US20110247364A1 - Process for producing multicrystalline silicon ingots by the induction method and apparatus for carrying out the same - Google Patents

Process for producing multicrystalline silicon ingots by the induction method and apparatus for carrying out the same Download PDF

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US20110247364A1
US20110247364A1 US13/139,612 US200913139612A US2011247364A1 US 20110247364 A1 US20110247364 A1 US 20110247364A1 US 200913139612 A US200913139612 A US 200913139612A US 2011247364 A1 US2011247364 A1 US 2011247364A1
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Prior art keywords
ingot
heating equipment
equipment set
silicon
movable bottom
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Inventor
Sergii Beringov
Volodymyr Onischenko
Anatoliy Shkulkov
Yurii Cherpak
Sergii Pozigun
Stepan Marchenko
Andrii Shevchuk
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SOLIN DEVELOPMENT BV
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PILLAR Ltd
SLICIO SOLAR SAU
TOVARYSTVO 2 OBMEZHENOYU VIDPOVIDAINISTYU "TESYS"
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Priority claimed from UAA200814479A external-priority patent/UA92392C2/uk
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Assigned to PILLAR LTD., SLICIO SOLAR, S.A.U., TOVARYSTVO 2 OBMEZHENOYU VIDPOVIDAINISTYU "TESYS" reassignment PILLAR LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ONISCHENKO, VOLODYMYR, BERINGOV, SERGII, MARCHENKO, STEPAN, SHKULKOV, ANATOLIY, CHERPAK, YURII, POZIGUN, SERGII, SHEVCHUK, ANDRII
Publication of US20110247364A1 publication Critical patent/US20110247364A1/en
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Assigned to SOLIN DEVELOPMENT B.V. reassignment SOLIN DEVELOPMENT B.V. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BSB COOPERATIEVE U.A.
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    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B28/00—Production of homogeneous polycrystalline material with defined structure
    • C30B28/04—Production of homogeneous polycrystalline material with defined structure from liquids
    • C30B28/06—Production of homogeneous polycrystalline material with defined structure from liquids by normal freezing or freezing under temperature gradient
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/02—Use of electric or magnetic effects
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/04—Influencing the temperature of the metal, e.g. by heating or cooling the mould
    • B22D27/045—Directionally solidified castings
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/02—Silicon
    • C01B33/037—Purification
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
    • C30B11/003—Heating or cooling of the melt or the crystallised material
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
    • C30B11/006—Controlling or regulating
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/02—Elements
    • C30B29/06—Silicon
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B30/00—Production of single crystals or homogeneous polycrystalline material with defined structure characterised by the action of electric or magnetic fields, wave energy or other specific physical conditions
    • C30B30/04—Production of single crystals or homogeneous polycrystalline material with defined structure characterised by the action of electric or magnetic fields, wave energy or other specific physical conditions using magnetic fields
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B35/00—Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
    • C30B35/005—Transport systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy

Definitions

  • the invention relates to producing polycrystalline silicon, particularly to producing multicrystalline silicon by the induction method, and can be used in manufacture of solar cells from multicrystalline silicon.
  • Crystal silicon is used for producing solar cells to converse solar energy into electrical energy.
  • Single-crystal silicon is usually used for this purpose.
  • multicrystalline silicon polycrystalline silicon formed by the large crystals, so called multicrystalline silicon, allowed to reach the efficiency of converting solar energy into electric energy close to that of single-crystal silicon.
  • Production capacity of equipment for producing multicrystalline silicon is several times higher than for single-crystal silicon, and its technology is easier than the technology for obtaining single-crystal silicon.
  • the use of multicrystalline silicon enables to reduce the cost of solar panels and to start their production on the industrial level.
  • a process for producing multicrystalline silicon ingots by the induction method comprising a continuous supplying, and an induction melting of polycrystalline lump silicon batch material in a silicon melt-pool on a movable bed of a water-cooled crucible, casting the molten silicon to the shape of the melting space, and subsequent crystallizing a multicrystalline silicon ingot (U.S. Pat. No. 4,572,812).
  • the melt-pool is contained within a skull formed using the water-cooled crucible consisting of the vertical copper tube sections cooled with water.
  • the copper sections are separated by gaps and form a melting volume enclosed on the perimeter. Gaps between the sections permit inductor electromagnetic field to penetrate into the crucible melting volume.
