JP4105163B2 - Thin plate manufacturing apparatus and thin plate manufacturing method - Google Patents

Description

  The present invention relates to a thin plate manufacturing apparatus and a thin plate manufacturing method, and more specifically to a silicon thin plate manufacturing apparatus and a silicon thin plate manufacturing method.

As one conventional thin plate manufacturing apparatus, for example, a “crystal sheet manufacturing method, its manufacturing apparatus, and solar cell” disclosed in Japanese Patent Application Laid-Open No. 2001-247396 can be cited.
This "crystal sheet manufacturing apparatus" includes a substrate having a main surface on which a crystal sheet is to be formed, a container for holding a melt, and a main surface of the substrate coming into contact with the melt and then leaving the melt. A movable member that holds the substrate for moving the substrate and a cooling means for cooling the movable member are provided.
In the crystal sheet manufacturing apparatus configured as described above, the main surface of the substrate on which the crystal sheet is formed is cooled via the movable member cooled by the cooling means, and the crystal sheet is solidified and grown on the main surface of the substrate. It becomes possible.
As shown in FIG. 8, in the “crystal sheet manufacturing apparatus”, a heating chamber made of a heat insulating material is provided in the main chamber 801, and the heater 804 using resistance heating is used in the crucible 809. Can be heated above the melting point. By continuously producing the crystal sheet, the amount of the melt is reduced, so that a raw material charging port 806 is provided to add the raw material.
However, in the above-mentioned “conventional crystal sheet manufacturing method and manufacturing apparatus and solar cell” in the above prior art, the movable member 802 for immersing the substrate 803 in the melt 808 and the material input port for adding the material Since 806 is adjacent to the main chamber 801, when adding a raw material, it is easy to interfere with the board | substrate 803 and the movable member 802, and workability | operativity is bad. Further, in order to avoid the interference between the movable member 802 and the raw material input port 806, if the installation positions are to be separated from each other, it is necessary to increase the size of the crucible 809, which causes a new problem of increased supply power. Furthermore, the increase in crucible size increases the amount of melt, which increases the heat capacity of the melt. Therefore, after changing the preset temperature of the melt, the time until the melt temperature stabilizes at the preset temperature (melt temperature stabilization time) increases, resulting in a problem that productivity deteriorates.
As another example of a conventional thin plate manufacturing apparatus, for example, “thin plate manufacturing apparatus and thin plate manufacturing method” disclosed in Japanese Patent Application Laid-Open No. 2003-59849 can be cited.
This thin plate manufacturing apparatus has a substrate transport mechanism that is movable in the horizontal direction and the vertical direction and has a mechanism for tilting the substrate, and can move the substrate immersed in the melt in a free trajectory. However, details about the raw material charging mechanism are not described, and after the improvement of the interference between the substrate immersion mechanism and the raw material charging mechanism at the time of raw material charging or after changing the set temperature of the melt, the melt temperature becomes the set temperature. The problem of shortening the time until stabilization (melt temperature stabilization time) has not been solved.

The thin plate manufacturing apparatus of the present invention is a thin plate manufacturing apparatus for manufacturing a thin plate on the surface of a substrate by immersing the substrate in a melt in a crucible, and is provided with a crucible moving mechanism.
By providing the crucible moving mechanism, it is possible to place the crucible in the dipping position when producing a thin plate, and to move the crucible to a position different from the dipping position when dissolving the additional raw material. Raw materials can be added without interference. Moreover, since it is not necessary to increase the crucible size, the power consumption can be reduced and the melt temperature stabilization time can be shortened as compared with the case where the crucible size is increased.
Moreover, the thin plate manufacturing apparatus of the present invention includes a raw material charging mechanism for charging an additional raw material into a crucible.
By providing the raw material charging mechanism, it is possible to add the raw material consumed by the production of the thin plate while the apparatus is in operation.
Moreover, the crucible moving mechanism of the thin plate manufacturing apparatus of the present invention is characterized by having an alignment mechanism for aligning the crucible at a place where the substrate is immersed in the melt.
By accurately aligning the position of the crucible using the alignment mechanism with the immersion position, a thin plate can be produced without the substrate immersion mechanism for immersing the substrate in the melt without interfering with the crucible wall.
The thin plate manufacturing apparatus of the present invention is characterized in that it has a mechanism for controlling the moving speed and / or speed change of the crucible so that the melt does not spill from the crucible during the movement of the crucible.
If the moving speed of the crucible is sufficiently slow, it is possible to prevent the melt from spilling from inside the crucible by controlling only the moving speed, which eliminates the need for cleaning the spilled melt and enables continuous operation of the equipment. Become. The same effect can be obtained by controlling only the movement speed change. Further, when the moving speed of the crucible is high to some extent, by controlling both the moving speed and the speed change, the melt can be prevented from spilling from the crucible and the time required for the crucible movement can be shortened.
Moreover, the thin plate manufacturing apparatus of the present invention is characterized by having a heat insulating mechanism between the crucible moving mechanism and the crucible.
By having the heat insulation mechanism, the temperature of the crucible moving mechanism can be prevented from becoming too high due to the heat from the crucible held at a high temperature, and the crucible moving mechanism can be operated continuously.
The thin plate manufacturing apparatus of the present invention is characterized by having a cooling mechanism between the crucible moving mechanism and the crucible.
By having the cooling mechanism, the temperature of the crucible moving mechanism can be prevented from becoming too high due to the heat from the crucible held at a high temperature, and the crucible moving mechanism can be operated continuously.
The thin plate manufacturing apparatus of the present invention is characterized in that the raw material charging mechanism is installed at a position different from the substrate immersion mechanism for immersing the substrate in the melt.
By providing the raw material input mechanism at a position different from the substrate immersion mechanism, the apparatus can be operated without interference between the raw material input mechanism and the substrate immersion mechanism.
Further, the thin plate manufacturing apparatus of the present invention forms a thin plate when the crucible is located at a dipping position where the substrate dipping mechanism immerses the substrate in the melt, and the additional raw material when the crucible is located at a location different from the dipping position. It is characterized in that it is put into a crucible.
By forming the thin plate and adding the additional raw material at different positions, the raw material can be added without interfering with the substrate immersion mechanism.
Further, the thin plate manufacturing apparatus of the present invention is characterized in that an additional raw material is charged into a crucible in a sub chamber capable of maintaining an atmosphere independent of a main chamber having a substrate immersion mechanism.
By introducing and melting the additional raw material in a room different from the main room where the substrate immersion mechanism is located, it is possible to prevent contamination caused by the powder generated when the raw material is dissolved adhering to and around the substrate immersion mechanism. .
The thin plate manufacturing apparatus of the present invention is characterized in that the sub chamber has a raw material charging mechanism.
By providing the additional raw material charging mechanism in the sub chamber, the additional raw material can be charged without interfering with the substrate immersion mechanism provided in the main chamber.
Further, in the thin plate manufacturing apparatus of the present invention, the raw material input mechanism includes a raw material input chamber, a replacement mechanism for making the atmosphere in the raw material input chamber the same as the atmosphere in the sub chamber, and between the raw material input chamber and the sub chamber. And a partition mechanism for partitioning.
By charging additional raw materials into the raw material input chamber partitioned from the sub chamber by the partitioning mechanism, and replacing the air in the raw material input chamber with the same atmosphere as the sub chamber, additional raw materials can be added without disturbing the atmosphere in the sub chamber due to air contamination. Can be thrown in.
The thin plate manufacturing apparatus of the present invention is characterized by having at least two crucibles.
By having at least two crucibles, the tact time required for thin plate production can be shortened.
In addition, the thin plate manufacturing apparatus of the present invention is characterized by having the same number of crucible moving mechanisms as the number of crucibles.
By providing the same number of crucible moving mechanisms for a plurality of crucibles, settings relating to crucible movement can be made freely.
In addition, the thin plate manufacturing apparatus of the present invention is characterized by having the same number of raw material input mechanisms as crucibles.
