JP2014523488A - Cartridge reactor for material production by chemical vapor deposition - Google Patents

Abstract

  The present invention overcomes the limitations of the Siemens reactor by allowing the precipitation reaction to take place inside a sealed crucible rather than the entire cavity inside the water-cooled reactor. The crucible itself is placed inside the cartridge reactor, which has a heat shield between the crucible and the reactor wall, which can significantly reduce radiant energy loss. Furthermore, the ratio of the deposition surface area to the cavity volume in the crucible is much larger than the ratio of the deposition surface area of the rod to the total cavity volume in the Siemens reactor, resulting in a much higher proportion of gas molecules in contact with the deposition surface. Get higher. As a result, a much higher effective conversion rate from the substance in the gas to the substance on the deposition surface can be obtained.

Description

  The present invention relates to a method and a reactor for producing a substance by chemical vapor deposition.

No. 12 / 597,151 filed Oct. 22, 2009 (“'151 patent application”) “Deposition of high-purity silicon via high-surface-area gas-solid or gas-liquid”. "interfaces and recovery via liquid phase" is incorporated by reference in its entirety. This application is a co-application title entitled “DEPOSITION CARTRIDGE FOR PRODUCTION OF MATERIALS VIA THE CHEMICAL VAPOR DEPOSITION PROCESS” filed at the same time as this application. Are added when notified), which is also incorporated by reference in its entirety. This application is further related to US Provisional Application No. 6154148 (“'148 Patent Provisional Application”) filed July 1, 2011, “Deposition cartridge for production of high quality and christian year 11 and 20th year”. U.S. Provisional Application No. 61504145 filed on Jan. 1 ("'145 Patent Provisional Application") "Cartridge Reactor for Production of High-Purity Amorphous and Crystalline Silicon and Other" All of which are incorporated herein. In the '151 patent application, the term “deposition plate” is defined as the surface on which silicon is deposited, but for clarity in describing the actual physical components in this patent application, “ The “deposition surface” is defined as the surface on which the material is deposited, and the “deposition plate” is the actual physical layer on which the material is deposited, preferably on both sides and on one or more edges. It is defined as a flat plate (an object having a fairly large surface area on both sides compared to its edges). Therefore, both surfaces and edges of the deposition plate are the deposition surfaces. The term “deposition cartridge” is defined as a combination of a distribution rod and a single plate deposition plate, or a single serpentine pattern deposition plate, either of which can incorporate an insulating layer or spacer. The term “Siemens reactor” is defined as a deposition reactor that is originally designed to use a seed rod.

The '151 patent application describes the limitations of the Siemens reactor, including: That is,
1. The low average surface area of the polycrystalline silicon rod, which results in a low volume deposition rate, ie low Siemens reactor productivity (the amount of polycrystalline silicon produced during a given period, usually meters per year Measured by tons),
2. The low surface area to volume ratio of the polycrystalline silicon rod, which results in a significant energy consumption to maintain the surface temperature necessary to achieve precipitation over the long time required to achieve a significant amount of precipitation become,
3. This is a characteristic that requires a lot of labor in the rod collecting process and is easily mixed with impurities.

The invention described in the '151 patent application overcomes these limitations by using large surface area electrically heated deposition plates. Silicon is deposited at a high volumetric rate on these plates by a CVD process and then recovered by further heating the plates. By further heating, a very thin layer of polycrystalline silicon deposited at the interface of the plate is melted and the solid crust of deposited polycrystalline silicon can be peeled off the plate mechanically or by gravity. Using a large plate in a Siemens reactor increases the productivity of the reactor compared to the use of a traditional seed rod, while using a small plate produces the same production as using a seed rod The energy consumption of the reactor is reduced while maintaining the characteristics. However, further limitations of the Siemens reactor remain, including but not limited to: That is,
1. High radiant energy loss from the rod to the reactor wall, which must be cooled to prevent the deposition of polycrystalline silicon on the reactor wall in addition to the rod,
2. Since the ratio of the deposition surface area to the total cavity volume of the reactor is low, the ratio of the deposition gas molecules contacting the deposition surface area is low. The low effective conversion rate of silicon in the gas to silicon on the rod is the result of a low rate of contact, although the event is governed by reaction equilibrium.

