because the tip opening is closed by contacting with the cylindrical surface of the cylindrical silicon 8 and the charged raw material is temporarily stopped there.

  The raw material supply pipe 7 is in the vicinity of the attachment portion to the pulling furnace, and is connected to the discharge side of the hopper 6 automatically or manually, and the lower part (slope pipe 7b) fixed to each pulling furnace. It is desirable to have a structure divided into (1) and (2). The oblique tube 7a is configured to be movable so that it can be easily connected to the oblique tube 7b when the raw material is charged. Thus, for example, after the raw material supply hopper 6 is conveyed to a pulling furnace to be additionally charged, the inclined tube 7a is moved in the direction of the inclined tube 7b fixed to the pulling furnace (that is, the tip of the inclined tube 7a is inclined tube). The slant tube 7a and the slant tube 7b are connected by moving so as to enter the inside of the b).

  The reason for this is that if the entire raw material supply hopper 6 and the raw material supply pipe 7 are made portable, the raw material supply apparatus itself becomes a large-scale apparatus, so that the raw material supply pipe 7 is divided as described above. However, by minimizing the portion fixed to the pulling furnace, the equipment on the pulling furnace side can be simplified as much as possible, and the raw material supply apparatus can be simplified as a whole.

  The insides of the raw material supply pipe 7 and the hopper 6 are preferably made of quartz. This is because the raw material supply pipe 7 is used under special conditions such as high temperature, reduced pressure, and inert gas atmosphere in the pulling furnace, and it is necessary not to adversely affect the quality of the silicon single crystal. However, since the tip of the quartz raw material supply pipe is easily cracked by contact with other substances, it is desirable to have a structure that prevents cracking of the tip, such as attaching a silicon ring to the tip.

  3A and 3B are views showing a silicon ring attached to the tip of the raw material supply pipe and its attached state, wherein FIG. 3A is a sectional view after attachment, FIG. 3B is a perspective view of the silicon ring, and FIG. FIG. FIG. 4 is a view schematically showing a longitudinal section in the vicinity of the tip of the raw material supply pipe used at this time.

  As shown in FIG. 3A, the silicon ring 12 is attached to the raw material supply pipe in a state of projecting about 10 mm from the tip of the raw material supply pipe (slanting tube 7b). This is a silicon ring inserted into the oblique tube B from the side opposite to the distal end portion of the oblique tube b (the side connected to the oblique tube A) and attached to the distal end portion. Thus, the tip of the inclined tube 7b is slightly narrowed.

  The mechanism illustrated in FIG. 1 is adopted as a mechanism for stopping the raw material to be input once stopped at the tip of the raw material supply pipe. That is, when the cylindrical silicon 8 is used as a stop, the cylindrical silicon 8 configured to be movable up and down is disposed in the vicinity of the tip of the raw material supply pipe 7, and the cylindrical surface of the cylindrical silicon 8 and the raw material supply pipe 7 are arranged. The raw material thrown in at the contact portion with the front end opening portion is temporarily stopped, and then the cylindrical silicon 8 is gradually raised, whereby the front end opening portion of the raw material supply pipe 7 and the cylindrical surface of the cylindrical silicon 8 are A mechanism is adopted in which the contact is released and the raw material is put into the crucible 1.

  The cylindrical silicon 8 is positioned above the crucible 1 in which the raw material melt 5 is formed via a hanging jig 10 connected to the lower end of a pulling shaft 9 suspended from above the furnace body. The cylindrical surface and the tip opening of the raw material supply pipe 7 are suspended at a position where they can be brought into contact with each other. Instead of the suspension, for example, a method of fixing to a holding jig configured to be movable up and down may be employed. The pull-up shaft 9 is driven up and down by a drive mechanism (not shown) provided at the uppermost part of the pulling furnace, so that the cylindrical silicon 8 also moves up and down.

  The reason why silicon is used as a stopper for the charged raw material is to avoid contamination of the raw material melt by using a material other than silicon.

  In addition, the cylindrical shape of the stationary object (silicon) has a circular horizontal cross section, so there is no need to consider the direction of the stationary object in the horizontal direction, and the function as a stationary object can be demonstrated simply by determining the position. Because you get.

  There is no particular limitation on the size (diameter, height, etc.) of the cylindrical silicon 8. As long as it has a diameter, a height and the like that can function to temporarily stop the raw material charged at the contact portion between the cylindrical surface of the cylindrical silicon 8 and the tip opening of the raw material supply pipe 7 as described above. Good. When the cylindrical silicon 8 is suspended through the suspension jig 10, the cylindrical silicon 8 is formed so that a gap is generated in the contact portion due to the pressure of the charged raw material and the function is not impaired. It is also necessary to have a certain mass.

