JP2008019133A - Crystal production apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crystal production apparatus by which single crystals and polycrystals can continuously, easily and inexpensively be produced with high quality. <P>SOLUTION: A raw material-charged crucible body 14 is disposed in a heating furnace 11 and is kept at a temperature equal to or higher than the melting point of the raw material while preventing oxidation in an inert gas atmosphere. After refining the raw material by rotating a stirrer 102, the refined material melt 92 is made to flow down from a through-hole 17 formed at the bottom of the crucible body 14 into a storage tank arranged at the lower part of the crucible body 14. The downflow melt 92 is brought into contact with the upper surface of a seed crystal plate 101 mounted on a lifting table 31 in the lower part of the crucible body 14. A crystal is grown by lowering the seed crystal plate 101 together with the lifting table 31 in the above contact state. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a crystal manufacturing apparatus, and more particularly to a manufacturing apparatus for manufacturing a single crystal or polycrystal suitable for mass production.

Silicon processed products are used in semiconductors, liquid crystals, optical communication devices, and the like. This processed silicon product is manufactured by almost four types of methods, namely polycrystalline (thermal reduction method, casting method, electromagnetic casting method) and single crystal (CZ method), and is used properly according to the application.
By the way, the characteristics of polycrystalline and single crystal silicon are listed.
(1) Polycrystalline silicon (thermal reduction method)
It is a rod-like polycrystal produced by repetitively distilling raw material silane trichloride in a high-precision distillation column and using a separately purified hydrogen as a reducing agent in a large reduction furnace. It is used as a raw material for semiconductor wafers and has a very high purity of 9N to 11N.
(2) Polycrystalline silicon (cast method)
It is ingot-shaped polycrystalline silicon obtained by melting polycrystalline silicon produced by a thermal reduction method with a crucible, and solidifying it in a mold. By using a large crucible, it is possible to manufacture ingots up to a diameter of 420φ.
(3) Polycrystalline silicon (electromagnetic casting method)
It is an ingot-shaped polycrystalline silicon obtained by melting polycrystalline silicon produced by a thermal reduction method with a high-frequency induction coil and continuously solidifying it without electromagnetic contact with a crucible.
Compared with a method using a quartz crucible or the like, it is characterized in that an ingot with high productivity can be obtained.
(4) Single crystal silicon (CZ method)
Polycrystalline silicon produced by the thermal reduction method is melted with a quartz crucible and pulled up by the CZ method (Czochralski method) to form a single crystal silicon rod.
The semiconductor silicon wafer is manufactured by slicing the single crystal silicon rod.

However, the thermal reduction method has a large equipment, and the casting method and the electromagnetic casting method have a problem that the quality is difficult to stabilize because they are molded in a mold, and the Czochralski method breaks at the top of the ingot when it is pulled up. In order to make it difficult, it is necessary to make the suspension mechanism have a special structure, and there is a problem that it is generally more expensive than a crystal manufacturing apparatus by other methods.

Similarly to this invention, as a crystal manufacturing method for lowering seed crystals, as described in JP-A-11-240789 (see Patent Document 1) and WO99 / 063132 (see Patent Document 2), an electric furnace is used. In a state where a crucible for melting the raw material is arranged and maintained at a temperature equal to or higher than the melting point of the raw material, the upper end of the seed crystal is in contact with the raw material melt leaked from the pores formed at the bottom of the crucible. There is known a single crystal manufacturing apparatus for growing a crystal by pulling down a seed crystal while rotating it.
Japanese Patent Laid-Open No. 11-240789 WO99 / 063132

However, in the above-described pulling-down method, the flow rate of the melt flowing out from the pores at the bottom of the platinum crucible changes with the amount of melt in the crucible, so that the high quality having a large number of straight body portions, that is, portions having a uniform diameter. There was a problem that it was difficult to obtain a single crystal. In other words, when the amount of melt in the crucible is large, the flow rate of the melt flowing out from the pores is also large, but the flow rate decreases as the amount of melt in the crucible decreases, so that the straight body portion is increased. In order to obtain it, it was necessary to gradually reduce the growth rate from the start to the end of the growth, and it was difficult to control the temperature in the furnace and control the rate of pulling down the seed crystals.
Moreover, in any growth method, the raw material volume in the crucible is limited, and there are restrictions on the dimensions (length, diameter, etc.) of the crystal to be grown. For example, silicon ingots are manufactured continuously. I couldn't.
The present invention was devised to solve the above problems, and it is an object of the present invention to provide a crystal manufacturing apparatus capable of manufacturing single crystals and polycrystals continuously at low cost and with good quality.