  • the melting volume can be shaped as a circle, a square, or a rectangle.
  • a melt-pool fills up the entire transverse area of the crucible, thus resulting both in melting and casting of the silicon pool as an ingot of specific transverse size and shape.
  • the speed, of ingot movement corresponds to the speed of the lump batch melting in the upper part of the melt-pool.
  • a disadvantage of the above process for producing multicrystalline silicon ingots by induction method is the appearance of thermal stress in the ingot resulting in lower quality degradation of plates produced using such ingot. Thermal stresses in the ingot and in the plates made of such ingot results in decreased efficiency of energy conversion by solar cells formed of these plates. In addition, the output factor of good plates also decreases due to their rupture caused by thermal stresses.
  • the identified problems are resolved by the process of producing multicrystalline silicon ingots by induction method that is described in EP, 1254861.
  • this known process it is provided the additional heating of a silicon ingot obtained in the process of continuous casting by using the heaters located underneath the water-cooled crucible, and additional heating of the ingot by plasma discharge of a plasmatron located above the water-cooled crucible. At the same time, the plasma discharge is scanning over the pool surface.
  • Electric circuit for the plasmatron is looped at the silicon ingot through a special contact that is arranged underneath the place where the ingot exits the processing chamber.
  • the method provides reducing the temperature gradient over the silicon ingot radius down to 9 . . . 7° C./m, and thus results in achievement of a high efficiency (14.2 . . . 14.5%) of converting solar energy into electric energy for the plates made of this ingot.
  • concentration of impurities in the melt-pool is fitting with the concentration of impurities in the loaded batch.
  • Concentration of impurities in an ingot is defined by the segregation factor of each impurity. Inasmuch as the segregation factor for typical impurities in the source material is lower than 1, concentration of each impurity in the ingot is lower than its concentration in melt. As much as the ingot grows longer, concentration of impurities in the melt-pool increases due to their accumulation, and consequently their concentration in the produced multicrystalline ingot also increases.
  • the most relevant process to the claimed invention is a process of producing multicrystalline silicon ingots by the induction method described in EP, 1754806.
  • This method comprises charging and start-up heating a lump silicon charge material in a controlled atmosphere on a movable bottom within the melting space of a water-cooled crucible, creating a bath of molten silicon, and subsequently melting and casting the molten silicon to the shape of the melting space, crystallizing a multicrystalline silicon ingot, and controllably cooling the silicon ingot using a heating equipment set.
  • the multicrystalline silicon ingot cools down, it is removed from the processing chamber via a gas seal which prevents atmospheric air from penetrating into the chamber, and is cut down into cut-to-length sections by a cutter.
  • the melting process is stopped, the melt-pool is crystallized, and a separation device is drawn down into the crystallized ingot in the melting volume of the water-cooled crucible to block the melting volume and prevent impure silicon from the bottom surface of the separation device from entering the upper surface.
  • the initial lump batch of silicon is supplied onto the upper surface of the separation device, and the operations are repeated starting from supply and start heating of silicon lump batch.
  • the prior art method has the following drawbacks.
  • the entire upper part of the ingot—approximately 2.5 m long—located inside the heating equipment and processing chamber (above the gas seal) should run the step of controlled cooling.
  • the controlled cooling is carrying out in the mode similar to the one used for the whole ingot and this step takes approximately 30 hours.
  • each step of inserting the separation device into the furnace melting volume and resuming the process of melting and casting takes about 7.2 hours. During this period, induction melting and casting of the pool is not provided.
  • the step of inserting a separation device into a melting volume requires high precision, since even a small misalignment error during the installation of the separation device may result in its jamming and damage of the water-cooled crucible, consequently resulting in the compulsory termination of melting and casting.
  • EP, 1754806 describes a system for producing multicrystalline silicon ingots comprising a chamber with a built-in water-cooled crucible with a movable bottom, and a heating equipment set for controlled cooling of the ingot.
  • the water-cooled crucible includes the isolated sections made of electricity- and heat-conducting material—typically, copper—cooled by a water flow.
  • the water-cooled crucible is enveloped by an inductor and connected to a batch bin.
  • the movable bottom is designed to move up and down along the heating equipment set.