By providing the same number of raw material charging mechanisms for a plurality of crucibles, settings relating to the charging of additional raw materials into the crucible can be made freely.
Moreover, the thin plate manufacturing apparatus of this invention can make a several crucible juxtapose in one subchamber.
By arranging a plurality of crucibles in one sub chamber, the apparatus configuration is simplified and the cost can be reduced.
In addition, the thin plate manufacturing apparatus of the present invention is characterized by having the same number of sub chambers as crucibles.
By providing the same number of sub-chambers as crucibles, it becomes possible to continue the immersion operation in the main chamber while performing the process of charging, melting, and stabilizing the temperature of the additional raw materials in an atmosphere independent of the main chamber. It is possible to prevent contamination caused by the powder generated at times adhering to the substrate immersion mechanism.
Furthermore, the thin plate manufacturing method of the present invention is a thin plate manufacturing method in which a thin plate is formed on the substrate surface by immersing the substrate held by the substrate immersing mechanism in the melt in the crucible, at a position different from the immersion position. The solid raw material in the crucible is heated and dissolved.
By adopting such a method, it is possible to perform the initial baking and melting of the solid raw material without thermally affecting the substrate immersion mechanism.
The thin plate manufacturing method of the present invention is characterized in that the place where the solid raw material is heated and melted is a sub-chamber capable of maintaining an atmosphere independent of the main chamber.
By adopting such a method, it is possible to prevent contamination due to the powder generated during the initial dissolution or initial baking of the solid raw material adhering to the substrate immersion mechanism.
Moreover, the thin plate manufacturing method of the present invention is characterized by including a step of adding an additional raw material to a crucible.
By adopting such a method, even when the amount of the solid raw material to be initially filled in the crucible is insufficient, the raw material can be added without interfering with the substrate immersion mechanism.
The method for producing a thin plate of the present invention includes a step of producing a thin plate at an immersion position, a step of moving a crucible to a raw material charging position, a step of adding an additional raw material to a crucible, a step of moving the crucible to a immersion position, It is characterized by having.
By adopting such a method, it is possible to produce a thin plate continuously for a long time.
The method for producing a thin plate of the present invention includes a step of producing a thin plate using one crucible at an immersion position, a step of moving one crucible to one raw material charging position, and a step of adding additional raw materials to one crucible. A step of moving one crucible to the immersion position, a step of producing a thin plate using another one crucible different from the one crucible at the immersion position, and another raw crucible as one raw material charging position. Comprises a step of moving to another different raw material charging position, a step of charging additional raw material into the other crucible, and a step of moving the other crucible to the immersion position. .
By adopting such a method, a thin plate can be continuously manufactured using a plurality of crucibles.
Further, in the method for producing a thin plate of the present invention, when performing a step of producing a thin plate using one crucible, a step of adding an additional raw material to another crucible and a step of adding the other raw material to the other crucible It is characterized by performing at least one of a step of heating and dissolving the additional raw material and a step of stabilizing the temperature of the melt held in the other crucible.
By adopting such a method, the tact time required for manufacturing the thin plate can be shortened.
In the thin plate manufacturing method of the present invention, when performing the step of moving one crucible to the dipping position, another one crucible different from one crucible is different from one raw material charging position. The step of moving to the raw material charging position is performed.
By adopting such a method, the tact time required for manufacturing the thin plate can be further shortened.

1-6 is the schematic of the thin plate manufacturing apparatus of this invention.
7A to 7C are tact comparison tables in comparative examples and Embodiments 1 to 5 of the present invention.
FIG. 8 is a schematic diagram of a conventional apparatus.
FIG. 9 is a schematic view of the substrate immersion mechanism.
FIG. 10 is a schematic view of the crucible moving mechanism.

Hereinafter, the thin plate manufacturing apparatus in each embodiment based on this invention is demonstrated, referring a figure.
(Substrate immersion mechanism)
The main chamber 101 includes a crucible 6 for storing the silicon melt 5 and a substrate immersion mechanism 4 for transferring the substrate 2 and immersing it in the silicon melt 5. As the substrate immersion mechanism 4, any mechanism such as a mechanism using a guide rail, a mechanism using a rotating body, a mechanism using a structure such as a robot arm may be used. A substrate immersion mechanism 901 shown in FIG. 9 includes an elevating mechanism 910 attached to a slide body 903 that operates along a horizontal operation rail 902. The elevating mechanism 910 is installed on a suspension column 911 and a suspension column 911. The rotation mechanism 912, the rotation column 914 operated by the rotation mechanism 912, and the support column 915 attached to the tip of the rotation column 914, the substrate 2 is positioned at a position connecting the end of the suspension column 911 and the end of the support column 915. Has a pedestal 916 on which is mounted. The horizontal transfer of the substrate 2 is performed by the horizontal movement of the lifting mechanism 910 and the entire mechanism suspended below the suspension column 911 by moving the slide body 903 along the horizontal operation rail 902. The substrate 2 is transferred in the vertical direction by moving the lifting mechanism 910 up and down the entire mechanism suspended below the suspension column 911. The rotation operation of the substrate 2 is performed by the rotation mechanism 912. By controlling the rotation operation, the angle of entry and exit of the substrate 2 from the melt 5 can be determined. The horizontal, vertical, and rotational operations described above can be performed independently of each other.
Next, the operation cycle of the substrate 2 by the substrate immersion mechanism 901 will be described with reference to FIG.
The substrate 2 is mounted on the pedestal 916 at the position of the substrate replacement position 606. Since the groove with the concave shape is formed on the pedestal 916 and the groove with the convex shape is formed on the substrate 2, the mounting is performed by sliding both the grooves with the groove. At this time, the surface of the substrate 2 faces the zenith direction. At that position, the substrate temperature may be adjusted using a heater or the like (not shown). Thereafter, the substrate 2 moves to the right while rotating clockwise. The position 907 is a position before immersion. Next, a thin plate is produced on the surface of the substrate 2 by immersing the surface of the substrate 2 in the melt 5 while returning to the left from the position 907 that is the pre-immersion position. In this embodiment, alignment was performed so that the center of the crucible is located at a position 908 that is an intermediate position until the substrate 2 enters the melt 5 and escapes. Note that the position 908 does not necessarily coincide with the center of the crucible. When the substrate 2 is immersed in the melt 5, a thin plate can be produced on the surface of the substrate 2 as long as it does not interfere with the crucible wall. However, the quality of the thin plate to be produced varies depending on the relationship between the immersion position and the crucible position. This is because the melt 5 has a temperature distribution in the horizontal plane, and for example, the melt temperature differs near the center of the crucible and near the wall. Therefore, it is desirable to adjust the crucible to the same position every time using the crucible moving mechanism and the alignment mechanism in the horizontal direction and using the crucible lifting mechanism in the vertical direction. As described above, the position of the crucible 6 when the substrate 2 is immersed is referred to as a substrate immersion position.
After the thin plate is manufactured, the substrate 2 on which the thin plate has been grown rotates while returning further to the left, and returns to the exchange position 906 with the surface of the substrate 2 facing the zenith direction. Thereafter, the substrate 2 on which the thin plate is formed is slid and extruded, and at the same time, a new substrate 2 is mounted.
The position of the substrate 2 when exchanging the substrate 2 is oriented in the zenith direction in the present embodiment, but may be in any direction such as sideways or downward. In FIG. 9, the operation cycle 909 is clockwise, but it may be counterclockwise, clockwise halfway, counterclockwise from the middle, or counterclockwise halfway, clockwise from the middle. In the present embodiment, for convenience of explanation, the pre-immersion position is defined as the position 907, but any position from the substrate replacement position 906 to when the substrate 2 enters the melt 5 may be used.
The above settings are usually made by programming a horizontal movement command, a lifting / lowering movement command, and a rotation operation command on a personal computer, etc., and sending them to the controller to realize an arbitrary trajectory as programmed. .