In order to solve the above-described problem, the crystal manufacturing apparatus according to the first aspect of the present invention includes a crucible body containing raw materials in a heating furnace, and prevents the oxidation in an inert gas atmosphere while preventing the oxidation. After maintaining the temperature above the melting point of the raw material and purifying by rotary stirring, the purified raw material melt is allowed to flow from the through hole formed at the bottom of the crucible body to the storage tank located at the bottom of the crucible body. It is what.
The crystal manufacturing apparatus according to the second aspect of the present invention has a crucible main body containing raw materials placed in a heating furnace and keeps it at a temperature equal to or higher than the melting point of the raw materials while preventing oxidation in an inert gas atmosphere. The raw material melt flowing down from the through hole formed in the bottom of the crucible body after being purified by rotary stirring is in contact with the upper surface of the seed crystal plate mounted on the lifting table at the bottom of the crucible body, together with the lifting table A crystal manufacturing apparatus for growing a crystal by lowering a seed crystal plate,
A raw material melting tank for melting the raw material to produce a raw material melt;
A raw material supply means for supplying the raw material to the raw material melting tank;
Raw material melt introduction means for introducing the raw material melt in the raw material melting tank into the crucible body,
A rotating stirring means for rotating and stirring the raw material melt in the crucible body;
Temperature control means for adjusting the temperature of the area where the seed crystal plate is lowered together with the lifting table at the bottom of the crucible body,
It is characterized by this.
The crystal manufacturing apparatus according to the invention described in claim 3 is arranged such that a crucible body containing a raw material is placed in a heating furnace and kept at a temperature equal to or higher than the melting point of the raw material while preventing oxidation in an inert gas atmosphere. The raw material melt flowing down from the through hole formed in the bottom of the crucible body after being purified by rotary stirring is in contact with the upper surface of the seed crystal plate mounted on the lifting table, and the seed crystal plate is mounted together with the lifting table. A crystal manufacturing apparatus for growing crystals by lowering; and
Seed crystal plate supply means for transporting the seed crystal plate on a lifting table in a heating furnace;
And an ingot discharging means for transporting the ingot grown on the seed crystal plate on the lifting table in the heating furnace to the cooling section.
In the crystal manufacturing apparatus according to the invention of claim 4, the heating furnace includes:
The outer wall,
A heating device provided inside the outer wall;
A crucible body made of a heat-resistant metal disposed inside the heating device and a ceramic lining disposed inside the heat-resistant metal crucible body,
It is characterized in that the through-hole is opened and closed by raising and lowering the rod-shaped on-off valve from the upper part of the crucible body toward the through-hole formed in the bottom.
In the crystal manufacturing apparatus according to the invention described in claim 5, the rotary stirring means is
A tubular body surrounding the periphery of the rod-shaped on-off valve of the crucible body,
A stirring blade formed at the bottom of the tubular body;
A rotation drive mechanism attached to the upper part of the cylindrical body,
The raw material melt in the crucible body is appropriately rotated and stirred.

As described above, according to the crystal manufacturing apparatus according to the first aspect of the present invention, the crucible main body containing the raw material is arranged in the heating furnace, and this is prevented while oxidizing the raw material in an inert gas atmosphere. By maintaining the temperature above the melting point and purifying by rotary stirring, the purified raw material melt is allowed to flow from the through hole formed at the bottom of the crucible body to the storage tank located at the bottom of the crucible body. The raw material melt can be appropriately rotated and agitated to increase the purity of the raw material melt, and high quality crystals can be obtained quickly.
As described above, according to the crystal manufacturing apparatus according to the second aspect of the present invention, the crucible main body containing the raw material is placed in the heating furnace, and the raw material is prevented from being oxidized in an inert gas atmosphere. After maintaining the temperature above the melting point and purifying by rotary stirring, the raw material melt flowing down from the through hole formed in the bottom of the crucible body was brought into contact with the upper surface of the seed crystal plate mounted on the lifting table at the bottom of the crucible body. In this state, the seed crystal plate is lowered together with the lifting table to grow the crystal, thereby appropriately rotating and stirring the raw material melt in the crucible body to increase the purity of the raw material melt and to grow high quality crystals. Can be done quickly.
Moreover, according to the crystal manufacturing apparatus according to the third aspect of the present invention, the seed crystal plate is transported to the heating furnace, the ingot is grown on the seed crystal plate in the heating furnace, and the ingot is transported to the cooling unit. Further, it is characterized in that the conveyance in the cooling unit can be performed continuously.
According to the crystal manufacturing apparatus of the fourth aspect of the present invention, a heating furnace having excellent durability can be obtained.
According to the crystal manufacturing apparatus according to the invention of claim 5, since the raw material melt in the crucible body can be efficiently rotated and stirred, a high-quality ingot having a higher degree of purification can be provided. To do.

Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings.
FIG. 1 is a schematic view showing an example of an embodiment of a crystal manufacturing apparatus according to the present invention. In this example, a case where a silicon single crystal is manufactured will be described. FIG. 2 is a schematic view showing an example of a means for supplying a raw material melt to the crystal manufacturing apparatus according to the present invention. FIG. 3 is a schematic perspective view showing the main part of the crystal manufacturing apparatus according to the present invention. FIG. 5 is a schematic perspective view showing another example of the main part of the crystal manufacturing apparatus according to the invention, and FIG. FIG. 6 is a schematic view showing another example of the embodiment of the crystal manufacturing apparatus according to the present invention.

In FIG. 1, a heating furnace 11 includes a cylindrical outer wall 12 made of a heat-resistant material, a heating device 13 in which high-frequency heating means and the like disposed therein are disposed in a cylindrical shape, and a heating apparatus 13 disposed therein. A cylindrical crucible main body 14 made of a molybdenum-lanthanum alloy and a heat-resistant lining 15 made of silicon nitride or the like disposed from the inner wall to the bottom thereof. Reference numeral 16 denotes a rod-like on-off valve that can be raised and lowered toward the through-hole 17 formed at the bottom of the lining 15 and is fitted into a through-hole 19 at the center of the upper lid 18 attached on the cylindrical outer wall 12. The rod-shaped on-off valve 16 and the upper lid 18 are also made of a heat resistant material made of silicon nitride or the like. In the figure, 20-1 is a supply port for the raw material melt 92, and 20-2 is a supply nozzle for resistance adjustment. Reference numeral 21 denotes a supply port for an inert gas, for example, argon gas, for preventing oxidation during heating by the heating device 13, and 22 is an argon gas discharge port.
Around the rod-shaped on-off valve 16, there is mounted a rotary stirring means comprising a cylindrical main body 101 attached so as to wrap it and a stirring blade 102 formed at the lower part of the cylindrical main body 101. As a rotational drive mechanism of the stirring blade 102, a gear or pulley 103 is attached to the upper part of the cylindrical main body 101, and the driving force of the drive motor 104 installed on the heating furnace 11 is transmitted via the gear or drive belt 105. The configuration is adopted.
Therefore, by driving the drive motor 104 and rotating the stirring blade 102 together with the cylindrical main body 101, the raw material melt 92 in the crucible main body 14 can be rotated and stirred, and oxygen, carbon, nitrogen, etc. By moving the light element impurities resulting from the above to the upper part of the crucible body 14, the purity of the raw material melt 92 is greatly improved, and a high-quality ingot can be obtained.
Reference numeral 106 denotes an overload prevention spring attached to the upper end of the rod-shaped on-off valve 16.
At the bottom of the crucible main body 14, an area 23 for lowering the seed crystal plate 101 together with a lifting table 31 to be described later is provided at the bottom of the outer wall 12, and temperature management means for adjusting the temperature of this area 23, for example, A heating device 24 capable of temperature control is attached. Reference numeral 25 is an area outer wall, 26 is an area crucible, and 27 is a heat resistant lining.