  • the system is provided with a separation device (divider) that can be installed on a crystallized ingot in the melting volume of the water-cooled crucible. Subsequent heating of a silicon lump batch, melting and casting can take place above the upper surface of the separation device.
  • divider separation device
  • a drawback of the current system is a low production capacity, especially when a batch with a high content of impurities is used.
  • a batch bin is connected with a chamber inside which the following equipment is installed: a water-cooled crucible enveloped by an inductor, a device for start-up heating of silicon lump batch, a movable bottom with a rod connected to moving equipment, and a controlled cooling compartment with a heating equipment set located underneath the water-cooled crucible.
  • the movable bottom is arranged to move up and down along the heating equipment set.
  • the availability of heating equipment enables to control a speed of cooling the produced ingot as it moves continuously inside the controlled cooling compartment, thus achieving decrease of temperature gradients over the ingot length within 5 to 10° C./cm.
  • a drawback of the prior art apparatus is degradation of ingot quality and decrease of production output when using silicon lump batch with a high content of impurities, for example, metallurgical-grade silicon characterized by an increased content of iron (Fe) and aluminum (Al) admixtures. Operational capabilities of solar cells decreases when a content of Fe exceeds 0.01 ppmw, and Al—0.1 ppmw. Due to segregating the identified impurities, satisfactory quality of silicon is maintained within a limited length of the produced multicrystalline silicon ingot, not more than 2-4 m, depending on the amount of impurities. However, upon producing the ingots of the identified length time period required to remove the ingot from the water-cooled crucible and the controlled cooling compartment increases relative to the time of induction melting and casting, and the equipment capacity decreases.
  • impurities for example, metallurgical-grade silicon characterized by an increased content of iron (Fe) and aluminum (Al) admixtures. Operational capabilities of solar cells decreases when a content of Fe exceed
  • An object of the invention is to improve the process for producing multicrystalline silicon ingots by the induction which would lead to increased output of multicrystalline silicon suitable for producing solar cells due to the proposed relocation of an ingot and heating equipment with a movable bottom during controlled cooling.
  • Another object of the invention is to upgrade the apparatus for producing multicrystalline silicon which due to the proposed design would increase production capacity of obtaining multicrystalline silicon ingots suitable for producing solar cells.
  • the proposed method of obtaining multicrystalline silicon ingots using induction comprises the steps of charging and start-up heating a lump silicon charge material in a controlled atmosphere on a movable bottom within the melting space of a water-cooled crucible, creating a bath of molten silicon, and subsequently melting and casting the molten silicon to the shape of the melting space, crystallizing a multicrystalline silicon ingot, and controllably cooling the silicon ingot using a heating equipment set, terminating the steps of melting and casting when the content of impurities in the molten silicon becomes critical, and repeating the process steps starting from the steps of charging and start-up heating the lump silicon charge material.
  • the step of crystallizing the remaining part of the multicrystalline silicon ingot is finished as the whole ingot is controllably cooled; upon completion of crystallization, the multicrystalline silicon ingot is removed together with the movable bottom and the heating equipment set and further cooled in a controllable manner; and at the same time, another heating equipment set including another movable bottom is supplied to the vacated space; then said another movable bottom is moved into the water-cooled crucible; and the process steps are repeated in order to produce the next ingot.
  • a simultaneous removal of the multicrystalline silicon ingot with the heating equipment set and the supply of another heating equipment set together with another movable bottom is done by a 180-degree rotary turn is the preferred embodiment of the claimed process.
  • an apparatus for carrying out the process for producing multicrystalline silicon ingots by the induction method comprising a chamber connected to a charge bin, the chamber including a water-cooled crucible enveloped by an inductor, a device for start-up heating a lump silicon charge material, and a movable bottom with a rod connected to a movement means, as well as a controlled cooling compartment arranged underneath the water-cooled crucible and including a heating equipment set, the movable bottom being movable up and down along the heating equipment set.
  • the claimed apparatus further comprises a platform installed in the controlled cooling compartment and capable of rotation about the axis whereon said heating equipment set is mounted; and the apparatus further comprising at least one more heating equipment set installed on the platform and another movable bottom arranged in said another heating equipment set together with a rod connected to a suitable movement means therefor.
  • the apparatus may contain two heating equipment sets installed on the platform symmetrical around an axis of rotation. At the same time, each of the heating equipment sets has an algorithm for changing temperature vertically to ensure an established temperature gradient is maintained in the produced multicrystalline silicon ingot.