  The present invention overcomes the limitations of the Siemens reactor described above by allowing the precipitation reaction to take place inside a sealed crucible rather than the entire cavity inside the water-cooled reactor. Precipitation on the inner wall of the reactor is undesirable because it leads to loss of material produced, but deposition on the inner wall of the crucible is practically desirable because it increases the deposition rate by increasing the deposition surface area. The crucible itself is placed inside the cartridge reactor, which has a heat shield between the crucible and the reactor wall, which can significantly reduce radiant energy loss. Normally, up to 60-70% of the energy used by the Siemens reactors is deprived by the unshielded water-cooled walls of the reactors.

  Furthermore, the ratio of the deposition surface area to the cavity volume in the crucible is much larger than the ratio of the deposition surface area of the rod to the total cavity volume in the Siemens reactor, resulting in a much higher proportion of gas molecules in contact with the deposition surface. Get higher. As a result, a much higher effective conversion rate from the substance in the gas to the substance on the deposition surface can be obtained.

FIG. 2 is an elevational cross-sectional view of one preferred embodiment of the main components of the cartridge reactor. 1 is a cross-sectional plan view of a preferred embodiment of the main components of a cartridge reactor. 1 is a perspective view of a preferred embodiment of a deposition cartridge for a cartridge reactor. FIG. 1 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor with the bottom assembly lowered and the crucible mounted. FIG. 1 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor with the bottom assembly raised and the reactor pressurized with an inert gas. FIG. 1 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor with the crucible raised and the deposition cartridge pre-heated. FIG. 2 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor during a deposition sequence. FIG. 1 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor during directional solidification with an inert gas present in the reactor. FIG. 1 is an elevational cross-sectional view of a preferred embodiment of a cartridge reactor during cooling and air purging. FIG. FIG. 2 is an elevational cross-sectional view of a preferred embodiment of the cartridge reactor with the bottom assembly lowered and the crucible removed. FIG. 2 is a side elevational cross-sectional view of a preferred embodiment of a reactor upper assembly. FIG. 6 is a front elevational cross-sectional view of a preferred embodiment of a reactor upper assembly. FIG. 2 is a cross-sectional plan view (bottom view) of a preferred embodiment of the reactor upper assembly. 1 is a side elevational cross-sectional view of a preferred embodiment of a crucible during deposition showing a gas flow pattern. FIG. 1 is a cross-sectional plan view of a preferred embodiment of a crucible after deposition showing a crust of material. FIG.

  The main components of one preferred embodiment of a cartridge reactor 50 that produces material by CVD is shown in FIG. In this embodiment, the reactor upper assembly 1 is described in the deposition cartridge 2 (the cartridge is described in the '148 and' 145 patent applications, and the “DEPOSITION CARTRIDGE FOR PRODUCTION OF MATERIALS VIA THE CHEMICAL VAPOR DEPOSITION PROCESS” filed concurrently with this application. And the deposition gas mixture is spread over the deposition surface of the deposition cartridge 2, the exhaust gas is removed, and heat exchange is performed between the exhaust gas and the deposition gas mixture. The array of deposition cartridges 2 preferably has a square cross section if the desired final product is a single crystal material and a circular cross section if the desired final product is a single crystal material. The reactor upper assembly 1 is attached to the reactor intermediate assembly 3 by a reactor flange 9 incorporating an airtight seal. The reactor intermediate assembly 3 contains a crystallization heating device 4. A reactor bottom assembly 6 that can be raised to and lowered from the reactor intermediate assembly 3 is a vertically movable crucible base equipped with a bottom cooling device 10 for cooling the crucible during directional solidification. 5 is accommodated. All assemblies in the reactor incorporate a heat shield to minimize radiant energy loss.

  As shown in FIG. 2, the reactor wall 35 of the reactor top assembly 1, the reactor intermediate assembly 3, and the reactor bottom assembly 6 is preferably circular in cross section and preferably further water cooled. The planar cross-sections of the heat shield 13, the array of precipitation cartridges 2, the crystallization heating device 4, and the bottom cooling device 10 are preferably square if a polycrystalline material is desired, and a single crystal material is desired. For example, it is preferably circular.

  FIG. 3 is a perspective view of a preferred embodiment of an array of deposition cartridges 2 attached to the reactor upper assembly. The deposition cartridge 2 is connected to the distribution bar 32 by an electrode bracket 57 through the electrode tabs 53. There are 16 deposition cartridges 2, which are spaced about 5 cm apart, are about 42 cm high and about 75 cm long. Assuming a deposition crust of about 2 cm thick on the inner wall of the deposition cartridge 2 and the crucible, the array of deposition cartridges 2 of this preferred embodiment is typically used for crystallization of deposited materials including, but not limited to, polycrystalline silicon. Is designed to fit inside the 85cm x 85cm crucible.

