Replenishing Of Precursor During Growth (e.g., Continuous Method, Zone Pulling) Patents (Class 117/33)
  • Patent number: 11401626
    Abstract: A seeding method for crystal growth comprising: a first seeding step: rotating a crucible with a first rotation speed to grow the crystal to a first length; a second seeding step: gradually increasing the rotation speed of the crucible from the first rotation speed to a second rotation speed, and growing the crystal to a second length; a third seeding step: rotating the crucible with the second rotation speed to growing the crystal to a predicted length. By separating the seeding stage to three steps and gradually increasing the rotation speed in the second step of the crucible, the silicon melt convection is enhanced and the temperature at center of the silicon melt is kept to be not lower than the starting temperature of the seeding. Thereby, the removal of dislocation within the seed crystal can be increased, and the growth problems such as broken or polycrystallization can be prevented.
    Type: Grant
    Filed: January 27, 2021
    Date of Patent: August 2, 2022
    Assignee: Zing Semiconductor Corporation
    Inventors: Weimin Shen, Youshu Lei
  • Patent number: 9683286
    Abstract: A method and process for the production of bulk polysilicon by chemical vapor deposition (CVD) where conventional silicon “slim rods” commonly used in Siemens-type reactors are replaced with shaped silicon filaments of similar electrical properties but larger surface areas, such as silicon tubes, ribbons, and other shaped cross sections. Silicon containing gases, such as chlorosilane or silane, are decomposed and form a silicon deposit on the hot surfaces of the filaments The larger starting surface areas of these filaments ensures a higher production rate without changing the reactor size, and without increasing the number and length of the filaments. Existing reactors need only the adaptation or replacement of filament supports to use the new filaments. The filaments are grown from silicon melt by Edge-defined, Film-fed Growth (EFG) method. This also enables the doping of the filaments and simplification of power supplies for new reactors.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: June 20, 2017
    Assignee: GTAT Corporation
    Inventors: Yuepeng Wan, Santhana Raghavan Parthasarathy, Carl Chartier, Adrian Servini, Chandra P. Khattak
  • Publication number: 20150090178
    Abstract: A method for recharging a crucible with polycrystalline silicon comprises adding flowable chips to a crucible used in a Czochralski-type process. Flowable chips are polycrystalline silicon particles made from polycrystalline silicon prepared by a chemical vapor deposition process, and flowable chips have a controlled particle size distribution, generally nonspherical morphology, low levels of bulk impurities, and low levels of surface impurities. Flowable chips can be added to the crucible using conventional feeder equipment, such as vibration feeder systems and canister feeder systems.
    Type: Application
    Filed: December 3, 2014
    Publication date: April 2, 2015
    Inventors: ARVID NEIL ARVIDSON, TERENCE LEE HORSTMAN, MICHAEL JOHN MOLNAR, CHRIS Tim SCHMIDT, ROGER DALE SPENCER, Jr.
  • Publication number: 20140352605
    Abstract: Making a barium-doped silica crucible includes forming a crucible by introducing into a rotating crucible mold bulk silica grains to form a bulky wall. After heating the interior of the mold to fuse the bulk silica grains, an inner silica grain, doped with barium, is introduced into the crucible. Residual heat or additional heat at least partially melts the inner silica grain, allowing the barium-doped silica layer to fuse to the wall of the crucible to form a glossy inner layer. Next, at least a part of the barium-doped silica layer is roughened. Also described are the crucible made thereby as well as silicon ingots made using the crucibles as described herein.
    Type: Application
    Filed: August 28, 2013
    Publication date: December 4, 2014
    Applicant: Heraeus Shin-Etsu America, Inc.
    Inventors: Michael R. Fallows, Jeffrey S. Bailey, JR., Katsuhiko Kemmochi
  • Patent number: 8764901
    Abstract: Embodiments related to sheet production are disclosed. A melt of a material is cooled to form a sheet of the material on the melt. The sheet is formed in a first region at a first sheet height. The sheet is translated to a second region such that it has a second sheet height higher than the first sheet height. The sheet is then separated from the melt. A seed wafer may be used to form the sheet.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: July 1, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Peter L. Kellerman, Dawei Sun, Brian Helenbrook, David S. Harvey
  • Patent number: 8758507
    Abstract: Techniques for the formation of silicon ingots and crystals using silicon feedstock of various grades are described. A common feature is adding a predetermined amount of germanium to the melt and performing a crystallization to incorporate germanium into the silicon lattice of respective crystalline silicon materials. Such incorporated germanium results in improvements of respective silicon material characteristics, including increased material strength and improved electrical properties. This leads to positive effects at applying such materials in solar cell manufacturing and at making modules from those solar cells.
    Type: Grant
    Filed: November 24, 2010
    Date of Patent: June 24, 2014
    Assignee: Silicor Materials Inc.