Since the silicon melt is a high temperature of 1400-1500 ° C., and there is also deposition of silicon, adhesion of SiOx powder, etc., in order to protect the substrate immersion mechanism 4, a heat insulating or cooled shielding plate (not shown) is used. It is desirable to dispose on the crucible 6 at a position that does not interfere with the substrate immersion mechanism 4 and the substrate operation.
In the case of manufacturing a silicon thin plate, the substrate 2 is preferably made of carbon from the viewpoint of heat resistance and the like. By forming irregularities at equal intervals on the surface of the substrate 2 and controlling the generation position of crystal growth nuclei, a polycrystalline thin plate having a larger crystal grain size can be produced.
The main chamber 101 only needs to be at least shut off from the outside air, but is preferably under a reduced pressure or an inert atmosphere such as helium, nitrogen, or argon.
In the present embodiment, due to solidification growth from the melt 5, the crystalline state of the thin plate is a single crystal, polycrystal, amorphous, or a mixture of crystalline and amorphous depending on conditions such as temperature. It is possible.
Furthermore, as the melt 5, it is possible to use a semiconductor material such as silicon, germanium, gallium, arsenic, indium, phosphorus, boron, antimony, zinc, tin, or a metal material such as aluminum, nickel, or iron. .
(Crucible moving mechanism)
Next, the crucible moving mechanism will be described with reference to FIG.
The melting furnace according to the present embodiment is sufficient to receive a melt even when an unexpected hot water leak occurs due to a cooling mechanism 1005 for protecting the crucible moving mechanism 1001 from heat transfer from the crucible 6, crucible cracks, or the like. Heat-resistant hot water leak receiver 1004 having a large volume, a heat insulating mechanism 1003 for suppressing heat transfer from the crucible 6 to the crucible moving mechanism 1001, the crucible 6, the crucible 6 holding the melt 5, and the melt 5 are heated and melted. The heating mechanism 7 is used for heat insulation.
The entire melting furnace is installed on the crucible moving mechanism 1001 and moves integrally with the crucible moving mechanism.
Any mechanism such as a heater and a high frequency coil may be used for the heating mechanism 7. The heating mechanism 7 includes a power introduction mechanism 1006 for performing heating.
In this embodiment, the crucible moving mechanism 1001 has a carriage 1002 and can traverse on the rail 1007 by being pushed and pulled from the outside. The crucible moving mechanism 1001 may have a mechanism for traveling on the rail 1007. What kind of mechanism is used, such as a mechanism that installs a conveyor in place of the rail 1007 and moves the conveyor by rotating, a mechanism that pushes and pulls the crucible moving mechanism on the conveyor, and a mechanism that self-runs on the conveyor It doesn't matter.
It is desirable to install an alignment mechanism 1008 that performs alignment when the crucible 6 is moved to the immersion position by the crucible moving mechanism 1001. Specifically, the alignment mechanism 1008 may use any mechanism such as a wheel stopper or positioning using an optical sensor or a touch sensor. Thereby, it becomes possible to stop the crucible 6 at the same position every time, and it can prevent that the quality of the produced thin plate differs even if a crucible movement is repeated.
In addition, it is desirable to install a mechanism 1009 for performing alignment when the crucible 6 is moved to the raw material charging position. This makes it possible to reliably place the crucible 6 in the raw material charging mechanism when the raw material is charged, and to charge the raw material without spilling the charged raw material outside the crucible 6.
Specifically, the heat insulating mechanism 1003 can be made of a ceramic block such as alumina or a heat resistant sheet having heat resistance and low thermal conductivity. In order to further reduce the thermal conductivity from the crucible 5 to the heat insulating mechanism 1003, a plurality of small blocks may be scattered so that the contact area between the heat insulating mechanism 1003 and the bottom of the crucible 6 is reduced.
For the cooling mechanism 1005, a cooling block or a cooling pipe made of metal such as copper having heat resistance and high thermal conductivity can be used. The crucible moving mechanism 1001 itself may include a cooling mechanism. As the refrigerant, a gas such as helium can be used, but a liquid such as water or oil is desirable in terms of cooling ability. A flexible tube (not shown) is connected to the cooling mechanism, and a coolant cooled by a heat exchanger (not shown) is circulated and supplied.
In addition, the crucible moving mechanism 1001 desirably has a crucible lifting / lowering mechanism 1010 that lifts and lowers the entire melting furnace in order to control the position of the melt surface where the substrate 2 and the melt 5 come into contact. As the crucible elevating mechanism 1010, for example, a screw type elevator, a cylinder type elevator or the like can be adopted.
If the crucible moves and moves up and down slowly, it is possible to prevent the melt from spilling from inside the crucible by controlling only the speed of the crucible, eliminating the need for cleaning the spilled melt and continuous operation of the equipment. Is possible. The same effect can be obtained by controlling only the movement speed change. Further, when the moving speed of the crucible is high to some extent, by controlling both the moving speed and the speed change, the melt can be prevented from spilling from the crucible and the time required for the crucible movement can be shortened. In short, it is preferable to control so as to gradually accelerate and move at high speed at the beginning and gradually decelerate at the end.
Here, in the present embodiment, by moving the crucible and the heating mechanism in the horizontal direction, when introducing the melt raw material into the crucible, it does not interfere with the substrate immersion mechanism, and the workability is improved. However, the crucible moving mechanism may move the crucible, the heating mechanism or the like in the vertical direction.
(Embodiment 1)
As shown in FIG. 1, the substrate 2 before immersion is introduced into the main chamber 101 along the arrow S <b> 1 from the sub chamber 8, mounted on the substrate immersion mechanism 4, and immersed in the melt 5. The substrate 3 immersed in the melt 5 is removed from the substrate immersion mechanism and carried out from the main chamber 101 to the sub chamber 9 along the arrow S2.
The crucible 6 and its heating mechanism 7 can move to the raw material charging position 110 in the horizontal direction along the arrow S3.
The crucible 6 can be adjusted to a desired temperature by a heating mechanism 7 disposed along the outer periphery thereof. The raw material stored in the crucible 6 is melted as the crucible 6 is heated by the heating mechanism 7 and becomes the melt 5.
Next, the manufacturing method of the thin plate in this Embodiment is demonstrated. First, the initial melting of the solid raw material is performed at the raw material charging position 110, and after the melting is completed, the crucible 6 and the heating mechanism 7 are moved in the horizontal direction to the substrate immersion position. Thereby, improvement of workability | operativity and the contamination with respect to the board | substrate immersion mechanism 4 can be reduced. Here, the contamination of the substrate immersion mechanism 4 means that, for example, when a silicon melt is used as the melt 5, SiO _x powder or the like is generated when the silicon crystalline raw material melts and adheres to the substrate immersion mechanism 4. To do. When SiO _x powder or the like adheres to the substrate immersion mechanism 4 and its periphery, troubles are likely to occur during substrate immersion.
By continuously immersing the substrate, the crucible 6 and the heating mechanism 7 are moved to the raw material charging position 110 when the amount of the melt 5 is reduced to a predetermined amount. After adding in the crucible 6 and stabilizing the temperature of the melt 5, the crucible 6 and the heating mechanism 7 using the crucible moving mechanism 1001 are moved again to the substrate immersion position, and the immersion of the substrate is resumed. Thereby, the addition of the melt raw material can be performed without interfering with the substrate immersion mechanism 4.
In the present embodiment, the raw material input mechanism 111 may have an airtight chamber structure, and a gate valve or the like may be provided between the main chamber 101 and the raw material input mechanism 111. With the gate valve closed, the additional raw material 12 is put into the raw material charging mechanism 111 from outside the apparatus, and the mixed air is discharged using a vacuum pump or the like, so that the same inert atmosphere as in the main chamber 101 is obtained. 101 can prevent outside air from being brought in. Alternatively, a configuration in which no partition such as a gate valve is provided between the main chamber 101 and the raw material charging mechanism 111 may be adopted. In this case, by setting the inside of the main chamber 101 to a pressure higher than the atmospheric pressure, air can be prevented from being mixed when the additional raw material 12 is introduced from outside the apparatus.