The elevating table 31 can be raised and lowered by an elevating cylinder 33 housed in an operation chamber 32 disposed at the lower part of the heating furnace 11.
That is, the operation chamber 32 is opened at the top, and the elevating table 31 is fitted into the bottom opening 34 of the area 23 provided at the lower portion of the crucible body 14. A shutter 36 is attached to the side wall opening 35 so that the side wall opening 35 can be freely opened and closed. A bottom opening 37 through which the elevating cylinder 33 advances and retreats is disposed at the bottom of the operation chamber 32.
The elevating cylinder 33 has a base 38 fixed to the upper part thereof, and the elevating table 31 is stacked on the base 38 via a transport base 39. The transfer table 39 includes two ceramic plates 40 and 41 arranged at a predetermined interval via a spacer 42, and can be slid by a ball bearing 43 between the base plate 38 and the ball bearing 43. Temporary fixing holes 44 are provided at positions where they fit.
A cooling material 45 made of a metal having a good thermal conductivity, for example, copper, is embedded in the substantially center of the lifting table 31, and this is cooled by air cooling or the like, so that the raw material melt 92 on the seed crystal plate 101 is cooled. A temperature gradient is applied, and the crystal is grown from the central portion of the raw material melt 92 so that the impurities move to the peripheral portion. In this way, the peripheral portion containing impurities is cut from the obtained ingot 102 and sent to the subsequent process.
46 is a cylinder protective cover disposed around the elevating cylinder 33, 47 is a discharge cylinder that pushes the conveying table 39 toward the side wall opening 35 at a position where the elevating cylinder 33 is lowered, 48 is an argon gas supply port, and 49 is It is a circulation pipe for water cooling.
The coolant 45 installed at substantially the center of the lift table 31 can be air-cooled by supplying argon gas from the supply port 48 through the two ceramic plates 40 and 41 of the transfer table 39. Reference numeral 50 denotes an air cooling vent provided in the upper ceramic plate 40.
Further, a cooling unit 51 is disposed on the side of the side wall opening 35 of the operation chamber 32, and a transport roller 52 for transporting the elevating table 31 on which the silicon ingot 102 is mounted together with the transport table 39 to the bottom is also provided. A helium gas supply port 53 is provided at the top.
Reference numeral 54 denotes an inspection window (sensor part) for the heating furnace 11 for monitoring the amount, state, temperature, etc. of the raw material melt 92, and 55 an inspection window for the area 23 where the seed crystal plate 101 is lowered. The (sensor unit) is for monitoring the generation state, temperature, etc. of the ingot 102.

FIG. 2 is a view for explaining a means for supplying the raw material melt to the crystal manufacturing apparatus of the present invention. The raw material melting tanks for melting the raw material 91 to produce the raw material melt 92 include upper, middle and lower stages. The upper raw material melting tank 62-1 that forms the raw material melt by melting the raw material of silicon introduced from the hopper 61 or melting the granular raw material, and the upper raw material melting It consists of a middle pair of raw material melting tanks 62-2 and 62-3 for alternately charging the raw material melt from the tank 61, and a lower raw material melting tank 62-4 for sequentially charging the distributed raw material melt. Yes. Each raw material melting tank 62-1 to 62-4 is a heating in which a container-shaped outer wall 63 made of a heat-resistant material having an open top and a high-frequency heating means disposed inside thereof are arranged in a cylindrical shape. The apparatus 64 includes a cylindrical crucible main body 65 made of molybdenum-lanthanum alloy and a heat resistant lining 66 made of silicon nitride or the like provided from the inner wall to the bottom. Reference numeral 67 denotes a rod-like on-off valve that can be raised and lowered toward the through hole 68 formed in the bottom of the lining 66 and is fitted in the through hole 70 in the center of the upper lid 69 attached on the container-like outer wall 63. The rod-shaped on-off valve 67, the upper lid 69, and the like are also formed of a heat resistant material made of silicon nitride or the like. In the figure, 71 is a resistance adjusting material supply port, 72 is a communication pipe for communicating between the through hole 68 of each raw material melting tank 62-1 to 62-4 and the upper lid 69, and 73 is each raw material melting tank 62-1 to 62-1. 62-4 inspection windows (sensor parts), 74 is a shutter of the hopper 61. Note that a supply port and a discharge port for an inert gas such as argon gas are omitted.