  • the proposed staging of the controlled cooling of a multicrystalline silicon ingot which can be implemented without interrupting the overall cooling process allows to be flexible in regulating the length of the produced ingot depending on the amount of impurities in the starting batch.
  • the claimed process is effective process, characterized by a high production output of ingots suitable for producing solar batteries, and can be used for batches with a high content of impurities.
  • a reduced period of induction melting downtime, and lack of dependency of a part of the controlled cooling process on melting and casting processes permit to increase capacity of the system for producing multicrystalline silicon.
  • FIG. 1 illustrates the apparatus for producing multicrystalline silicon ingots by the induction method as having two heating equipment sets for controlled cooling of multicrystalline silicon, in which:
  • FIG. 1 is an embodiment of the apparatus at a start-up heating step:
  • FIG. 2 is the apparatus of FIG. 1 at the step of induction melting and casting of a multicrystalline silicon ingot;
  • FIG. 3 illustrates the position of the multicrystalline silicon ingot before movement
  • FIG. 4 illustrates the position of the multicrystalline silicon ingot after movement
  • FIG. 5 is the apparatus of FIG. 1 at the step of induction melting and casting of the next multicrystalline silicon ingot, and removal of the previous multicrystalline silicon ingot
  • FIG. 6 illustrates a chart demonstrating changes of iron concentration over the length of the multicrystalline silicon ingot with a square cross-section (a side is 337 mm long) for the starting material specified in Table.
  • the apparatus for producing multicrystalline silicon ingots by the using induction method as demonstrated on FIG. 1 comprises a chamber 1 connected to a charging bin 2 , a water-cooled crucible 3 enveloped by an inductor 4 .
  • a movable bottom 5 with a rod 6 connected to the movement devices as well as a start-up heating device 7 of lump silicon charge material 8 are installed inside the chamber 1 .
  • the start-up heating device 7 is made of conductive material, e.g., graphite.
  • the water-cooled crucible 3 is made of copper sections cooled with water.
  • a controlled cooling compartment 9 including a heating equipment set 10 and a similar heating equipment set 11 is located in the chamber 1 .
  • the movable bottom 5 is arranged to move vertically along the heating equipment set 10 .
  • the heating equipment set 11 consists of a movable bottom 12 with a rod 13 connected to the corresponding movement devices.
  • the movable bottom 12 can move vertically along the heating equipment set 11 .
  • the heating equipment sets 10 and 11 are installed on a platform 14 .
  • the platform 14 is placed in the controlled cooling compartment 9 , and is able to rotate about axis 15 .
  • the chamber 1 is connected to a discharge device 16 through a gas seal 17 .
  • the apparatus works as follows.
  • the movable bottom 5 is moved toward the water-cooled crucible 3 , and a high-frequency electromagnetic field is created by inductor 4 .
  • the lump silicon charge material 8 is downloaded from charge bin 2 into a melting space 18 created by the water-cooled crucible 3 and the movable bottom 5 .
  • the start-up heating device 7 is inserted into the melting space 18 located inside a high-frequency electromagnetic field created by the inductor 4 .
  • the start-up heating device 7 gets heated up, and the lump silicon charge material 8 warms up and begins melting under the influence of radiated heat and electromagnetic field created by the inductor 4 ( FIG. 1 ).
  • the start-up heating device 7 is removed from the electromagnetic field created by the inductor 4 , while in the melting space 18 a melt-pool 19 is produced in the form of its lateral section. As a result of heat emission along the periphery of melt-pool 19 , the pool is crystallized, and skull is formed which prevents the pool from spilling from the melting space 18 .
  • a lump silicon charge material 8 is permanently supplied onto its surface from the charging bin 2 . The lump silicon charge material 8 melts down, and at the same time, the movable bottom 5 together with the melt-pool 19 with skull is steadily moved downward.
  • the movement is at the speed which allows the melt-pool 19 to remain at the unchanged level relative to the inductor 4 and the water-cooled crucible 3 , crystallization of the multicrystalline silicon ingot 20 being effected continuously in the lower part of the melt-pool.