(Embodiment 2)
As shown in FIG. 2, a raw material charging position 210 for melting and adding an additional raw material is installed in a sub chamber 214 independent of the main chamber 201 in which the substrate is immersed. Movement of the crucible and the heating mechanism between the main chamber 201 and the sub chamber 214 is performed through the gate valve 213. Further, the melt raw material is added from the raw material charging mechanism 211 adjacent to the sub chamber 214.
By separating the main chamber 201 in which the substrate is immersed and the sub chamber 214 in which the melt raw material is melted by the gate valve 213, contamination of the substrate immersion mechanism when the raw material is melted can be eliminated. In addition, when trouble occurs in the substrate transport or substrate immersion mechanism, the crucible and the heating mechanism are moved into the sub chamber 214, so that the trouble can be recovered while the melt is held, and productivity can be improved. Loss can be reduced.
Here, in the present embodiment, by moving the crucible and the heating mechanism in the horizontal direction, the substrate immersion mechanism is not contaminated when the melt raw material is melted, and the productivity loss at the time of trouble recovery in the substrate immersion mechanism is lost. However, the sub chamber 214 may be installed below the main chamber 201 and the crucible and the heating mechanism may be moved in the vertical direction.
(Embodiment 3)
As shown in FIG. 3, two raw material input positions (310a, 310b) are installed in the sub chamber 314 partitioned by the main chamber 301 for immersing the substrate 2 and the gate valve 313 which is a partitioning mechanism. The crucibles (6a, 6b) and the heating mechanisms (7a, 7b) are provided at the respective locations. The two crucibles (6a, 6b) and the heating mechanism (7a, 7b) can be moved between the raw material charging position 310a and the main chamber 301, and between the raw material charging position 310b and the main chamber 301, respectively.
Next, a method for continuously immersing the substrate 2 using two crucibles (6a, 6b) and a heating mechanism (7a, 7b) will be described. First, the solid raw material is melted at the raw material charging position 310a and the raw material charging position 310b in the sub chamber 314. After the temperature of the melt is stabilized, the crucible 6a and the heating mechanism 7a at the raw material charging position 310a are moved to the substrate immersion position in the main chamber 301 through the gate valve 313. When the amount of the melt 5a is reduced to a predetermined amount by continuously immersing the substrate 2, the crucible 6a and the heating mechanism 7a are moved from the main chamber 301 through the gate valve 313 to the raw material in the sub chamber 314. Move to loading position 310a. Next, the crucible 6b and the heating mechanism 7b at the raw material charging position 310b are moved to the substrate immersion position in the main chamber 301 through the gate valve 313, and the immersion of the substrate 2 is resumed. While the substrate 2 is immersed, the additional raw material 12a is additionally charged from the raw material charging mechanism 311a into the crucible 6a at the raw material charging position 310a, and heated and melted to stabilize the temperature of the melt 5a. When the amount of the melt 5b in the crucible 6b in which the substrate 2 is immersed is reduced to a predetermined amount, the crucible 6b and the heating mechanism 7b are moved to the raw material charging position 310b, and the crucible 6a and the heating mechanism at the raw material charging position 310a are moved. 7a is again moved to the substrate immersion position in the main chamber 301, and the immersion of the substrate 2 is resumed. While the substrate 2 is immersed, the additional raw material 12b is additionally charged from the raw material charging mechanism 311b into the crucible 6b at the raw material charging position 310b, and heated and melted to stabilize the temperature of the melt 5b. By repeatedly performing these operations, the substrate 2 can be continuously immersed.
Thereby, the number of crucibles can be easily increased without increasing the number of sub chambers and the sub chamber atmosphere control mechanism, and the time for interrupting immersion can be shortened.
In addition, by separating the main chamber 301 in which the substrate is immersed and the sub chamber 314 in which the melt raw material is melted by the gate valve 313, contamination of the substrate immersion mechanism when the raw material is melted can be eliminated. . In addition, when trouble occurs in the substrate transport or substrate immersion mechanism, the crucible and the heating mechanism are moved into the sub chamber 314, so that the trouble can be recovered while the melt is held, and productivity is improved. Loss can be reduced.
(Embodiment 4)
As shown in FIG. 4, gate valves 413a and 413b and sub chambers 414a and 414b, which are partition mechanisms, are installed independently at two raw material charging positions 410a and 410b.
In the movement between the raw material charging positions 410a and 410b and the main chamber 401, the raw material charging position 410a is conducted through the sub chamber 414a and the gate valve 413a, and the raw material charging position 410b is moved to the sub chamber 414b and the gate valve 413b. Through. Because there is one set of sub chamber and gate valve for each crucible, it is possible to make the sub chamber atmosphere independent of the main chamber, where additional raw materials are charged, heated and melted, and temperature stabilized. Contamination to the main chamber 401 side can be eliminated when the additional raw material melted. Further, by performing the same operation as in Embodiment 3, the substrate can be continuously immersed.
By separating the main chamber 401 in which the substrate is immersed and the sub chambers 414a and 414b in which the melt raw material is melted by the gate valves 413a and 413b, contamination of the substrate immersion mechanism can be eliminated when the raw material is melted. . Also, when troubles occur in the substrate transport or substrate immersion mechanism, etc., the crucible and heating mechanism are moved into the sub chambers 414a and 414b, so that the trouble can be recovered while the melt is held, and the production Loss can be reduced.
(Embodiment 5)
As shown in FIG. 5, the raw material charging positions 510a and 510b of the two crucibles 6a and 6b and the heating mechanisms 7a and 7b and the substrate immersion position are arranged on the same axis. By adopting this arrangement, even if the two crucibles 6a and 6b move simultaneously, there is no physical interference. Therefore, the crucible 6a and the heating mechanism 7a are moved from the main chamber 501 through the gate valve 513a. The crucible 6b and the heating mechanism 7b at the raw material charging position 510b in the sub chamber 514b that holds the melt 5b at the same time as being moved to the raw material charging position 510a in the sub chamber 514a are passed through the gate valve 513b in the main chamber 501. Can be moved to. Thus, productivity can be further improved by moving the two crucibles 6a and 6b and the heating mechanisms 7a and 7b simultaneously.
Further, by separating the main chamber 501 for immersing the substrate and the sub chambers 514a and 514b for melting the melt raw material by the gate valves 513a and 513b, the substrate immersion mechanism is contaminated when the raw material is melted. It can be lost. In addition, when trouble occurs in the substrate transport or substrate immersion mechanism, the crucible and heating mechanism are moved into the sub-chambers 514a and 514b, so that the trouble can be recovered while maintaining the melt, and production Loss can be reduced.
(Tact required for thin plate production)
Here, the productivity of Embodiments 1 to 5 is compared with the productivity when the conventional apparatus shown in FIG. 8 is used (comparative example) using the tact tables shown in FIGS. 7A to 7C.
Time required for the melt to decrease to a predetermined amount: Number of sheets produced within X seconds: Time required for addition and melting of W sheets: Time required for Y seconds melt temperature stabilization: Z seconds crucible moving time: A Second gate valve opening and closing time: If B seconds, the tact (time required to create one thin plate) in each form is
Form 1: (X + Y + Z + 2A) / W
Form 2: (X + Y + Z + 2A + 2B) / W
Form 3-4: (X + 2A) / W
Form 5: (X + A) / W
Comparative example: (X + Y + Z + 2A) / W
It can be expressed. Here, since the first embodiment and the comparative example do not have a gate valve, the gate valve opening / closing time (B seconds) can be expressed as 0 in FIG. 7A.
However, in the case of Embodiments 3 to 4, it is necessary that (X + A)> (B + Y + Z). In the case of the fifth embodiment, it is necessary that (X)> (B + Y + Z).