3 and 4 show an example of the main part of the crystal manufacturing apparatus according to the present invention. From the top, the heating furnace 11, the crystal growth area 23, the lift table 31 on which the seed crystal plate 101 is mounted, and the lift cylinder 33.
The heating furnace 11 includes a cylindrical outer wall 12 and a cylindrical crucible body 14 (other constituent materials such as a heating device are omitted). Reference numeral 16 denotes a rod-shaped on-off valve.
The area 23 for lowering the seed crystal plate together with the lifting table 31 is also composed of an area outer wall 25 and an area crucible 26 (other constituent materials such as a temperature adjusting device are omitted).
The lifting table 31 is held by a lifting cylinder 33 via a transfer table 39 so as to be movable up and down.
In the example of FIG. 3, the area 23 is formed in a cylindrical shape according to the circular seed crystal plate 101, and in the example of FIG. 4, the area 23 is formed in a rectangular tube shape according to the square seed crystal plate 101.
Therefore, an ingot having a shape corresponding to the circular seed crystal plate 101 or the square seed crystal plate 101 can be obtained, and these apparatuses can be appropriately combined depending on what shape of the ingot is obtained.
In addition, the size and thickness of the ingot to be obtained can be changed depending on the size of the area 23 and the amount of the raw material melt 92 charged into the heating furnace 11. Ingots with various thicknesses, such as larger or smaller ones, and various thicknesses, can be obtained from those substantially equal to the size in the outer diameter direction.

When using this crystal manufacturing apparatus, the following operations are performed.
A predetermined amount of raw material 91 is charged into the upper raw material melting tank 62-1 from the hopper 61 shown in FIG. 2 and melted to generate a raw material melt 92. Next, the raw material melt 92 is alternately charged from the upper raw material melting tank 61 into the pair of middle raw material melting tanks 62-2 and 62-3. Next, the raw material melt 92 distributed to the raw material melting tanks 62-2 and 62-3 is sequentially introduced into the lower raw material melting tank 62-4. Accordingly, the raw material melt 92 is quickly supplied to the heating furnace 11 from the lower raw material melting tank 62-4. In these raw material melting tanks 62-1 to 62-4 and the heating furnace 11, the raw material 91 and the raw material melt 92 are heated to a temperature higher than the melting point (for example, 1450 ° C.), as shown in FIG. In addition, the seed crystal plate 101 is mounted on the lifting table 31, and the lifting table 31 is fitted in the bottom opening 34 of the area 23 provided in the lower part of the crucible body 14 in this state.
The raw material melt 92 supplied to the heating furnace 11 flows down onto the seed crystal plate 101 on the elevating table 31 by raising the rod-shaped on-off valve 16 and opening the through-hole 17, and according to a predetermined amount of raw material. Laminated to thickness.

The raw material melt 92 laminated to a predetermined thickness on the seed crystal plate 101 descends in the area 23 together with the lifting table 31 at a predetermined speed (for example, 0.75 mm / h), with the coolant 45 as the center. Crystals gradually precipitate toward the periphery according to a slight temperature gradient with respect to the inside of the heating furnace 11.
After the precipitation of the crystals is finished, the lifting table 31 with the ingot lowered to the lowermost part of the operation chamber 32 by the lifting cylinder 33 is discharged from the side wall opening 35 together with the transport base 39 to the cooling unit 51 by the discharge cylinder 46 and cooled. In the part 51, the sheet is conveyed to a predetermined place by the conveyance roller 52. The ingot cooled during that time becomes a high-quality silicon ingot.

FIG. 5 shows from the loading of the seed crystal plate into the heating furnace to the growth of the ingot onto the seed crystal plate in the heating furnace and the carrying out of the ingot to the cooling section.
In the drawing, a supply path 81 for supplying the seed crystal plate 101 is formed on the side of the heating furnace 11, and the seed crystal plate 101 is fed into the heating furnace 11 by the supply cylinder 83 by opening the shutter 82 provided therebetween. It is. Of course, at that time, the lifting table 31 is lowered to the lowermost part of the operation chamber 32, and the seed crystal plate 101 is mounted on the lifting table 31 (not shown).
The raw material melt heated in the inert gas atmosphere in the heating furnace 11 is caused to flow down from the through hole 17 formed in the bottom of the crucible body 14 and is brought into contact with the upper surface of the seed crystal plate 101 mounted on the lifting table 31. In this state, the seed crystal plate 101 is lowered together with the lifting table 31 to grow a crystal (not shown), and the obtained ingot 102 is carried out to a slow cooling chamber 84 provided on the other side of the heating furnace 11. . That is, the shutter 85 between the heating furnace 11 and the gradual chamber 84 is opened, and the lifting table 31 with the ingot is pushed out together with the transport table 39 into the gradual chamber 84 by the extrusion cylinder 86. The slow chamber 84 is adjusted so that a suitable temperature gradient for crystal growth can be given to the ingot 102.
Next, the shutter 87 is opened to the cooling part 51 formed on the side of the slow cooling chamber 84 and the ingot is pushed out to the cooling part 51 cooled by natural heat radiation by the discharge cylinder 46.
The ingot 102 is carried out together with the transport table 39 to a predetermined place.