  • formed multicrystalline silicon ingot 20 is steadily moved down into the controlled cooling compartment 9 toward the heating equipment set 10 , where its controlled cooling is performed and thermal stresses are removed ( FIG. 2 ).
  • the supply of the lump silicon charge material 8 is stopped, the electromagnetic field of the inductor 4 is removed, and the induction melting and pool casting are stopped.
  • the produced multicrystalline silicon ingot 20 is removed from the water-cooled crucible 3 , and placed into the heating equipment set 10 to terminate crystallization ( FIG. 3 ). Then the multicrystalline silicon ingot 20 is transferred together with the movable bottom 5 and the heating equipment set 10 ( FIG. 4 ) by rotating the platform 14 and the controlled cooling of the ingot continues. Such movement can be accomplished, for example, by a 180-degrees rotary turn of the platform 14 around the axis 15 .
  • the heating equipment set 11 with the movable bottom 12 is transferred to the vacated space ( FIG. 4 ).
  • the heating equipment sets 10 and 11 are electrically switched over and the algorithm of temperature regulation is changed accordingly.
  • the movable bottom 12 is transferred to the water-cooled crucible 3 , defining a new melting space 21 , and the process steps are repeated starting from the supply and start-up heating of lump silicon charge material, in order to obtain a next ingot 22 ( FIG. 5 ).
  • the cooled down multicrystalline silicon ingot 20 located inside the heating equipment set 10 is moved upward on the movable bottom 5 into the discharge device 16 .
  • Multicrystalline silicon ingots were obtained using the apparatus with a melting space of a square cross-section and a side length of 340 mm. This apparatus allows to produce multicrystalline silicon ingots with a square cross-section and a side length of 337 mm.
  • metallurgical-grade bulk silicon was used I with the following usual admixtures such as boron (B), phosphorus (P), iron (Fe), and aluminum (Al).
  • B boron
  • P phosphorus
  • Fe iron
  • Al aluminum
  • the content of impurities in the starting material is shown in the Table. Additionally, an alloy was used to maintain specific resistance within the range of 0.8-1.2 Ohm ⁇ cm.
  • the critical content of impurities is reached when the ingot gets 2.0 . . . 2.5 m long, an optimal length of the ingot being 2.0 . . . 2.3 m.
  • a water-cooled crucible is installed and enveloped by 3-turn inductor of 140 mm in height connected to a source of power with an operating frequency of 10 kHz, and a movable bottom made in the form of a square silicon plate of 40 mm thick with a side length of 338 mm which is placed using a thermal insulation disk on a heat-resistant steel platform, and is attached to the rod via a plug-type connection.
  • the first heating equipment set is installed having a heating space of a square cross-section and the side length of 380 mm.
  • the second heating equipment set is installed on the platform, having a heating space of a square cross-section and the side length of 380 mm.
  • the heating space of each heating equipment set is of 2.4 m in height.
  • Each heating equipment set is provided with graphite heater elements connected to the industrial frequency transformer through the current controllers, thus allowing to ensure controlled changes of the temperature field vertically.
  • the second heating equipment set has another movable bottom installed using a thermal insulation disk on a heat-resistant steel platform, and attached to the rod via a plug-type connection.
  • the chamber was vacuumized and filled with argon.
  • high-frequency electromagnetic field was created using the inductor.
  • Lump silicon charge material was loaded into the melting space from a charging bin, and a start-up heating device in the form of a graphite disk was inserted.
  • the start-up heating device was heated up, and under the influence of heat emission and electromagnetic field, lump silicon starting material was heated to a temperature of 800-1100° C., and started melting.
  • the start-up heating device was removed from the inductor electromagnetic field.
  • a melt-pool was formed inside the melting space, which expanded and reached the walls of a cold crucible, i.e. the pool was cast in the form of the water-cooled crucible.
  • the multicrystalline silicon ingot was melted, cast and formed, it was moved down into the heating space of the first heating equipment set, where the controlled cooling and removal of thermal stresses was carried out by warming up the multicrystalline silicon ingot—already crystallized and chilled—mainly in the corners of the ingot.
  • the temperature was raised up to 1200° C. with the following decrease of a temperature with the gradient of no more than 7° C. over the ingot length.