  As shown in FIG. 1, the bottom surface of the cylindrical silicon 8 is preferably an inverted cone. By adopting such a shape, it is possible to drop the solid raw material falling from the tip of the raw material supply pipe 7 so as to be half along the inverted conical surface and put it in the vicinity of the center of the crucible.

  The raw material supply method of the present invention described in (2) is a method using the apparatus of the present invention described in (1). Hereinafter, the raw material supply method of the present invention will be described by taking as an example a case where an additional charge is performed after the initial charge using a raw material supply apparatus using cylindrical silicon as a stop.

  2A and 2B are diagrams for explaining the raw material supply method of the present invention, in which FIG. 2A is a state before the raw material is charged into the raw material supply pipe, and FIG. 2B is a state where the charged raw material is once stopped at the contact portion. , (C) shows the state where the contact is released and the raw material is put into the crucible.

  First, the raw material supply pipe 7 (slant pipe 7b) is attached and fixed or installed in the pulling furnace in which the crucible for which the initial charge has been completed is disposed. Thereafter, the raw material supply hopper to which the raw material supply pipe is connected is transported to the pulling furnace, installed at a predetermined location, and the tip of the inclined tube 7a (not shown) is moved so as to enter the inside of the inclined tube 7b. 7a and the inclined tube 7b are connected. And the inside of a pulling furnace and a raw material supply apparatus is pressure-reduced, and it substitutes with an inert gas.

  Next, the cylindrical silicon 8 prepared in advance is lowered from above the pulling furnace and is arranged near the tip of the raw material supply pipe 7 so that the cylindrical surface of the cylindrical silicon 8 and the tip opening of the raw material supply pipe 7 are disposed. And contact. FIG. 2A shows a state where the cylindrical surface of the cylindrical silicon 8 and the tip opening of the raw material supply pipe 7 are in contact with each other.

  Subsequently, the solid raw material is supplied into the raw material supply pipe 7 from the raw material supply hopper. Since the front end opening of the raw material supply pipe 7 is blocked by the cylindrical surface of the cylindrical silicon 8 in contact therewith, as shown in FIG. 2B, the charged raw material 11 is temporarily stopped there. In the initial stage of raw material charging, a granular raw material having a small particle size falls into the raw material melt 5 through the gap between the contact portions, but the raw material is deposited on the contact portion in a short time.

  Next, as shown by an arrow in FIG. 2C, the contact between the tip opening of the raw material supply pipe 7 and the cylindrical surface of the cylindrical silicon 8 is released by gradually raising the cylindrical silicon 8. Thus, the closed end opening is opened, and the raw material 11 is charged into the raw material melt 5 in the crucible 1.

  The distance between the tip of the raw material supply pipe 7 and the liquid surface of the raw material melt 5 at the time of charging is preferably 200 mm or more and 300 mm or less. This is because such a distance is optimal in order to prevent the raw material melt from splashing by the charged solid raw material and to make it easy for the raw material to fall near the center of the crucible.

  As described above, the case where the raw material melt in the crucible is additionally charged has been described as an example. However, the raw material supply apparatus and the raw material supply method of the present invention can be similarly applied to the case of recharging.

  According to the raw material supply apparatus and the raw material supply method of the present invention, since the raw material supply speed can be reduced, the crucible damage caused by the raw material input and the components in the chamber of the raw material melt are splashed. Adhesion to the substrate can be suppressed, and adverse effects on the growth of the silicon single crystal can be avoided. In addition, since a raw material supply apparatus including a raw material supply pipe having an extremely simple structure is used, the pulling of the silicon single crystal itself is not hindered.

  In order to confirm the effect of the raw material supply apparatus and raw material supply method of the present invention, 100 kg of high-purity polycrystalline silicon was initially charged in a quartz crucible having an inner diameter of 22 inches arranged in the pulling furnace having the structure shown in FIG. After melting, 40 kg of the raw material melt in the crucible was additionally charged using the raw material supply apparatus of the present invention. At that time, a predetermined amount of boron was added as a dopant to the raw material melt. The amount of boron added was adjusted so that the specific resistance was 10 Ωcm in the first half of the silicon single crystal when the silicon single crystal was grown.

  In the additional charge, the inside of the pulling furnace (inside the chamber) was an argon atmosphere.

  After additional charging, a p-type <100> silicon single crystal having a diameter of 200 mm was grown. For comparison, a p-type <100> silicon single crystal having a diameter of 200 mm is also obtained after additional charging in the same manner as described above using a conventional raw material supply apparatus that does not use a stopping object that temporarily stops the charged raw material. I grew up.

  After the growth of the silicon single crystal, the raw material input state at the time of additional charge to the raw material melt in the crucible was evaluated. The evaluation item was “the state of the inner surface of the quartz crucible” after pulling the single crystal, and the pull rate of the single crystal to be grown was increased as much as possible to reduce the remaining melt as much as possible.