Although the case where the crystal manufacturing apparatus of the present invention is a growth furnace has been described in FIG. 1, the case where the crystal manufacturing apparatus of the present invention is a refining furnace will be described with reference to FIG.
In FIG. 6, a heating furnace 11 includes a cylindrical outer wall 12 made of a heat-resistant material, a heating device 13 in which high-frequency heating means and the like disposed therein are disposed in a cylindrical shape, and a heating apparatus 13 disposed therein. A cylindrical crucible main body 14 made of a molybdenum-lanthanum alloy and a heat-resistant lining 15 made of silicon nitride or the like disposed from the inner wall to the bottom thereof. Reference numeral 16 denotes a rod-like on-off valve that can be raised and lowered toward the through-hole 17 formed at the bottom of the lining 15 and is fitted into a through-hole 19 at the center of the upper lid 18 attached on the cylindrical outer wall 12. The rod-shaped on-off valve 16 and the upper lid 18 are also made of a heat resistant material made of silicon nitride or the like. In the figure, 20-1 is a supply port for the raw material melt 92, and 20-2 is a supply nozzle for resistance adjustment. Reference numeral 21 denotes a supply port for an inert gas, for example, argon gas, for preventing oxidation during heating by the heating device 13, and reference numeral 22 denotes a discharge port for argon gas.

Around the rod-shaped on-off valve 16, there is mounted a rotary stirring means comprising a cylindrical main body 101 attached so as to wrap it and a stirring blade 102 formed at the lower part of the cylindrical main body 101. As a rotational drive mechanism of the stirring blade 102, a gear or pulley 103 is attached to the upper part of the cylindrical main body 101, and the driving force of the drive motor 104 installed on the heating furnace 11 is transmitted via the gear or drive belt 105. The configuration is adopted.
Therefore, by driving the drive motor 104 and rotating the stirring blade 102 together with the cylindrical main body 101, the raw material melt 92 in the crucible main body 14 can be rotated and stirred, and oxygen, carbon, nitrogen, etc. By moving the light element impurities resulting from the above to the upper part of the crucible body 14, the purity of the raw material melt 92 is greatly improved, and a high-quality ingot can be obtained.
Reference numeral 106 denotes an overload prevention spring attached to the upper end of the rod-shaped on-off valve 16.
An area 23 through which the raw material melt 92 flows down is provided at the bottom of the outer wall 12 at the lower part of the crucible body 14, and temperature management means for adjusting the temperature of the area 23, such as a heating device capable of temperature control, is provided around the area 23. 24 is attached. Reference numeral 25 is an area outer wall, 26 is an area crucible, and 27 is a heat resistant lining.

In a storage tank which is arranged at the lower part of the crucible main body 14 and is composed of the area outer wall 25, the area crucible 26, and the heat resistant lining 27, a raw material melt 92 having a greatly improved degree of purification in the crucible main body 14. Since the water flows down and is stored, a high-quality ingot is obtained.
In this case, the obtained ingot is supplied to a growth furnace or a refining furnace for further purification and used to obtain a higher quality ingot.

In the above embodiment, the case where a silicon single crystal is manufactured has been described as an example. However, the crystal manufacturing apparatus having the above configuration is not only a silicon single crystal but also a silicon polycrystal, a rutile used as a material for an optical isolator, It can also be applied to the production of single crystals such as BGO and BSO used as scintillator materials, CLBO as a kind of nonlinear optical material, and LN and LT known as piezoelectric / optical materials.