(Embodiment 6)
As shown in FIG. 6, with respect to the main chamber 601 in which the substrate is immersed, the raw material charging positions 610a, 610b, 610c, the sub chambers 614a, 614b, 614c, the gate valves 613a, 613b, 613c, which are partition mechanisms, Three feeding mechanisms 611a, 611b, and 611c are arranged independently.
In the case of Embodiments 3 to 4, it is necessary that (X + A)> (B + Y + Z). In the case of the fifth embodiment, it is necessary that (X)> (B + Y + Z). If this relationship does not hold, that is, if the time for stabilizing the temperature of the melt after adding the raw material is longer than the time for the melt to decrease to a predetermined amount, the spare crucible and heating mechanism should be By having two or more, the substrate can be continuously immersed.
Even when the number of crucibles is two or more, tact calculation is possible based on the same concept as in the third to fourth embodiments. If the number of crucibles is N (where N> 1), the tact in the sixth embodiment is
Form 6: (X + 2A) / W
It can be expressed.
However, it is necessary that ((X + 2A) × (N−2) + (X + A)) <(B + Y + Z). It is desirable to set the number of crucibles N to a value that sufficiently satisfies the above equation.
In addition, the main chamber 601 for immersing the substrate and the sub chambers 614a, 614b, and 614c for melting the melt raw material are made independent by the gate valves 613a, 613b, and 613c, thereby melting the raw material with respect to the substrate immersion mechanism. Time pollution can be eliminated. In addition, when troubles occur in the substrate transport, substrate immersion mechanism, etc., the crucible and heating mechanism are moved into the sub chambers 614a, 614b, 614c so that the trouble can be recovered while the melt is held. , Productivity loss can be reduced.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the first embodiment. A silicon crystalline material (purity 6-Nine) having a mass of 30.0 kg was charged into a crucible 6 made of high-purity carbon having a diameter of 400 mmφ. After reducing the pressure in the apparatus to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, at the raw material charging position 110, the temperature of the crucible 6 was maintained at 1550 ° C. with an induction heating coil as the heating mechanism 7, and the silicon crystalline raw material was heated and melted to obtain a silicon melt 5. Thereafter, the melt 5 of silicon was kept at 1410 ° C. The input power when the melt 5 was held at 1410 ° C. was about 55 kW.
On the other hand, in the conventional apparatus shown in FIG. 8, in order to prevent interference between the substrate 803 attached to the movable member 802 and the raw material charging port 806, the diameter of the crucible 809 needs to be 600 mmφ. At this time, the input power when the melt 808 was held at 1410 ° C. was about 120 kW.
Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible and to reduce the input power.
Next, while holding the silicon melt 5, the crucible 6 and the induction heating coil as the heating mechanism 7 were moved to the substrate immersion position in the horizontal direction by 1800 mm at a speed of 30 mm / second. The movement of the carriage 1002 was performed by transmitting the rotational force of the drive motor attached to the carriage 1002 to the wheels of the carriage 1002 and allowing the carriage 1002 to travel on its own. A wheel stopper, which is an alignment mechanism 1008, is installed in advance so that the crucible 6 is positioned at the substrate immersion position, and the horizontal movement of the crucible by the crucible moving mechanism 1001 is stopped when the carriage 1002 contacts the wheel stopper. As the cooling mechanism 1005, a copper pipe bent several times was used, water was circulated at 30 L / min as a refrigerant, and heat exchange was performed with a chiller outside the apparatus, whereby the crucible moving mechanism 1001 was kept at substantially room temperature. . The crucible 6 is placed on an alumina block which is a heat insulation mechanism 1003.
From the sub chamber 8, a graphite substrate 2 having a size of 200 × 200 mm was introduced, and the substrate was immersed in the silicon melt 5 by the substrate immersion mechanism 4. After immersion, the substrate 3 after immersion was taken out from the sub chamber 9 to obtain a silicon thin plate.
After the substrate immersion was repeated 300 times in 50 minutes, the crucible 6 and the induction heating coil as the heating mechanism 7 were moved from the substrate immersion position to the raw material charging position 110 at a speed of 30 mm / second. The horizontal movement of the crucible by the crucible moving mechanism 1001 was stopped by the carriage 1002 coming into contact with the wheel stopper as the mechanism 1009.
10 kg of additional silicon crystalline raw material 12 is put into a raw material charging mechanism 111 having a gate valve capable of partitioning between the airtight chamber and the main room 101, and after evacuating air with a vacuum pump, argon gas Was placed in the chamber. After moving the crucible 6 to the raw material charging position 110 and opening the gate valve of the raw material charging mechanism 111, 10 kg of silicon crystalline raw material is added into the crucible 6 from the raw material charging mechanism 111, and the induction that is the heating mechanism 7 The temperature of the crucible 6 was kept at 1550 ° C. in the heating coil. It took about 30 minutes for the added raw material to completely melt. Thereafter, the set temperature of the silicon melt 5 was set to 1410 ° C. and the melt temperature was stabilized. The time required for the melt temperature stabilization was about 10 minutes.
On the other hand, in the conventional apparatus shown in FIG. 8, since the diameter of the crucible 809 needs to be 600 mmφ and the amount of the silicon melt is large, the set temperature of the silicon melt 808 is set to 1410 ° C. When waiting for stabilization, the time required for melt temperature stabilization was about 25 minutes.
Thus, by having the crucible moving mechanism, the crucible can be miniaturized and the melt temperature stabilization time can be shortened.
Thereafter, the crucible 6 and the induction heating coil as the heating mechanism 7 were moved again to the substrate immersion position, and the substrate was immersed.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + Y + Z + 2A) / W
When applying specific numerical values in this embodiment, X = 3000 seconds, W = 300 sheets, Y = 1800 seconds, Z = 600 seconds, and A = 60 seconds.
It was (3000 + 1800 + 600 + 2 × 60) /300=18.4 seconds / sheet.
Therefore, the number of sheets produced per hour in this example is about 196 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 55 kW by the number of sheets produced is about 0.28 kWh / sheet. It was.
On the other hand, in the conventional apparatus shown in FIG. 8, since it takes a long time to stabilize the melt temperature, the tact time is 21.0 seconds / sheet, and the number of sheets produced per hour is about 171 sheets / hour. The amount of power consumption per sheet obtained by dividing the input power of about 120 kW by the number of produced sheets was about 0.70 kWh / sheet.
Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.
(Comparative Example 1)
A silicon thin plate was produced using a conventional apparatus shown in FIG. A 67.5 kg mass of silicon crystalline raw material (purity 6-Nine) was charged into a crucible 809 made of high-purity carbon having a diameter of 600 mmφ. After reducing the pressure in the apparatus to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, the temperature of the crucible 809 was maintained at 1550 ° C. with the heater 804, and the silicon crystalline raw material was heated and melted to obtain a silicon melt 808. Thereafter, the silicon melt 808 was kept at 1410 ° C. The input power when the melt 808 was held at 1410 ° C. was about 120 kW, which was larger than the power of Example 1 (about 55 kW) due to the crucible size increase.
Next, while holding the silicon melt 808, the crucible 809 was raised, and the surface of the substrate 803 was immersed in the melt 808.
As the substrate 803, a graphite substrate having a size of 200 × 200 mm is continuously put into the movable member 802 from above the apparatus, and the substrate is immersed in the silicon melt 808 by the rotation of the movable member 802. The substrate was taken out upward to produce a silicon thin plate.
After immersion of the substrate was repeated 300 times in 50 minutes, the crucible 809 was lowered at a speed of 30 mm and 30 mm / second.
Through the raw material charging mechanism 806, 10 kg of silicon crystalline raw material was added to the crucible 809, and the temperature of the crucible 809 was kept at 1550 ° C. in the heater 804. It took about 30 minutes for the added raw material to completely melt. After that, when the set temperature of the silicon melt 808 was set to 1410 ° C. and the melt temperature was stabilized, it took about 25 minutes for the melt temperature to stabilize.