This preferred embodiment of the cartridge reactor 50 operates in the following seven preferred stages.
1. The crucible mounting stage is shown in FIG. Preferably, the reactor bottom assembly 6 is lowered and the crucible 11, preferably made of quartz, is accurately placed on the crucible base 5.
2. The inert gas purge stage is shown in FIG. Preferably, the reactor bottom assembly 6 is raised to seal between the reactor bottom assembly and the airtight reactor flange 6 of the reactor intermediate assembly 3. The reactor cavity is purged with an inert gas, preferably nitrogen, using the reactor gas inlet 18 and the gas inlet and outlet of the reactor upper assembly 1. Preferably, the cartridge reactor 50 is further increased to operating pressure (preferably within 6 bar).
3. The preheating stage is shown in FIG. Preferably, the crucible base 5 is raised so that the upper edge of the crucible 11 presses the gas seal 19 to form an airtight seal. Preferably, the deposition cartridge 2 is then electrically preheated to the optimum deposition temperature, which is preferably in the range of 850 ° C. to 1,150 ° C. when the deposited material is polycrystalline silicon. The heat shield 13 of the cartridge reactor 50 minimizes radiant energy loss and minimizes the cooling work of the water cooled reactor wall 35.
4). The deposition sequence stage is shown in FIG. Preferably, when the deposited material is polycrystalline silicon, a deposition gas mixture, preferably trichlorosilane and hydrogen, or monosilane is pumped from the gas inlet of the reactor upper assembly 1 to the crucible 11 and at the same time an inert gas, preferably Nitrogen is maintained in the remainder of the cavity outside the crucible. Preferably, for safety, the inert gas is such that if the gas seal 19 leaks, the combustible deposition gas mixture does not leak from the crucible 11 but the inert gas leaks into the crucible 11. The pressure is slightly higher than the deposition gas. Alternatively, in this preferred embodiment, if there is a leak in the reactor flange 9, the combustible deposition gas mixture does not leak from the cartridge reactor 50, but inert gas leaks from the cartridge reactor 50, which Yet another safety improvement over the Siemens reactor. The gas seal 19 is preferably selected to withstand relatively high temperatures, in which there are preferred sealing materials, such as carbon-based materials, while the gas seal preferably has a relatively small differential pressure. receive. Preferably, the precipitation gas mixture pumped into the crucible 11 contacts the heated precipitation surface of the precipitation cartridge 2, undergoes a precipitation reaction, is converted to exhaust gas, and is removed through the gas outlet of the reactor upper assembly 1. . In this preferred embodiment, this process continues until the material crust 14 is deposited on the deposition surface, so that the space inside the crucible 11 is almost full. When this is almost full, both the inside and outside of the crucible 11 are purged with a suitable inert gas, preferably argon, and preferably both the inside and outside of the crucible 11 are evacuated. Next, the deposition surface is further heated to the melting point of the substance or higher, and the thin layer of the substance is liquefied on the precipitation surface of the precipitation cartridge 2, and the substance crust is peeled off from the precipitation cartridge 2.
5. The crystallization stage is shown in FIG. Preferably, the crucible table 5 carrying the crucible 11 and the substance crust 14 is lowered into the reactor intermediate assembly 3, and the substance crust 14 is further heated by the crystallization heating device 4 until it becomes a liquid substance 15. Preferably, the heat shield 13 incorporates a reflective layer that minimizes radiant energy loss and an insulating layer that minimizes conduction and convective energy loss can be incorporated outside the reflective layer. In this preferred embodiment, the directional solidification includes one or more including the operation of the bottom cooling device 10, the control of the crystallization heating device 4, and / or the movement of the crucible table 5 away from the crystallization heating device 4. It is achieved by more than that means. During this crystallization stage, the rotating heat shield 12 is closed to insulate over the top of the crucible 11 to minimize energy loss. The solidification front 16 moves upward in the liquid material 15 and forms a crystalline material ingot 17 behind it. In another preferred embodiment of the above crystallization stage, the substance crust 14 can be completely melted by the precipitation cartridge 2 while the crucible 11 remains in the fully raised position. Next, the crucible 11 is lowered while being controlled, and during this time, the deposition cartridge 2 can continue to heat the liquid silicon, and the bottom cooling device 10 can be operated to start directional solidification. This preferred embodiment has the potential to produce higher quality crystalline silicon by allowing the crystallization process to be accelerated while keeping the solidification front 16 more flat. Both of the preferred embodiments described above will produce polycrystalline material, and a square flat cross-sectional shape is preferred for the array of precipitation cartridges 2, the crucible 11, and the bottom cooling device 10. On the other hand, in another preferred embodiment, this flat cross-sectional shape is circular and a single crystal ingot is produced by the Czochralski crystallization process by introducing a rotary draw rod from the reactor upper assembly 1 into the liquid material 15. You can also. Finally, in another preferred embodiment, this entire crystallization step can be omitted, using the cartridge reactor 50 to produce only amorphous material in the crucible and further processing elsewhere. Can do.
6). A cooling and air purge stage is shown in FIG. 9, in which the vacuum is replaced by a circulating inert gas, preferably argon, for convective cooling. After sufficient cooling of the crucible for ease of subsequent handling, the inert gas is purged with air in preparation for releasing and lowering the reactor bottom assembly 6 seal. In a preferred embodiment where the crystallization step is omitted, cooling of the crucible 11 and material crust 14 can be omitted so that energy consumption in subsequent processing steps can be minimized as appropriate.
7). The crucible unloading stage is shown in FIG. Preferably, the reactor bottom assembly is unsealed and lowered, and the crucible 11 containing the crystalline material ingot 17 is unloaded.