    Inventors: Fritz G. Kirscht, Matthias Heuer, Martin Kaes, Kamel Ounadjela
  • Patent number: 8696811
    Abstract: A feed assembly and method of use thereof of the present invention is used for the addition of a high pressure dopant such as arsenic into a silicon melt for CZ growth of semiconductor silicon crystals. The feed assembly includes a vessel-and-valve assembly for holding dopant, and a feed tube assembly, attached to the vessel-and-valve assembly for delivering dopant to a silicon melt. An actuator is connected to the feed tube assembly and a receiving tube for advancing and retracting the feed tube assembly to and from the surface of the silicon melt. A brake assembly is attached to the actuator and the receiving tube for restricting movement of the feed tube assembly and locking the feed tube assembly at a selected position.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: April 15, 2014
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Massoud Javidi, Steve Garner
  • Patent number: 8685162
    Abstract: In one embodiment, a sheet production apparatus comprises a vessel configured to hold a melt of a material. A cooling plate is disposed proximate the melt and is configured to form a sheet of the material on the melt. A first gas jet is configured to direct a gas toward an edge of the vessel. A sheet of a material is translated horizontally on a surface of the melt and the sheet is removed from the melt. The first gas jet may be directed at the meniscus and may stabilize this meniscus or increase local pressure within the meniscus.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: April 1, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Peter L. Kellerman, Gregory D. Thronson, Dawei Sun
  • Patent number: 8685160
    Abstract: Provided is a fullerene thin wires-attached substrate in which fullerene thin wires are vertically aligned relative to the surface of the substrate and which is applicable to catalysts, column materials, chemical synthesis templates, field emission devices, field effect transistors, photonic crystals, etc.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: April 1, 2014
    Assignee: National Institute for Materials Science
    Inventors: Cha Seung, II, Kunichi Miyazawa, Jedeok Kim
  • Patent number: 8652257
    Abstract: A melting furnace, mounted adjacent a growth furnace, comprises a receiving container for melting therein raw material in a particle or powder form falling in it from a feeder. The receiving container accommodates a set of slope-wise plates providing a distributed sliding of partially melted raw material particles over the surface of these plates and their complete melting while moving downward; eventually the melted raw material flows into the crucible of the growth furnace through a conveying tube extending slantingly from the bottom of the receiving container to the crucible through coaxial openings in housings of both furnaces. The rate of feeding is given solely by the feeder, and at continuous feeding the raw material flows continuously by gravity from the feeder to the crucible of the growth furnace, first in a solid state (powder, granules, pellets, etc.) and then in a liquid state.
    Type: Grant
    Filed: February 22, 2010
    Date of Patent: February 18, 2014
    Inventors: Lev George Eidelman, Vladimir Ilya Zheleznyak
  • Patent number: 8647432
    Abstract: A method for making a large surface area silicon filament for production of bulk polysilicon by chemical vapor deposition (CVD) includes melting silicon and growing the filament from the melted silicon by an EFG method using a shaping die. The cross sectional shape of the silicon filament is constant over its axial length to within a tolerance of 10%. In embodiments, a plurality of identical and/or dissimilar filaments are grown simultaneously using a plurality of shaping dies. The filaments can be tubular. Filament cross sections can be annular and/or can include outwardly extending fins, with wall and/or fin thicknesses constant to within 10%. Filaments can be doped with at least one element from groups 3 and 5 of the Periodic Table. The filament can have a length equal to a length of a specified slim rod filament, and a total impedance not greater than the slim rod impedance.
    Type: Grant
    Filed: July 20, 2011
    Date of Patent: February 11, 2014
    Assignee: GTAT Corporation
    Inventors: Yuepeng Wan, Santhana Raghavan Parthasarathy, Carl Chartier, Adrian Servini, Chandra P Khattak
  • Publication number: 20130305982
    Abstract: Provided is a method for manufacturing a silicon carbide single crystal using a solution process including coming a seed crystal substrate for growing silicon carbide into contact with a Si—C alloy solution including at least one additive metal and growing the silicon carbide single crystal on a seed crystal for growing silicon carbide, including feeding a silicon feedstock into an alloy solution when a molar ratio of Si and the additive metal is lower than an initially set value as the reaction progresses. The method increases a crystal growth speed, maintains the growth speed, and prevents the growth from unwillingly stopping when the silicon carbide single crystal is manufactured using a solution growth process.