Thereafter, the crucible 809 and the heater 804 were moved again to the substrate immersion position, and the substrate was immersed.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + Y + Z + 2A) / W
When applying specific numerical values in the present embodiment, X = 3000 seconds, W = 300 sheets, Y = 1800 seconds, Z = 1500 seconds, and A = 1 second.
It was (3000 + 1800 + 1500 + 2 × 1) /300=21.0 seconds / sheet.
(Tact required for thin plate production)
Since the time required for melt temperature stabilization is longer in Comparative Example 1 than in Example 1, the tact is 21.0 seconds / sheet in Comparative Example 1, and the number of sheets produced per hour is about 171 sheets / hour, The amount of power consumption per thin plate obtained by dividing the input power of about 120 kW by the number of produced sheets was about 0.70 kWh / sheet. On the other hand, in Example 1, the tact was 18.4 seconds / sheet, and the power consumption per thin plate was about 0.28 kWh / sheet.
Thus, by having the crucible moving mechanism, the crucible can be miniaturized and the productivity can be improved.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the second embodiment. In the sub chamber 214, a silicon crystalline material (purity 6-Nine) having a mass of 30.0 kg was charged into a crucible 6 made of high purity carbon having a diameter of 400 mmφ. After reducing the pressure in the sub chamber 214 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, at the raw material charging position 210, the temperature of the crucible 6 was maintained at 1550 ° C. with an induction heating coil as the heating mechanism 7, and the silicon crystalline raw material was heated and melted to obtain a silicon melt 5. Thereafter, the melt 5 of silicon was kept at 1410 ° C.
Next, after reducing the pressure in the main chamber 201 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. The gate valve 213 was opened over 10 seconds, and the crucible 6 and the induction heating coil were moved 1800 mm at a speed of 30 mm / second to the substrate immersion position in the main chamber 201.
After the substrate 2 was immersed for 50 minutes and repeated 300 times, the crucible 6 and the induction heating coil as the heating mechanism 7 were moved from the substrate immersion position to the raw material charging position 210 at a speed of 30 mm / second. . Thereafter, the gate valve 213 was closed over 10 seconds, 10 kg of silicon crystalline material was added into the crucible 6 from the material charging mechanism 211, and the temperature of the crucible 6 was maintained at 1550 ° C. in the induction heating coil. It took about 30 minutes until the added raw material 12 was completely melted. Thereafter, the temperature of the silicon melt 5 was set to 1410 ° C. and held for 10 minutes.
Thereafter, the gate valve 213 was opened over 10 seconds, the crucible 6 and the induction heating coil were moved again to the substrate immersion position, and the substrate 2 was immersed.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + Y + Z + 2A + 2B) / W
When applying specific numerical values in this embodiment, X = 3000 seconds, W = 300 sheets, Y = 1800 seconds, Z = 600 seconds, A = 60 seconds, and B = 10 seconds. ,
It was (3000 + 1800 + 600 + 2 × 60 + 2 × 10) /300=18.5 seconds / sheet.
Therefore, the number of sheets produced per hour was about 195 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 120 kW by the number of sheets produced was about 0.28 kWh / sheet.
On the other hand, the tact according to Comparative Example 1 is 21.0 seconds / sheet, and the power consumption per thin plate is about 0.70 kWh / sheet. Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the third embodiment. In the sub chamber 314, a silicon crystalline raw material (purity 6-Nine) having a mass of 30.0 kg was charged into crucibles 6a and 6b made of high-purity carbon having a diameter of 400 mmφ at the raw material charging position 310a and the raw material charging position 310b. . After reducing the pressure in the sub chamber 314 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, at the raw material charging positions 310a and 310b, the temperature of the crucibles 6a and 6b is maintained at 1550 ° C. by the induction heating coils as the heating mechanisms 7a and 7b, and the silicon crystalline raw material is heated and melted to melt the silicon. Liquids 5a and 5b were obtained. Thereafter, the melts 5a and 5b of silicon were kept at 1410 ° C.
Next, after reducing the pressure inside the main chamber 301 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. The gate valve 313 is opened over 10 seconds, and first, the crucible 6a at the raw material charging position 310a and the induction heating coil as the heating mechanism 7a are moved by 1800 mm at a speed of 30 mm / second to the substrate immersion position in the main chamber 301. It was.
The immersion of the substrate 2 was continued for 50 minutes and repeated 300 times, and then the crucible 6a and the induction heating coil as the heating mechanism 7a were moved from the substrate immersion position to the raw material charging position 310a at a speed of 30 mm / second. Thereafter, the crucible 6b at the raw material charging position 310b and the induction heating coil as the heating mechanism 7b were moved to the substrate immersion position by 1800 mm at a speed of 30 mm / second, and the immersion of the substrate 2 was resumed. Meanwhile, 10 kg of silicon crystalline raw material was added from the raw material charging mechanism 311a into the crucible 6a at the raw material charging position 310a, and the temperature of the crucible 6a was maintained at 1550 ° C. in the induction heating coil as the heating mechanism 7a. It took about 30 minutes for the added raw material 12a to completely melt. Thereafter, the temperature of the silicon melt 5a was raised to 1410 ° C. and held for 10 minutes.
The immersion of the substrate 2 is further continued for 50 minutes and repeated 300 times (total 600 times), and then the induction heating coil as the crucible 6b and the heating mechanism 7b is moved from the substrate immersion position to the raw material charging position 310b at 30 mm / second. Moved at a speed of. Thereafter, the crucible 6a at the raw material charging position 310a and the induction heating coil as the heating mechanism 7a were moved to the substrate immersion position at a speed of 30 mm / second, and the immersion of the substrate 2 was resumed. While the substrate 2 is immersed, 10 kg of silicon crystalline raw material is added from the raw material charging mechanism 311b into the crucible 6b at the raw material charging position 310b, and the temperature of the crucible 6b is set to 1550 in the induction heating coil as the heating mechanism 7b. Held at 0C. Thereafter, the temperature of the silicon melt 5b was set to 1410 ° C. and held for 10 minutes.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + 2A) / W
When the specific numerical values in this embodiment are applied, X = 3000 seconds, W = 300 sheets, A = 60 seconds.
It was (3000 + 2 × 60) /300=10.4 seconds / sheet.
Accordingly, the number of sheets produced per hour was about 346 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 110 kW by the number of produced sheets was about 0.32 kWh / sheet.
On the other hand, the tact according to Comparative Example 1 is 21.0 seconds / sheet, and the power consumption per thin plate is about 0.70 kWh / sheet. Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the fourth embodiment. In the sub-chamber 414a and the sub-chamber 414b, a high-purity carbon crucible 6a having a diameter of 400 mmφ is charged with 30.0 kg of silicon crystalline raw material (purity 6-Nine) at the raw material charging position 410a and the raw material charging position 410b, respectively. , 6b was charged. After reducing the pressure in the sub chamber 414a and the sub chamber 414b to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, at the raw material charging positions 410a and 410b, the temperature of the crucibles 6a and 6b is maintained at 1550 ° C. by the induction heating coils as the heating mechanisms 7a and 7b, and the silicon crystalline raw material is heated and melted to melt the silicon. Liquids 5a and 5b were obtained. Thereafter, the melts 5a and 5b of silicon were kept at 1410 ° C.
Next, after reducing the pressure in the main chamber 401 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. The gate valve 413a is opened over 5 seconds. First, the crucible 6a at the raw material charging position 410a and the induction heating coil as the heating mechanism 7a are moved by 1800 mm at a speed of 30 mm / second to the substrate immersion position in the main chamber 401. It was.