  One feature of the preferred embodiment of the cartridge reactor 50 is the effective distribution and preheating of the deposition gas mixture achieved in the reactor upper assembly 1. In FIG. 11, which is a side elevational cross-sectional view of the reactor upper assembly 1, the deposition gas mixture enters the deposition gas mixture inlet manifold 29 through the deposition gas mixture inlet 20. In this preferred embodiment, the deposition gas mixture is directed into a number of deposition gas mixture inlet nozzles 24 that extend downward and open directly above the deposition cartridge 2 at the bottom position of the reactor upper assembly 1. . The deposition gas mixture is injected through each deposition gas mixture nozzle 24, flows downward between the deposition cartridges 2, and hits the bottom of the crucible 11. The blocking effect between adjacent flows of the deposition gas mixture that strikes the bottom of the crucible 11 minimizes the lateral spread of the deposition gas mixture, and the deposition gas mixture preferably flows downwardly from the deposition gas mixture nozzle 24. The deposition gas mixture and the deposition cartridge 2 are flowed back upward, preferably in a vortex or turbulent motion (see also FIGS. 12, 13 and in particular 14). This turbulent flow preferably brings the deposition gas mixture into more complete contact with the deposition cartridge 2, thereby more fully converting the material in the deposition gas mixture to the material on the deposition surface.

  In this preferred embodiment, the exhaust gas continues to flow upward through the exhaust gas outlet annulus 25 surrounding the deposition gas mixture inlet nozzle 24, where it is removed. This heated exhaust gas flowing upwardly through the exhaust gas outlet annulus 25 heats the precipitated gas mixture flowing downwardly through the precipitation gas mixture nozzle 24. The exhaust gas also heats the cooling water that flows outside the exhaust gas outlet annulus in the exhaust gas aftercooler 26. Another preferred embodiment of the deposition gas mixture distribution pattern includes individual alternating inlet and outlet nozzles or rows of alternating inlet and outlet nozzles.

  The exhaust gas is collected in a single stream from the multiple exhaust gas outlet annulus 25 within the exhaust gas outlet manifold 27 and exits the reactor upper assembly through the exhaust gas outlet 22. On the other hand, the cooling water heated in the exhaust gas aftercooler 26 flows to the precipitation gas mixture preheating device 28, where initial heating is performed on the precipitation gas mixture that has just entered from the precipitation gas mixture inlet nozzle 24. I do. This cooling water then leaves the reactor upper assembly 1 through the cooling water outlet 21.

  FIGS. 11 and 13 show a preferred embodiment of the reactor upper assembly 1 with the deposition gas mixture inlet nozzle 24 positioned just above the gap between the deposition cartridges 2 attached to the distribution bar 32. FIGS. 11 and 13 also show the deposition cartridge 2 electrically connected in parallel via a distribution bar 32, which itself forms an electrically insulating hermetic seal against the side wall of the exhaust gas aftercooler 26. It is connected to the power supply via the distribution bar electrode 31. In another preferred embodiment, the electrode tab 53 or the electrode bracket 57 can be passed through an insulated steel tube and extended upwards and out through the head of the reactor upper assembly 1. It can be connected to the power supply at the top contact.