    Type: Application
    Filed: October 17, 2011
    Publication date: November 21, 2013
    Inventors: Sung Wan Hong, Young Shol Kim
  • Patent number: 8545622
    Abstract: An annealed wafer in which oxygen precipitation is uniform in the substrate plane and a manufacturing method thereof are provided. A nitrogen-doped silicon single crystal substrate pulled at the cooling rate of 4° C./minute or more during crystal growth between 1100 and 1000° C. wherein the nitrogen concentration is 1×1014 to 5×1015 atoms/cm3 and V/G satisfies predetermined conditions serves as a substrate, and the substrate is subjected to heat treatment in a non-oxidative atmosphere.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: October 1, 2013
    Assignee: Siltronic AG
    Inventors: Katsuhiko Nakai, Koji Fukuhara
  • Patent number: 8454746
    Abstract: Silicon single crystals are prepared from molten granules, by producing a first volume of molten silicon between a growing single crystal and the lower end of a silicon conical tube which is closed at its lower end, and encloses a central opening of a rotating silicon plate below which the tube extends, by means of a first induction heating coil arranged below the plate; producing a second volume of molten silicon by a second induction heating coil arranged above the plate; melting the lower end of the tube to form a passage for the second volume of molten silicon, the passage produced at a point in time when the second volume is not yet present or is less than double the volume of the first volume; and crystallizing monocrystalline silicon on the growing single crystal with consumption of molten silicon from the first and the second volume.
    Type: Grant
    Filed: January 18, 2011
    Date of Patent: June 4, 2013
    Assignee: Siltronic AG
    Inventors: Wilfried von Ammon, Ludwig Altmannshofer
  • Patent number: 8414701
    Abstract: In this method for manufacturing a silicon single crystal, when growing the silicon single crystal, in order to control the V/G value with high accuracy so as to yield a desired defect-free region, it is important to conduct the pulling at a constant pulling rate. In the method for pulling a silicon single crystal in the present invention, in order to control the V/G value with high accuracy, the distance ?t between the melt surface of the silicon melt and the heat shielding member that is disposed so as to oppose to and to partially cover this melt surface is continuously measured while pulling (growing) the silicon single crystal.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: April 9, 2013
    Assignee: Sumco Corporation
    Inventor: Keiichi Takanashi
  • Patent number: 8361223
    Abstract: Provided is a method for reliably and easily measuring a liquid level by selecting an optimal reflection method from among a plurality of reflection methods, depending on growing conditions of a pulled single crystal. The method comprises: setting a plurality of measuring methods having different ways of determining the liquid level; creating, in advance, information that associates with a gap between the outer peripheral face of the single crystal and a predetermined position located between a heat shield and the outer peripheral face of the single crystal; determining the gap in accordance with manufacturing conditions; selecting a measuring method associated to the determined gap, on the basis of the information; and measuring the liquid level of a melt surface in use of the selected measuring method.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: January 29, 2013
    Assignee: Sumco Techxiv Corporation
    Inventors: Toshio Hayashida, Ayumi Kihara, Takuaki Takami
  • Patent number: 8268077
    Abstract: An upper heater for use in the production of a single crystal, the upper heater having electrodes to which a current is supplied and a heat generating section which generates heat by resistance heating are provided, the upper heater being used when a single crystal is produced by a Czochralski method, the upper heater being placed above a graphite heater which is placed so as to surround a crucible containing silicon melt, wherein the heat generating section is ring-shaped and is placed so as to surround the crucible, and has slits formed from the inside and the outside of the heat generating section in a horizontal direction. As a result, the upper heater controls a crystal defect of the single crystal efficiently and improves the oxygen concentration controllability.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: September 18, 2012
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Kiyotaka Takano
  • Patent number: 8262795
    Abstract: An apparatus and method for producing a crystalline ribbon continuously from a melt pool of liquid feed material, e.g. silicon. The silicon is melted and flowed into a growth tray to provide a melt pool of liquid silicon. Heat is passively extracted by allowing heat to flow from the melt pool up through a chimney. Heat is simultaneously applied to the growth tray to keep the silicon in its liquid phase while heat loss is occurring through the chimney. A template is placed in contact with the melt pool as heat is lost through the chimney so that the silicon starts to “freeze” (i.e. solidify) and adheres to the template. The template is then pulled from the melt pool thereby producing a continuous ribbon of crystalline silicon.
    Type: Grant
    Filed: October 9, 2009
    Date of Patent: September 11, 2012
    Assignee: AMG Idealcast Solar Corporation
    Inventor: Roger F. Clark
  • Patent number: 8257496
    Abstract: A weighing system is provided for a continuous Czochralski process that accurately measures the weight of the crucible and melt during crystal growth to control the introduction of feedstock in order to keep the weight approximately constant. The system can measure the weight of the crucible while the crucible is rotating, and is insensitive to vibrations of the melt surface as well as variable torques on the crucible shaft induced by the rotation. The system also measures the weight of the crucible and its contents in order to control the amount of feedstock recharged after an ingot is withdrawn.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: September 4, 2012
    Assignee: Solaicx, Inc.