  Further, three batches of single crystals were grown, and the yield rate of silicon single crystals was evaluated. The “non-defective rate of silicon single crystal” is the ratio of the number of passes (all ends with a single crystal) to the total number of pulled single crystals.

  Table 1 shows the evaluation results. In Table 1, “non-defective product rate of silicon single crystal” is indicated by 1 as a non-defective product rate of silicon single crystal when additional charging is performed using a conventional raw material supply apparatus.

  As shown in Table 1, the non-defective rate of the silicon single crystal is higher when the additional charge is made using the raw material supply apparatus of the present invention that uses a stop (cylindrical silicon) that temporarily stops the charged raw material. Compared to the case of using a conventional raw material supply apparatus, the result was 15% higher, and good results were obtained.

  With respect to the state of the inner surface of the quartz crucible, when the raw material supply apparatus of the present invention was used, no dent scratches on the inner surface of the crucible and no splash of the raw material melt were observed.

  On the other hand, when the conventional raw material supply apparatus was used, many dent scratches considered to be due to the additional charge were observed. This is presumed to be due to the high charging speed of the solid raw material in the additional charge. It is considered that the non-defective product rate of the silicon single crystal deteriorated due to quartz pieces or bubbles from the dent scratch. Moreover, the splash of the raw material melt was observed above the level of the raw material melt due to the initial charge.

  According to the raw material supply apparatus and the raw material supply method according to the CZ method of the present invention, when additional charging or recharging is performed on the raw material melt in the crucible, the raw material supply apparatus including the raw material supply pipe having a very simple structure is used. The supply speed can be slowed down and the crucible can be damaged and the splash of the raw material melt can be suppressed to avoid adverse effects on the growth of the silicon single crystal. Therefore, the raw material supply apparatus and raw material supply method of the present invention can be widely used for the production of silicon single crystals.

It is sectional drawing which shows typically the whole structure of the single crystal pulling furnace by CZ method which has arrange | positioned the raw material supply apparatus of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the raw material supply method of this invention, (a) is the state before supplying a raw material to a raw material supply pipe, (b) is the state where the input raw material was once stopped in the contact part, (c ) Is a view showing a state in which the contact is released and the raw material is put into the crucible. It is a figure which shows the silicon ring attached to the front-end | tip of the raw material supply pipe | tube of the raw material supply apparatus of this invention, and its attachment state, (a) is sectional drawing after attachment, (b) is a perspective view of a silicon ring, (c) FIG. 3 is a side view of a silicon ring. It is a figure which shows typically the longitudinal cross-section of the front-end | tip part vicinity of the raw material supply pipe | tube of the raw material supply apparatus of this invention.

Explanation of symbols

1: Crucible 1a: Quartz crucible 1b: Graphite crucible 2: Support shaft 3: Heater 4: Heat insulating material 5: Raw material melt 6: Raw material supply hopper 7: Raw material supply pipe 7a, 7b: Oblique pipe 8: Cylindrical silicon 9: Pulling shaft 10: Hanging jig 11: Raw material 12: Silicon ring

Claims (5)

A raw material supply apparatus that is used for growing a single crystal by the Czochralski method and additionally charges or recharges a solid material in the form of agglomerates to a raw material melt in a crucible,
A portable raw material supply hopper for storing solid raw materials to be charged into the crucible;
A raw material supply pipe for charging the solid raw material in the raw material supply hopper into the crucible;
A raw material supply apparatus, comprising: a mechanism for temporarily stopping the raw material to be charged at a tip of a raw material supply pipe and then charging the raw material.   After stopping the raw material to be charged at the front end of the raw material supply pipe, the mechanism for charging is arranged near the front end of the raw material supply pipe and is configured to be movable up and down, and the front end opening of the raw material supply pipe The raw material charged at the contact portion is temporarily stopped, and then the stop is gradually raised to release the contact between the front end opening of the raw material supply pipe and the surface of the stop, and the raw material is placed in the crucible. The raw material supply apparatus according to claim 1, wherein the raw material supply apparatus is configured so as to be charged into the container.   The raw material supply apparatus according to claim 2, wherein the stopping object is cylindrical silicon, and a surface of the stopping object is a cylindrical surface of cylindrical silicon. When growing a single crystal by the Czochralski method, a raw material supply method for charging or recharging a raw material melt in a crucible to a solid material in the form of agglomerates,
The solid raw material discharged from the portable raw material supply hopper to the raw material supply pipe is temporarily stopped at the contact portion between the front end opening of the raw material supply pipe and the surface of the stopped object, and deposited on the raw material supply pipe.
Next, the stopper is gradually raised to release contact between the tip opening of the raw material supply pipe and the surface of the stopper, and the raw material is fed into the crucible. The raw material supply method according to claim 4, wherein the stopping object is cylindrical silicon, and a surface of the stopping object is a cylindrical surface of cylindrical silicon.

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