  A preferred embodiment of the crucible 11 after deposition and separation from the deposition cartridge 2 is shown in FIG. The material deposited on the inner wall of the crucible 11 and the deposition surface of the deposition cartridge 2 fills most of the crucible volume, leaving a thin deposition cartridge cavity 36 instead of the deposition cartridge 2.

The preferred advantages of this cartridge reactor over the Siemens reactor are as follows.
1. Faster volumetric deposition rate due to the larger surface area for deposition.
2. As a result of the higher ratio of the deposition surface area to the deposition gas mixture inclusion volume, and the more complete contact of the deposition gas mixture with the deposition surface, made possible by the combination of the deposition cartridge geometry and the gas inlet nozzle geometry. Higher effective conversion rate of substances in the precipitation gas mixture to substances on the precipitation surface.
3. Energy savings by minimizing radiant heat loss from the deposition cartridge geometry. Most of the radiant heat emitted from the heated deposition surface is absorbed by the adjacent deposition surface.
4). Energy savings by minimizing radiation, conduction, and convective heat loss to the water-cooled reactor wall. Since the deposition takes place inside a sealed crucible, the reactor wall outside the crucible can be shielded by a heat shield.
5. Energy savings by melting the material for crystallization from the precipitation temperature rather than from the ambient temperature. Whether the crystallization takes place in a cartridge reactor or in a separate crystallizer, the material is already in the crucible and does not need to be handled directly and therefore needs to be cooled to ambient temperature There is no.
6). Eliminate material contamination by handling, and eliminate processes for repairing contamination by handling, such as acid etching.
7). Eliminate the process of crushing materials into easily sized chunks for filling in crucibles.
8). Faster and higher quality crystallization by pulling the deposition cartridge out of the molten silicon under control.
9. Reduced production facilities by converting the deposition gas mixture more completely into exhaust gas, resulting in less exhaust gas processing downstream of the cartridge reactor.
10. Simplified electrical system consisting of a single electrode pair connecting the deposition cartridges in parallel or in series compared to individual electrode pairs for each rod pair in a Siemens reactor.
11. Improved safety by containing the combustible deposition gas mixture in an additional wall of the crucible and maintaining the inert gas in the reactor cavity at a slightly higher pressure than the deposition gas mixture in the crucible.
12 Design that can be easily resized. To provide a larger number of deposition gas mixture inlet nozzles and a larger number of longer deposition cartridges, it is only necessary to increase the planar cross section of the cartridge reactor, and if the height of the deposition cartridge is increased, other cartridge reactor The production capacity of the cartridge reactor can be significantly increased without significant redesign of the parts. Easily changing the magnitude of directional solidification, which would be a challenge with external heating of the molten material, can be achieved by heating and pulling under control the deposition cartridge from the molten silicon.

Claims (2)