    Inventors: David L. Bender, Gary Janik, Roy P. Crawford, David E. A. Smith
  • Patent number: 8236104
    Abstract: A single-crystal manufacturing apparatus comprising at least: a main chamber configured to accommodate a crucible; a pulling chamber continuously provided above the main chamber, the pulling chamber into which a grown single crystal is pulled and accommodated; a gas inlet provided in the pulling chamber; a gas flow-guide cylinder downwardly extending from a ceiling of the main chamber; and a heat-insulating ring upwardly extending from a lower end portion of the gas flow-guide cylinder with a diameter of the heat-insulating ring increased so as to surround an outside of the gas flow-guide cylinder, wherein at least one window is provided in a region between 50 and 200 mm from a lower end of the gas flow-guide cylinder, and an opening area of the window accounts for 50% or more of a surface area of the region between 50 and 200 mm from the lower end of the gas flow-guide cylinder.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: August 7, 2012
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Satoshi Soeta, Toshifumi Fujii
  • Patent number: 8221550
    Abstract: A process for producing a single crystal of semiconductor material, in which fractions of a melt, are kept in liquid form by a pulling coil, solidify on a seed crystal to form the growing single crystal, and granules are melted in order to maintain the growth of the single crystal. The melting granules are passed to the melt after a delay. There is also an apparatus which Is suitable for carrying out the process and has a device which delays mixing of the molten granules and of the melt.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: July 17, 2012
    Assignee: Siltronic AG
    Inventor: Wilfried von Ammon
  • Patent number: 8211228
    Abstract: The present invention is a method for producing a single crystal that is a multi-pulling method for pulling a plurality of single crystals from a raw material melt in a same crucible in a chamber by a Czochralski method, comprising steps of: pulling a single crystal from a raw material melt ; then additionally charging polycrystalline raw material in a residual raw material melt without turning off power of a heater, and melting the polycrystalline raw material; then pulling a next single crystal; and repeating the steps and thereby pulling the plurality of single crystals.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: July 3, 2012
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Ryoji Hoshi, Takahiro Yanagimachi
  • Publication number: 20120160156
    Abstract: A method for recharging raw material polycrystalline silicon which enables large chunks of polycrystalline silicon to be recharged to a CZ ingot growth process while preventing the CZ crucible from being damaged and restricting a decline of the dislocation free rate and the quality of the grown ingot. Polycrystalline silicon chunks are recharged by first forming cushioning layer silicon of smaller chunks. The cushioning layer of polycrystalline silicon chunks are deposited on a surface of the residual silicon melt in a crucible. Subsequently, large-sized polycrystalline silicon chunks are introduced onto the cushioning layer, the cushioning layer cushioning the impact due to dropping of the large-sized polycrystalline silicon chunks.
    Type: Application
    Filed: December 19, 2011
    Publication date: June 28, 2012
    Applicant: SILTRONIC AG
    Inventors: Hideo Kato, Satoko Yoshimura, Takeshi Ninomiya
  • Patent number: 8124041
    Abstract: A process for producing silicon comprises the steps of a reduction step [1] of depositing silicon by reacting chlorosilanes and hydrogen in a reactor under heat and discharging an exhaust gas that contains hydrogen, oligomers of silanes, and a silicon powder; a carring step [2] of carrying the exhaust gas that has been exhausted in the step [1] while keeping a temperature of the exhaust gas at not less than 105° C.; a removal step [3] of supplying the exhaust gas that has been carried in the step [2] to a filter at a temperature of not less than 105° C. and discharging the exhaust gas from the filter at a temperature of not less than 105° C. to remove the silicon powder from the exhaust gas and give a mixed gas that contains the hydrogen and the oligomers of silanes; and a separation step [4] of cooling the mixed gas that has been obtained in the step [3] to separate the hydrogen as a gas phase from the mixed gas.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: February 28, 2012
    Assignee: Tokuyama Corporation
    Inventors: Manabu Sakida, Satoru Wakamatsu
  • Publication number: 20110286906
    Abstract: A method for recharging a crucible with polycrystalline silicon comprises adding flowable chips to a crucible used in a Czochralski-type process. Flowable chips are polycrystalline silicon particles made from polycrystalline silicon prepared by a chemical vapor deposition process, and flowable chips have a controlled particle size distribution, generally nonspherical morphology, low levels of bulk impurities, and low levels of surface impurities. Flowable chips can be added to the crucible using conventional feeder equipment, such as vibration feeder systems and canister feeder systems.
    Type: Application
    Filed: August 3, 2011
    Publication date: November 24, 2011
    Inventors: Arvid Neil Arvidson, Terence Lee Horstman, Michael John Molnar, Chris Tim Schmidt, Roger Dale Spencer, JR.
  • Patent number: 8021483
    Abstract: A method for recharging a crucible with polycrystalline silicon comprises adding flowable chips to a crucible used in a Czochralski-type process. Flowable chips are polycrystalline silicon particles made from polycrystalline silicon prepared by a chemical vapor deposition process, and flowable chips have a controlled particle size distribution, generally nonspherical morphology, low levels of bulk impurities, and low levels of surface impurities. Flowable chips can be added to the crucible using conventional feeder equipment, such as vibration feeder systems and canister feeder systems.