The immersion of the substrate 2 was continued for 50 minutes and repeated 300 times, and then the crucible 6a and the induction heating coil as the heating mechanism 7a were moved from the substrate immersion position to the raw material charging position 410a at a speed of 30 mm / second. Thereafter, the gate valve 413a was closed over 5 seconds and simultaneously the gate valve 413b was opened over 5 seconds. The crucible 6b at the raw material charging position 410b and the induction heating coil as the heating mechanism 7b were moved to the substrate immersion position by 1800 mm at a speed of 30 mm / second, and the immersion of the substrate 2 was resumed. Meanwhile, 10 kg of silicon crystalline raw material was added from the raw material charging mechanism 411a into the crucible 6a at the raw material charging position 410a, and the temperature of the crucible 6a was maintained at 1550 ° C. in the induction heating coil as the heating mechanism 7a. It took about 30 minutes for the added raw material 12a to completely melt. Thereafter, the temperature of the silicon melt 5a was raised to 1410 ° C. and held for 10 minutes.
The immersion of the substrate 2 is continued for another 50 minutes and repeated 300 times (600 times in total), and then the induction heating coil as the crucible 6b and the heating mechanism 7b is moved from the substrate immersion position to the raw material charging position 410b at 30 mm / second. Moved at speed. Thereafter, the gate valve 413b is closed over 5 seconds, and at the same time, the gate valve 413a is opened, and the crucible 6a at the raw material charging position 410a and the induction heating coil as the heating mechanism 7a are moved to the substrate immersion position at a speed of 30 mm / second. The immersion of the substrate 2 was resumed. While the substrate 2 is immersed, 10 kg of silicon crystalline raw material is added from the raw material charging mechanism 411b into the crucible 6b at the raw material charging position 410b, and the temperature of the crucible 6b is set to 1550 in the induction heating coil as the heating mechanism 7b. Held at 0C. Thereafter, the temperature of the silicon melt 5b was set to 1410 ° C. and held for 10 minutes.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + 2A) / W
When the specific numerical values in this embodiment are applied, X = 3000 seconds, W = 300 sheets, A = 60 seconds.
It was (3000 + 2 × 60) /300=10.4 seconds / sheet.
Accordingly, the number of sheets produced per hour was about 346 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 110 kW by the number of produced sheets was about 0.32 kWh / sheet.
On the other hand, the tact according to Comparative Example 1 is 21.0 seconds / sheet, and the power consumption per thin plate is about 0.70 kWh / sheet. Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the fifth embodiment. In the sub-chamber 514a and the sub-chamber 514b, a high-purity carbon crucible 6a having a diameter of 400 mmφ is charged with 30.0 kg of silicon crystalline raw material (purity 6-Nine) at the raw material charging position 510a and the raw material charging position 510b, respectively. , 6b was charged. After reducing the pressure in the sub chamber 514a and the sub chamber 514b to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. Subsequently, at the raw material charging positions 510a and 510b, the temperature of the crucibles 6a and 6b is maintained at 1550 ° C. with the induction heating coils as the heating mechanisms 7a and 7b, and the silicon crystalline raw material is heated and melted to melt the silicon. Liquids 5a and 5b were obtained. Thereafter, the melts 5a and 5b of silicon were kept at 1410 ° C.
Next, after reducing the pressure in the main chamber 501 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. The gate valve 513a is opened over 5 seconds. First, the crucible 6a at the raw material charging position 510a and the induction heating coil as the heating mechanism 7a are moved by 1800 mm at a speed of 30 mm / second to the substrate immersion position in the main chamber 501. It was.
After the substrate 2 is immersed for 50 minutes and repeated 300 times, the gate valve 513b is opened over 5 seconds, and the crucible 6a at the substrate immersion position and the induction heating coil as the heating mechanism 7a are moved to the raw material charging position 510a. At the same time, the crucible 6b at the raw material charging position 510b and the induction heating coil as the heating mechanism 7b are moved to the substrate immersion position by 1800mm at a speed of 30mm / second, and the immersion is resumed. did. After the crucible 6a and the induction heating coil as the heating mechanism 7a are moved to the raw material charging position 510a, the gate valve 513a is closed over 5 seconds, and the silicon crystalline material is put into the crucible 6a at the raw material charging position 510a from the raw material charging position 511a. 10 kg of raw material was added, and the temperature of the crucible 6a was kept at 1550 ° C. in the induction heating coil which is the heating mechanism 7a. It took about 30 minutes for the added raw material 12a to completely melt. Thereafter, the temperature of the silicon melt 5a was raised to 1410 ° C. and held for 10 minutes.
The substrate 2 is further immersed for 50 minutes and repeated 300 times (total 600 times). Then, the gate valve 513a is opened, and the crucible 6b at the substrate immersion position and the induction heating coil as the heating mechanism 7b are connected to the raw material charging position 510b. At the same time, the crucible 6a at the raw material charging position 510a and the induction heating coil as the heating mechanism 7a were moved to the substrate immersion position at a speed of 30 mm / second to resume immersion. . After moving the crucible 6b and the induction heating coil as the heating mechanism 7b to the raw material charging position 510b, the gate valve 513b is closed over 5 seconds, and the silicon crystalline material is put into the crucible 6b at the raw material charging position 510b by the raw material charging mechanism 511b. 10 kg of raw material was added, and the temperature of the crucible 6b was kept at 1550 ° C. in the induction heating coil which is the heating mechanism 7b. Thereafter, the temperature of the silicon melt 5b was set to 1410 ° C. and held for 10 minutes.
When the tact in this example is expressed by the mathematical formula shown in the fifth embodiment,
(X + A) / W
When the specific numerical values in this embodiment are applied, X = 3000 seconds, W = 300 sheets, A = 60 seconds.
It was (3000 + 60) /300=10.2 seconds / sheet.
Therefore, the number of sheets produced per hour was about 353 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 110 kW by the number of sheets produced was about 0.31 kWh / sheet.
On the other hand, the tact according to Comparative Example 1 is 21.0 seconds / sheet, and the power consumption per thin plate is about 0.70 kWh / sheet. Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.

A silicon thin plate was manufactured using the thin plate manufacturing apparatus described in the sixth embodiment. In the sub chamber 614a, the sub chamber 614b, and the sub chamber 614c, a silicon crystalline material having a mass of 30.0 kg (purity 6-Nine) has a diameter at the raw material charging position 610a, the raw material charging position 610b, and the raw material charging position 610c, respectively. The crucibles 6a, 6b and 6c made of high purity carbon of 400 mmφ were charged. The sub chambers 614a, 614b, and 614c were depressurized to 7.0 × 10 ⁻³ Pa, and then argon gas was introduced to normal pressure. Subsequently, at the raw material charging positions 610a, 610b, and 610c, the temperature of the crucibles 6a, 6b, and 6c is maintained at 1550 ° C. by the induction heating coils that are the heating mechanisms 7a, 7b, and 7c, and the silicon crystalline raw material is heated to be melted. Thus, silicon melts 5a, 5b and 5c were obtained. Thereafter, the silicon melts 5a, 5b and 5c were kept at 1410 ° C.
Next, after reducing the pressure in the main chamber 601 to 7.0 × 10 ⁻³ Pa, argon gas was introduced to normal pressure. The gate valve 613a is opened for 5 seconds, and first, the crucible 6a at the raw material charging position 610a and the induction heating coil as the heating mechanism 7a are moved by 1800 mm at a speed of 30 mm / second to the substrate immersion position in the main chamber 601. It was.
After the substrate 2 was immersed for 25 minutes and repeated 150 times, the induction heating coil as the crucible 6a and the heating mechanism 7a were moved from the substrate immersion position to the raw material charging position 610a at a speed of 30 mm / second. . Thereafter, the gate valve 613a was closed over 5 seconds and simultaneously the gate valve 613b was opened over 5 seconds. The crucible 6b at the raw material charging position 610b and the induction heating coil as the heating mechanism 7b were moved to the substrate immersion position by 1800 mm at a speed of 30 mm / second, and the immersion of the substrate 2 was resumed. Meanwhile, 5 kg of silicon crystalline raw material was added from the raw material charging mechanism 611a into the crucible 6a at the raw material charging position 610a, and the temperature of the crucible 6a was maintained at 1550 ° C. in the induction heating coil as the heating mechanism 7a. It took about 20 minutes for the added raw material 12a to completely melt. Thereafter, the temperature of the silicon melt 5a was raised to 1410 ° C. and held for 10 minutes.