In a method for producing a substance by chemical vapor deposition,
a. Providing a container that can be sealed from the surrounding space;
b. Providing a deposition surface that can be heated and disposed within the container;
c. Providing a flow of a deposition gas mixture flowing into the vessel, preventing the precipitation gas mixture from flowing in the space surrounding the vessel;
d. Providing a flow of exhaust gas flowing out of the container, preventing the exhaust gas from flowing in the space surrounding the container;
e. Disposing the deposition surface inside the container, sealing the container from the surrounding space, heating the deposition surface, pouring the deposition gas mixture into the container, pouring the exhaust gas out of the container, As a result, the crust of the material is deposited on the deposition surface and substantially fills the cavity volume of the container;
f. Stopping the flow of the precipitation gas mixture entering the vessel and purging it, and continuing the production cycle with any of the following steps, the steps comprising:
i. If the deposition surface is made of the same material as the deposited material, simply unseal the container and collect the container substantially filled with a crust of the material for subsequent processing. The process of
ii. Where the precipitation surface is made of a material having a higher melting temperature than the material to be produced or a combination thereof, and a solid product is desired,
1. Further heating the deposition surface to or above the melting temperature of the material, thereby liquefying a thin layer of the material at the interface with the deposition surface and peeling the crust of the material;
2. Unsealing the container and separating the heated deposition surface from the release crust of the substance in the container; and
3. A step of recovering the container substantially filled with a crust of the substance for subsequent processing;
iii. If the precipitation surface is made of a material having a higher melting temperature than the material to be produced or a combination thereof, and a molten product is desired,
1. Further heating the precipitation surface to or above the melting temperature of the material and maintaining the precipitation surface in contact with the material until the material melts;
2. Unsealing the container and separating the heated deposition surface from the molten material in the container; and
3. Recovering the container substantially filled with the molten material for subsequent processing, and
iv. If the precipitation surface is made of a material having a higher melting temperature than the material to be produced, or a combination thereof, and a crystalline product is desired,
1. Further heating the precipitation surface to or above the melting temperature of the material and maintaining the precipitation surface in contact with the material until the material melts;
2. Unsealing the vessel and pulling the heated deposition surface away from the molten material at a controlled rate such that the material is specifically cooled and crystallized; and
3. Comprising a step of recovering the container substantially filled with the crystalline material for subsequent processing;
A method comprising: In a method and reactor for producing a substance by chemical vapor deposition,
a. Providing a reactor that can be sealed from the surrounding space;
b. Providing a container that can be placed inside the reactor and can be sealed from the rest of the space inside the reactor;
c. Providing a deposition surface that can be heated and disposed within the container;
d. Preparing a flow of the deposition gas mixture from the outside of the reactor to the inside of the vessel in the reactor, so that the deposition gas mixture does not flow in the remaining portion of the space inside the reactor. And the stage of
e. Preparing a flow of exhaust gas from the interior of the vessel in the reactor to the exterior of the reactor, wherein the exhaust gas is prevented from flowing in the remaining portion of the space within the reactor. Stages,
f. Placing the vessel inside the reactor and sealing the reactor from the surrounding space;
g. Placing the deposition surface inside the vessel and sealing the vessel from the remaining portion of the space inside the reactor;
h. The deposition surface is heated, the deposition gas mixture is poured into the container, and the exhaust gas is poured out from the container, so that the crust of the substance is deposited on the deposition surface, and the cavity volume of the container is increased. Substantially filling, and
i. Stopping the flow of the precipitation gas mixture entering the vessel and purging it, and continuing the production cycle with any of the following steps, the steps comprising:
i. If the deposition surface is made of the same material as the deposited material, simply unsealing the container, unsealing the reactor, and filling the container substantially filled with a crust of the material , A process of collecting for subsequent processing,
ii. Where the precipitation surface is made of a material having a higher melting temperature than the material to be produced or a combination thereof, and a solid product is desired,
1. Further heating the deposition surface to or above the melting temperature of the material, thereby liquefying a thin layer of the material at the interface with the deposition surface and peeling the crust of the material;
2. 2. unsealing the container and pulling the heated deposition surface away from the release crust of the substance in the container; A step comprising: unsealing the reactor and recovering the container substantially filled with a crust of the substance for subsequent processing;
iii. If the precipitation surface is made of a material having a higher melting temperature than the material to be produced or a combination thereof, and a molten product is desired,
1. Further heating the precipitation surface to or above the melting temperature of the material and maintaining the precipitation surface in contact with the material until the material melts;
2. 2. unsealing the container and pulling the heated deposition surface away from the molten material in the container; Unsealing the reactor and recovering the container substantially filled with the molten material for subsequent processing, and
iv. If the precipitation surface is made of a material having a higher melting temperature than the material to be produced, or a combination thereof, and a crystalline product is desired,
1. Further heating the deposition surface to or above the melting temperature of the material, thereby liquefying a thin layer of the material at the interface with the deposition surface and peeling the crust of the material;
2. A procedure for melting the substance by any of the following procedures,
Those treatments are
a. Treatment to melt using the deposition surface by keeping the heated deposition plate in contact with the material until the material is melted; and
b. A process of melting using a heating device that is external to the vessel but internal to the reactor,
The melting treatment is
i. Unsealing the container, separating the heated deposition surface from the release crust of the substance in the container; and
ii. A procedure comprising melting the substance in the container using the heating device external to the container but internal to the reactor;
further,
3. A procedure for crystallizing the molten material by any of the following treatments:
Those treatments are
a. Treatment to unseal the container and pull the heated deposition surface away from the molten material at a controlled rate so that the material is specifically cooled and crystallized;
b. A treatment that heats the material at a controlled rate such that specific cooling and crystallization occurs by the heating device external to the vessel but internal to the reactor;
c. Prepare a cooling device that is external to the vessel but internal to the reactor and that cools the material at a controlled rate such that specific cooling and crystallization occurs on the material. ,and,
d. A procedure comprising immersing in the molten material and using a rotary pulling rod that draws from the material at a controlled rate such that crystallization occurs; and
further,
4). A step comprising: unsealing the reactor and recovering the container substantially filled with the crystalline material for subsequent processing;
Including a stage,
A method and reactor comprising:

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