    Type: Grant
    Filed: November 14, 2002
    Date of Patent: September 20, 2011
    Assignee: Hemlock Semiconductor Corporation
    Inventors: Arvid Neil Arvidson, Terence Lee Horstman, Michael John Molnar, Chris Tim Schmidt, Roger Dale Spencer, Jr.
  • Patent number: 8016942
    Abstract: A metal fluoride single crystal pulling apparatus that upward pulling initiation through termination, in the state of shallow melt capable of highly effective inhibition of scatterer formation, can perform stable growth of single crystal and can suppress any mixing of air bubbles and occurrence of crystal break during crystal growth, etc; and a process for producing a metal fluoride single crystal therewith. As a crucible for accommodating a melt of raw metal fluoride, use is made of a double structured crucible composed of an outer crucible and an inner crucible. In the upward pulling of single crystal, the accommodation depth of inner crucible relative to the outer crucible is increased in accordance with any decrease of melt accommodated in the inner crucible according to the growth of single crystal, so that the melt accommodated in the outer crucible is fed into the inner crucible to thereby maintain the amount of melt accommodated in the inner crucible within a given range.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: September 13, 2011
    Assignee: Tokuyama Corporation
    Inventors: Teruhiko Nawata, Ken Yasumura, Hiroyuki Yanagi, Eiichi Nishijima
  • Patent number: 7922817
    Abstract: A feed assembly and method of use thereof of the present invention is used for the addition of a high pressure dopant such as arsenic into a silicon melt for CZ growth of semiconductor silicon crystals. The feed assembly includes a vessel-and-valve assembly for holding dopant, and a feed tube assembly, attached to the vessel-and-valve assembly for delivering dopant to a silicon melt. An actuator is connected to the feed tube assembly and a receiving tube for advancing and retracting the feed tube assembly to and from the surface of the silicon melt. A brake assembly is attached to the actuator and the receiving tube for restricting movement of the feed tube assembly and locking the feed tube assembly at a selected position.
    Type: Grant
    Filed: April 24, 2008
    Date of Patent: April 12, 2011
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Massoud Javidi, Steve Garner
  • Patent number: 7887633
    Abstract: Techniques for the formation of silicon ingots and crystals using silicon feedstock of various grades are described. Common feature is adding a predetermined amount of germanium to the melt and performing a crystallization to incorporate germanium into the silicon lattice of respective crystalline silicon materials. Such incorporated germanium results in improvements of respective silicon material characteristics, mainly increased material strength. This leads to positive effects at applying such materials in solar cell manufacturing and at making modules from those solar cells. A silicon material with a germanium concentration in the range (50-200) ppmw demonstrates an increased material strength, where best practical ranges depend on the material quality generated.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: February 15, 2011
    Assignee: Calisolar, Inc.
    Inventors: Fritz Kirscht, Vera Abrosimova, Matthias Heuer, Anis Jouini, Dieter Linke, Martin Kaes, Jean Patrice Rakotoniaina, Kamel Ounadjela
  • Patent number: 7867334
    Abstract: A silicon casting apparatus for producing polycrystal silicon ingot by heating a silicon melt (8) held in a mold (4) from above by a heater (3) and cooling it from below while changing the heat exchange area of a heat exchange region (HE), defined between a pedestal (5) having the mold (4) placed thereon and a bottom cooling member (6), in such a manner as to keep pace with the rise of the solid-liquid interface of the silicon melt (8), thereby causing unidirectional solidification upward along the mold (4); and a method of producing polycrystal silicon ingot using such apparatus. According to this production method, the temperature gradient given to the silicon melt (8) can be maintained at constant by adjusting the heat exchange area, so that polycrystal silicon ingot having good characteristics can be produced with good reproducibility.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: January 11, 2011
    Assignee: Kyocera Corporation
    Inventor: Youhei Sakai
  • Patent number: 7799131
    Abstract: The present invention provides a method for the continuous production of semiconductor ribbons by growth from a linear molten zone. The creation of the molten zone is achieved by application of an electric current, direct or alternating, parallel to the surface of the ribbon and perpendicular to the direction of growth, and intense enough to melt the said material, preferably using electrodes of the said material. The molten zone is fed by transference of the material, in the liquid state, from one or more reservoirs, where melting of the feedstock occurs. Preferably, the said electrodes and the said reservoir(s) are only constituted by the said material, thus avoiding contamination by foreign materials. The present invention is applicable, for example, in the industry of silicon ribbons production for photovoltaic application.