It is the schematic which shows an example of embodiment of the crystal manufacturing apparatus based on this invention. In this example, a case where a silicon single crystal is manufactured will be described. It is the schematic which shows an example of the supply means of the raw material melt to the crystal manufacturing apparatus based on this invention. It is a schematic perspective view which shows the principal part of the crystal manufacturing apparatus based on this invention. It is a schematic perspective view which shows the other example which concerns on the principal part of the crystal manufacturing apparatus based on this invention. It is the schematic which shows from the carrying in of a seed crystal plate to the heating furnace to the growth of the ingot on the seed crystal plate in a heating furnace, and carrying out to the cooling part of an ingot. It is the schematic which shows the other example of embodiment of the crystal manufacturing apparatus based on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Heating furnace 12 Outer wall 13 Heating apparatus 14 Crucible body 15 Inner lining 16 Rod-like on-off valve 17 Through hole 18 Top cover 19 Through hole 20-1 Supply port 20-2 Resistance adjustment material supply nozzle 21 Argon gas supply port 22 Argon gas exhaust Exit 23 Area 24 Heating device 25 Area outer wall 26 Area part crucible 27 Inner lining 31 Lifting table 32 Operation chamber 33 Lifting cylinder 34 Bottom opening 35 Side wall opening 36 Shutter 37 Bottom opening 38 Base 39 Transfer platform 40, 41 Ceramic plate 42 Spacer 43 Ball bearing 44 Temporary fixing hole 45 Coolant 46 Cylinder protection cover 47 Discharge cylinder 48 Argon gas supply port 49 Circulation pipe 50 Vent hole 51 Cooling unit 52 Transport roller 53 Helium gas supply port 54 Inspection window (sensor unit)
55 Inspection window (sensor part)
61 Hopper 62-1, 62-2, 62-3, 62-4 Raw Material Melting Tank 63 Outer Wall 64 Heating Device 65 Crucible Body 66 Inner Line 67 Rod Opening Valve 68 Through Hole 69 Top Cover 70 Through Hole 71 Resistance Adjusting Material Supply Port 72 Communication pipe 73 Inspection window (sensor part)
74 Shutter 81 Supply path 82 Shutter 83 Supply cylinder 84 Slow cooling chamber 85 Shutter 86 Extrusion cylinder 87 Shutter 91 Raw material 92 Raw material melt 101 Tubular main body 102 Stirring 103 Gear or pulley 104 Drive motor 105 Gear or drive belt 106 Overload prevention spring

Claims (5)

Place the crucible body containing the raw material in the heating furnace, keep it at a temperature above the melting point of the raw material while preventing oxidation in an inert gas atmosphere, purify it by rotary stirring, and then form it at the bottom of the crucible body A crystal production apparatus characterized in that the refined raw material melt is allowed to flow from a through hole formed into a storage tank disposed at the bottom of the crucible body. Place the crucible body containing the raw material in the heating furnace, keep it at a temperature above the melting point of the raw material while preventing oxidation in an inert gas atmosphere, purify it by rotary stirring, and then form it at the bottom of the crucible body Production of crystals by lowering the seed crystal plate together with the lifting table while the raw material melt flowing down from the through hole is in contact with the upper surface of the seed crystal plate mounted on the lifting table at the lower part of the crucible body A device,
A raw material melting tank for melting the raw material to produce a raw material melt;
A raw material supply means for supplying the raw material to the raw material melting tank;
Raw material melt introduction means for introducing the raw material melt in the raw material melting tank into the crucible body,
A rotating stirring means for rotating and stirring the raw material melt in the crucible body;
Temperature control means for adjusting the temperature of the area where the seed crystal plate is lowered together with the lifting table at the bottom of the crucible body,
A crystal manufacturing apparatus. Place the crucible body containing the raw material in the heating furnace, keep it at a temperature above the melting point of the raw material while preventing oxidation in an inert gas atmosphere, purify it by rotary stirring, and then form it at the bottom of the crucible body A crystal production apparatus for growing a crystal by lowering the seed crystal plate together with the lifting table in a state where the raw material melt flowing down from the through hole is in contact with the upper surface of the seed crystal plate mounted on the lifting table;
Seed crystal plate supply means for transporting the seed crystal plate on a lifting table in a heating furnace;
A crystal manufacturing apparatus comprising: an ingot discharging means for transporting an ingot grown on a seed crystal plate on a lifting table in a heating furnace to a cooling unit. The heating furnace
The outer wall,
A heating device provided inside the outer wall;
A crucible body made of a heat-resistant metal disposed inside the heating device and a ceramic lining disposed inside the heat-resistant metal crucible body,
The crystal manufacturing apparatus according to any one of claims 1 to 3, wherein a through-hole is opened and closed by raising and lowering a rod-shaped on-off valve from the upper part of the crucible body toward the through-hole formed in the bottom. Rotating stirring means
A tubular body surrounding the periphery of the rod-shaped on-off valve of the crucible body,
A stirring blade formed at the bottom of the tubular body;
A rotation drive mechanism attached to the upper part of the cylindrical body,
The crystal manufacturing apparatus according to any one of claims 1 to 4, wherein the raw material melt in the crucible body is appropriately rotated and stirred.

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