  • the heating equipment sets were exchanged—the second heating equipment set together with the other movable bottom turned out to be underneath the water-cooled crucible, whereas the first heating equipment set with the multicrystalline silicon ingot located inside its heating space occurred in the place where the second heating equipment set used to be. Then both heating equipment sets were connected to the current controllers—the second heating equipment set located under the water-cooled crucible was connected using the melting algorithm, and the first heating equipment set located out of contact with the water-cooled crucible—using the algorithm for the controlled cooling of the multicrystalline ingot. After the multicrystalline ingot had been cooled down to a temperature below 250° C., it was lifted on the movable bottom into the discharge device.
  • the movable bottom located inside the heating space of the second heating equipment set after completion of the platform turning, was transferred to the water-cooled crucible, and the process steps were repeated starting from supplying and start-up heating of the lump charge until obtaining the next ingot.
  • the proposed invention ensures increased output of multicrystalline silicon suitable for solar cell fabrication.
US13/139,612 2008-12-15 2009-12-14 Process for producing multicrystalline silicon ingots by the induction method and apparatus for carrying out the same Abandoned US20110247364A1 (en)

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CN102120579B (zh) * 2011-01-29 2012-10-03 大连隆田科技有限公司 一种电子束高效、连续熔炼提纯多晶硅的方法及设备
CN104805506B (zh) * 2015-03-24 2017-06-16 中国科学院工程热物理研究所 一种基于液态金属强化换热控制坩埚热应力的方法
CN106735078B (zh) * 2016-11-18 2019-07-05 中国科学院金属研究所 一种非晶合金或其复合材料的连续精密成形设备和工艺
CN111230077A (zh) * 2020-03-09 2020-06-05 西北工业大学 高温合金宽调速定向凝固装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6027563A (en) * 1996-02-24 2000-02-22 Ald Vacuum Technologies Gmbh Method and apparatus for the oriented solidification of molten silicon to form an ingot in a bottomless crystallization chamber
EP1754806A1 (en) * 2005-08-18 2007-02-21 Sumco Solar Corporation Method for casting polycrystalline silicon
US7368368B2 (en) * 2004-08-18 2008-05-06 Cree, Inc. Multi-chamber MOCVD growth apparatus for high performance/high throughput
US20080179037A1 (en) * 2006-12-25 2008-07-31 Mitsuo Yoshihara Casting method of silicon ingot and cutting method of the same

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4572812A (en) * 1984-08-13 1986-02-25 The United States Of America As Represented By The Secretary Of Energy Method and apparatus for casting conductive and semiconductive materials
EP0349904B1 (en) 1988-07-05 1994-02-23 Sumitomo Sitix Co., Ltd. Apparatus for casting silicon
JPH07138012A (ja) * 1993-11-16 1995-05-30 Sumitomo Sitix Corp シリコン鋳造装置
US6994835B2 (en) 2000-12-28 2006-02-07 Sumitomo Mitsubishi Silicon Corporation Silicon continuous casting method
CN2715885Y (zh) * 2004-07-08 2005-08-10 上海大学 梯度强磁场单向凝固结晶装置
CN1275724C (zh) * 2004-08-11 2006-09-20 哈尔滨工业大学 多功能冷坩埚电磁精确成形与定向凝固装置
EP1973089B1 (en) * 2005-11-29 2010-12-29 Seiko Instruments Inc. Process for producing display and method of laminating
CN1873062A (zh) * 2006-05-06 2006-12-06 大连理工大学 一种太阳能电池用高纯多晶硅的制备方法和装置
CN101307487B (zh) * 2007-05-16 2010-05-19 佳科太阳能硅(厦门)有限公司 一种连续生产多晶硅锭的定向凝固方法及其装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6027563A (en) * 1996-02-24 2000-02-22 Ald Vacuum Technologies Gmbh Method and apparatus for the oriented solidification of molten silicon to form an ingot in a bottomless crystallization chamber
US7368368B2 (en) * 2004-08-18 2008-05-06 Cree, Inc. Multi-chamber MOCVD growth apparatus for high performance/high throughput
EP1754806A1 (en) * 2005-08-18 2007-02-21 Sumco Solar Corporation Method for casting polycrystalline silicon
US20080179037A1 (en) * 2006-12-25 2008-07-31 Mitsuo Yoshihara Casting method of silicon ingot and cutting method of the same

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US9410266B2 (en) 2016-08-09
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WO2010071614A1 (en) 2010-06-24
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