    Type: Grant
    Filed: April 15, 2004
    Date of Patent: September 21, 2010
    Assignee: Faculdade de Ciencias Da Universidade de Lisboa
    Inventors: António Vallêra, João Serra, Jorge Maia Alves, Miguel Brito, Roberto Gamboa, João Henriques
  • Patent number: 7708830
    Abstract: A method for the production of a silicon single crystal by pulling the single crystal, according to the Czochralski method, from a melt which is held in a rotating crucible, the single crystal growing at a growth front, heat being deliberately supplied to the center of the growth front by a heat flux directed at the growth front. The method produces a silicon single crystal with an oxygen content of from 4*1017 cm?3 to 7.2*1017 cm?3 and a radial concentration change for boron or phosphorus of less than 5%, which has no agglomerated self-point defects. Semiconductor wafers are separated from the single crystal. These semiconductor wafers have may have agglomerated vacancy defects (COPs) as the only self-point defect type or may have certain other defect distributions.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: May 4, 2010
    Assignee: Siltronic AG
    Inventors: Wilfried Von Ammon, Janis Virbulis, Martin Weber, Thomas Wetzel, Herbert Schmidt
  • Patent number: 7704318
    Abstract: When growing a silicon single crystal free of grown-in defects based on the CZ method, the crystal is pulled out at a critical pulling rate at which a ring-shaped OSF occurrence region vanishes in a center portion of the crystal by using a hot zone structure in which a temperature gradient Gc in a center portion of the crystal is equal to or greater than a temperature gradient Ge in a peripheral portion of the crystal, while supplying an inert gas including hydrogen to an interior of a pulling furnace. The critical pulling rate at which the ring-shaped OSF occurrence region vanishes in the center portion of the crystal is increased, and single crystals free of grown-in defects in which dislocation clusters and COPs can be grown by pulling at a pulling rate higher than that of the prior art.
    Type: Grant
    Filed: February 25, 2004
    Date of Patent: April 27, 2010
    Assignee: Sumco Corporation
    Inventors: Masataka Hourai, Wataru Sugimura, Toshiaki Ono, Tadami Tanaka
  • Patent number: 7691199
    Abstract: A melter assembly supplies a charge of molten source material to a crystal forming apparatus for use in forming crystalline bodies. The melter assembly comprises a housing and a crucible located in the housing. A heater is disposed relative to the crucible for melting solid source material received in the crucible. The crucible has a nozzle to control the flow of molten source material such that a directed flow of molten source material can be supplied to the crystal forming apparatus at a selected flow rate.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: April 6, 2010
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: John Davis Holder
  • Patent number: 7655089
    Abstract: A process for producing a single crystal of semiconductor material, in which fractions of a melt, are kept in liquid form by a pulling coil, solidify on a seed crystal to form the growing single crystal, and granules are melted in order to maintain the growth of the single crystal. The melting granules are passed to the melt after a delay. There is also an apparatus which Is suitable for carrying out the process and has a device which delays mixing of the molten granules and of the melt.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: February 2, 2010
    Assignee: Siltronic AG
    Inventor: Wilfried von Ammon
  • Patent number: 7465351
    Abstract: A method of servicing multiple crystal forming apparatus with a single melter assembly is provided. The method includes the steps of positioning the melter assembly relative to a first crystal forming apparatus for delivering molten silicon to a crucible of the first apparatus. A heater in the melter assembly is operated to melt source material in a melting crucible. A stream of molten source material is delivered from the melter assembly to the first crystal forming apparatus. The melter assembly is positioned relative to a second crystal forming apparatus for delivering molten silicon to a crucible of the second apparatus. A stream of molten source material is transferred from the melter assembly to the second crystal forming apparatus.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: December 16, 2008
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: John Davis Holder
  • Patent number: 7291222
    Abstract: The invention is directed to apparatus and methods for measuring and for reducing dust in granular polysilicon. In one aspect, a system includes a process vessel having a vacuum port for pulling dust from the polysilicon. Another system of the invention includes a baffle tube for receiving a polysilicon flow. A measuring system includes a manifold and filter for separating and measuring the dust from a flow of polysilicon. The invention is also directed to methods of using the systems, to methods of manufacturing and packaging granular polysilicon, and to a supply of granular polysilicon.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: November 6, 2007
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: John D. Holder, Hariprasad Sreedharamurthy, John D. Hilker
  • Patent number: 7220308
    Abstract: To suppress a fluctuation in resistivity around a target value to thereby stably manufacture high resistivity silicon single crystals having almost the same resistivity values in a manufacturing method wherein a silicon raw material is molten to manufacture a high resistivity silicon single crystal in the range of from 100 to 2000 ? cm with a CZ method. In a case where poly-silicon produced with a Siemens method using trichlorosilane as raw material is used as the silicon raw material, an impurity concentration in the silicon raw material is selected so as to be controlled in the range of from ?5 to 50 ppta method in terms of (a donor concentration—an acceptor concentration) and the selected poly-silicon is used. In a case of a MCZ method, the poly-silicon is selected in the range of from ?25 to 20 ppta and the selected poly-silicon is used. Instead of the raw material, poly-silicon produced with a Siemens method using monosilane as raw material is used.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: May 22, 2007
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Nobumitsu Takase, Hideshi Nishikawa, Makoto Ito, Koujl Sueoka, Shinsuke Sadamitsu
  • Patent number: 7135069
    Abstract: An inexpensive method of coating silicon shot with boron atoms comprises (1) immersing silicon shot in an aqueous solution comprising a boric acid and polyvinyl alcohol, and (2) heating the solution so as to evaporate water and form a polymerized polyvinyl alcohol coating containing boron on the shot. A precise amount of this coated shot may then be mixed with a measured quantity of intrinsic silicon pellets and the resulting mixture may then be melted to provide a boron-doped silicon melt for use in growing p-type silicon bodies that can be converted to substrates for photovoltaic solar cells.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: November 14, 2006
    Assignee: Schott Solar, Inc.