The immersion of the substrate 2 was continued for another 25 minutes and repeated 150 times (total 300 times), and then the induction heating coil as the crucible 6b and the heating mechanism 7b was moved from the substrate immersion position to the raw material charging position 610b at 30 mm / second. Moved at a speed of. Then, simultaneously with closing the gate valve 613b over 5 seconds, the gate valve 613c is opened over 5 seconds, and the crucible 6c at the raw material charging position 610c and the induction heating coil as the heating mechanism 7c are moved to the substrate immersion position at 30 mm / second. The substrate 2 was moved at a speed of 1800 mm, and the immersion of the substrate 2 was resumed. While the substrate 2 is immersed, 5 kg of silicon crystalline raw material is added from the raw material charging mechanism 611b to the crucible 6b at the raw material charging position 610b, and the temperature of the crucible 6b is set to 1550 in the induction heating coil as the heating mechanism 7b. Held at 0C. Thereafter, the temperature of the silicon melt 5b was set to 1410 ° C. and held for 10 minutes.
The immersion of the substrate 2 was continued for another 25 minutes and repeated 150 times (total 450 times), and then the induction heating coil as the crucible 6c and the heating mechanism 7c was moved from the substrate immersion position to the raw material charging position 610c at 30 mm / second. Moved at a speed of. Thereafter, the gate valve 613c is closed over 5 seconds, and at the same time, the gate valve 613a is opened, and the crucible 6a at the raw material charging position 610a and the induction heating coil as the heating mechanism 7a are moved to the substrate immersion position at a speed of 30 mm / second. The immersion of the substrate 2 was resumed. While the substrate 2 is immersed, 5 kg of silicon crystalline raw material is added from the raw material charging mechanism 611c into the crucible 6c at the raw material charging position 610c, and the temperature of the crucible 6c is set to 1550 in the induction heating coil as the heating mechanism 7c. Held at 0C. Thereafter, the temperature of the silicon melt 5c was raised to 1410 ° C. and held for 10 minutes.
When the tact in this example is expressed by the mathematical formula shown in the sixth embodiment,
(X + 2A) / W
When applying specific numerical values in this embodiment, X = 1500 seconds, W = 150 sheets, A = 60 seconds.
It was (1500 + 2 × 60) /150=10.8 seconds / sheet.
Therefore, the number of sheets produced per hour was about 333 sheets / hour, and the power consumption per sheet obtained by dividing the input power of about 165 kW by the number of sheets produced was about 0.50 kWh / sheet.
On the other hand, the tact according to Comparative Example 1 is 21.0 seconds / sheet, and the power consumption per thin plate is about 0.70 kWh / sheet. Thus, by having the crucible moving mechanism, it is possible to reduce the size of the crucible, and it is possible to improve productivity by shortening the tact and reducing the power consumption per thin plate.

According to the thin plate manufacturing apparatus of the present invention, the melting of the melt raw material and the crucible holding the obtained melt can be moved, and a sub chamber independent from the main chamber having the substrate immersion mechanism is installed, By melting the melt raw material and holding the melt in the room, workability can be improved when the raw material is additionally charged into the crucible.
Furthermore, by using two or more crucibles and using one for immersing the substrate while the rest is used for adding and melting the melt raw material, it is possible to continuously produce thin plates by alternating exchange. Thus, productivity can be greatly improved.

Claims (23)

In the thin plate manufacturing apparatus for forming a thin plate on the surface of the substrate by immersing the substrate (2) in the melt (5) in the crucible (6), the thin plate manufacturing apparatus has a moving mechanism for the crucible. The thin plate manufacturing apparatus according to claim 1, further comprising a raw material charging mechanism (111) for charging an additional raw material into the crucible. The thin plate manufacturing apparatus according to claim 1, wherein the crucible moving mechanism has an alignment mechanism (1008) for aligning the crucible at a place where the substrate is immersed in the melt. The thin plate manufacturing apparatus according to claim 1, further comprising a mechanism for controlling a moving speed and / or a change in speed of the crucible so that the melt does not spill during the movement of the crucible. The thin plate manufacturing apparatus according to claim 1, further comprising a heat insulating mechanism (1003) between the crucible moving mechanism and the crucible. The thin plate manufacturing apparatus according to claim 1, further comprising a cooling mechanism (1005) between the crucible moving mechanism and the crucible. The thin plate manufacturing apparatus according to claim 1, wherein the raw material charging mechanism is installed at a position different from the substrate immersion mechanism (4) for immersing the substrate in the melt. The crucible forms the thin plate when the substrate dipping mechanism is located at a dipping position where the substrate is dipped into the melt, and the crucible is located at a location different from the dipping position when the additional raw material is used. 2. The thin plate manufacturing apparatus according to claim 1, wherein the crucible is put into a crucible. The said additional raw material is injected | thrown-in to the said crucible in the subchamber (9) which can hold | maintain the atmosphere independent of the main chamber (101) which has the said substrate immersion mechanism. Thin plate manufacturing equipment. The thin plate manufacturing apparatus according to claim 9, wherein the sub chamber includes the raw material charging mechanism. The raw material charging mechanism includes a raw material charging chamber, a replacement mechanism for making the atmosphere in the raw material charging chamber the same as the atmosphere in the sub chamber, and a partition mechanism for partitioning the raw material charging chamber and the sub chamber. The thin plate manufacturing apparatus according to claim 9, comprising: The thin plate manufacturing apparatus according to claim 1, comprising at least two crucibles. The thin plate manufacturing apparatus according to claim 12, wherein a plurality of the crucibles can be juxtaposed in one sub chamber. 13. The thin plate manufacturing apparatus according to claim 12, wherein the number of the crucible moving mechanisms is the same as the number of the crucibles. The thin plate manufacturing apparatus according to claim 14, wherein the number of the raw material charging mechanisms is the same as that of the crucibles. The apparatus for manufacturing a thin plate according to claim 15, wherein the number of the sub chambers is the same as the number of the crucibles. In the thin plate manufacturing method of forming a thin plate on the surface of the substrate by immersing the substrate held in the substrate immersion mechanism in the melt in the crucible,
A method for producing a thin plate, wherein the solid raw material in the crucible is heated and melted at a position different from the immersion position. The thin plate manufacturing method according to claim 17, wherein the heating and melting place is a sub chamber capable of maintaining an atmosphere independent of the main chamber. The thin plate manufacturing method according to claim 17, further comprising a step of adding an additional raw material to the crucible. Producing the thin plate at the immersion position;
Moving the crucible to a raw material charging position (110);
Charging the additional raw material into the crucible;
Moving the crucible to a dipping position;
The thin plate manufacturing method according to claim 17, comprising: Producing the thin plate using one crucible at the immersion position;
Moving the one crucible to one raw material charging position;
Charging the additional raw material into the one crucible;
Moving the one crucible to the immersion position;
Producing the thin plate using another crucible different from the one crucible at the immersion position;
Moving the other one crucible to another one raw material charging position different from the one raw material charging position;
Charging the additional raw material into the other crucible;
Moving the other one crucible to the immersion position;
The thin plate manufacturing method according to claim 17, comprising: When performing the step of producing the thin plate using the one crucible,
Charging the additional raw material into the other crucible;
Heating and dissolving the additional raw material charged into the other crucible;
Stabilizing the temperature of the melt held in the other one crucible;
The method for producing a thin plate according to claim 21, wherein at least one of the following steps is performed. When performing the step of moving the one crucible to the immersion position,
The thin plate manufacturing method according to claim 21, wherein the step of moving another crucible different from the one crucible to another raw material charging position different from the one raw material charging position is performed.

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