    Inventor: Bernhard P. Piwczyk
  • Patent number: 7001456
    Abstract: In supplying crystalline materials in the Czochralski method, it is made use of an apparatus equipped with an inner vessel having an opening portion at the lower part or bottom thereof, which is to be charged with a granular solid material, an outer vessel containing the inner vessel therein with the function of sliding movement and thus closing the opening portion, and pull-up means for suspending the inner vessel and outer vessel in a manner causing them to ascend or descend, wherein the opening portion is opened through a sliding motion of the inner vessel or outer vessel for additional charging or recharging of the solid material into the molten material in the crucible, with the result that the molten material in the crucible can be prevented from splashing, the additional charging can be carried out in a static manner, the material cost becomes low and there is no risk of cracking due to rapid heating.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: February 21, 2006
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Katsunori Nakashima, Tatsuya Yabusame, Fumio Yamanaka
  • Patent number: 6908509
    Abstract: Additional charge of a solid raw material 13 in the shapes of granules/lumps, low in raw material cost, and with no risk of cracking, is performed into a molten raw material 14 in a crucible in a static manner without solidifying a surface of the molten raw material 14 in the crucible 3. A bottom of a cylindrical raw material vessel 10 made of a material non-meltable when being in contact with the molten raw material 14 in the crucible 3 is closed with a bottom cover 11 made of a material meltable and removable when being in contact with the molten raw material 14 in the crucible 3. The raw material vessel 10 in a state of being filled with the solid raw material 13 in the shapes of granules/lumps is hung down above the crucible 3 to immerse the lower portion thereof into the molten raw material 14 in the crucible 3.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: June 21, 2005
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Katsunori Nakashima, Makoto Ito
  • Patent number: 6896732
    Abstract: A raw material feeder apparatus for industrial crystal growth systems includes a hopper disposed within a vacuum chamber and adapted to hold a quantity of raw material therein. A slide is disposed adjacent to an opening of the hopper and configured to receive the raw material from the hopper thereon. The slide is selectively moved between an open feeding position and a closed non-feeding position. The slide and a door cooperatively close the opening of the hopper, or in their open state, control the flow of raw material from the hopper. A vibrator associated with the slide feeds the raw material from the slide into an outlet tube for conveyance of the raw material to the crystal growth system.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: May 24, 2005
    Inventors: Bryan Fickett, Robert Bushman
  • Patent number: 6840998
    Abstract: A silicon single crystal is produced by crucible-free float zone pulling, has a diameter of at least 200 mm over a length of at least 200 mm and is free of dislocations in the region of this length. A silicon wafer is separated from the silicon single crystal by a process for producing the silicon single crystal. The silicon single crystal is produced by crucible-free float zone pulling in a receptacle, in which an atmosphere of inert gas and nitrogen exerts a pressure of 1.5-2.2 bar, the atmosphere being continuously exchanged, with the volume of the receptacle being exchanged at least twice per hour. A flat coil with an external diameter of at least 220 mm is inserted in order to melt a stock ingot. The single crystal is pulled at a rate in a range from 1.4-2.2 mm/min and is periodically rotated through a sequence of rotation angles.
    Type: Grant
    Filed: July 23, 2002
    Date of Patent: January 11, 2005
    Assignee: Siltronic AG
    Inventors: Ludwig Altmannshofer, Manfred Grundner, Janis Virbulis
  • Patent number: 6805746
    Abstract: Granules/lumps poly-silicon raw material, low in raw material cost and free of the hazard of crack is additionally charged into a crucible in a safe and steady manner. In a single crystal growth according to the CZ method, poly-silicon raw material ins initially charged into a crucible. Above the initially charged poly-silicon raw material, a heat resistant tubular container is placed. The granules/lumps poly-silicon raw material for use in additional charging is charged inot the tubular container. The poly-silicon raw material initially charged into the crucible is melted. The poly-silicon raw material in the tubular container gradually and spontaneously comes down into the crucible, as the bulk of poly-silicon raw material is decreased according to the melting of the initially charged raw material.
    Type: Grant
    Filed: July 3, 2002
    Date of Patent: October 19, 2004
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Manabu Moroishi, Kenichi Takenaka
  • Patent number: 6740158
    Abstract: An inexpensive method of coating silicon shot with boron atoms comprises (1) immersing silicon shot in a boron dopant spin-on solution comprising a borosilicate, a polymer precursor, and a volatile solvent, and (2) removing the solvent so as to leave a polymeric coating containing borosilicate on the shot. A precise amount of this coated shot may then be mixed with a measured quantity of silicon pellets and the resulting mixture may then be melted to provide a boron-doped silicon melt for use in growing p-type silicon bodies that can be converted to substrates for photovoltaic solar cells.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: May 25, 2004
    Assignee: RWE Schott Solar Inc.
    Inventor: Bernhard P. Piwczyk
  • Patent number: 6702892
    Abstract: An apparatus is provided which is to be used in producing single crystals for silicon wafers useful as semiconductor materials and which can stably produce large-diameter, long-length and high-quality single crystals from which wafers limited in the number of grown-in defects can be taken. This silicon single crystal production apparatus comprises a cooling member surrounding the single crystal to be pulled up and having an internal surface coaxial with the pulling axis and thermal insulating members disposed outside the outer surface and below the bottom surface of the cooling member, the cooling member having an internal surface diameter of 1.20D to 2.50D (D being the diameter of the single crystal to be pulled up) and a length of not less than 0.25D, the distance from the melt surface to the bottom surface of the cooling member being 0.30D to 0.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: March 9, 2004
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Masahiko Okui, Manabu Nishimoto, Takayuki Kubo, Fumio Kawahigashi, Hiroshi Asano
  • Patent number: 6626993
    Abstract: A process for dendritic web growth is described. The process includes providing a melt, growing a dendritic web crystal from the melt, replenishing the melt during the step of growing the dendritic web crystal, and applying a magnetic field to the melt during the step of growing the dendritic web crystal. An apparatus for stabilizing dendritic web growth is also described. The apparatus includes a crucible including a feed compartment for receiving pellets to facilitate melt replenishment and a growth compartment designed to hold a melt for dendritic web growth. The apparatus further includes a magnetic field generator configured to provide a magnetic field during dendritic web growth.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: September 30, 2003
    Assignee: Ebara Solar, Inc.
    Inventors: Daniel L. Meier, Gregory T. Neugebauer, Edward V. Macuga, Robert P. Stoehr, Philip J. Simpson, Jalal Salami
  • Publication number: 20020129759
    Abstract: A method for producing a silicon single crystal, the method being capable of suppressing the dislocation of a single crystal. When a silicon single crystal is produced by a Czochralski method in which a horizontal magnetic field or a cusp magnetic field is applied and the single crystal during growth is dislocated, the single crystal with dislocations is dissolved in a nonmagnetic field condition and thereafter a magnetic field is applied again to pull up the silicon single crystal. The flow rate of argon gas is designed to be 100 L/min or more and the pressure in a furnace is designed to be 6700 pa or less when the single crystal with dislocations is dissolved.
    Type: Application
    Filed: December 18, 2001
    Publication date: September 19, 2002
    Inventors: Hideki Fujiwara, Manabu Nishimoto, Isamu Miyamoto, Hiroshi Morita
  • Publication number: 20020129760
    Abstract: An apparatus for pulling up a strip of semiconductor crystal continuously from a crucible with a pair of endless belts has a position control device for automatically adjusting a transverse position of the strip of semiconductor crystal. The position control device is disposed in a path for pulling up the strip of semiconductor crystal from the crucible. The position control device comprises a pair of blocks disposed one on each side of the path transversely of the strip of semiconductor crystal and movable transversely of the strip of semiconductor crystal, and a pair of position sensors mounted respectively on the blocks for detecting respective edges of the strip of semiconductor crystal. The blocks have respective side faces for adjusting a direction in which the strip of semiconductor crystal is pulled up, by contacting the respective edges of the strip of semiconductor crystal.
    Type: Application
    Filed: March 12, 2002
    Publication date: September 19, 2002
    Inventors: Kenji Terao, Hideyuki Isozaki, Yasuyoshi Yamaguchi
  • Patent number: 6423137
    Abstract: The present invention aims to prevent solidification of a melt in a feeding pipe without providing heating means such as heater or heat keeping means such as heat insulating material on outer periphery of the feeding pipe when the melt is supplied from an auxiliary crucible into a main crucible via the feeding pipe by overflow. At the center of the auxiliary crucible 1 made of quartz, a pipe 1a for feeding the melt from the auxiliary crucible 1 to the main crucible 11 by overflow is formed. When the raw material in the auxiliary crucible is melted, it is designed in such manner that the raw material is not continuously supplied to the auxiliary crucible but it is supplied in such quantity that the melt overflows intermittently into an opening on the upper end of the pipe 1a from the auxiliary crucible 1 into the main crucible 11.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: July 23, 2002
    Assignee: Silicon Crystal Research Institute Corp.
    Inventor: Nobumitsu Takase