Including Vertical Precursor-product Interface (e.g., Horizontal Bridgman) Patents (Class 117/82)
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Patent number: 12186797Abstract: A method of manufacturing a component includes forming a mould assembly including an initial mould unit, providing a seed crystal including a primary growth direction, determining an optimal angular orientation of the unit, rotating the unit to dispose the unit's optimal angular orientation, encasing the unit in a refractory material, and forming a refractory mould unit having a component mould including a mould wall defining a mould cavity, and a seed holder. In the optimal angular orientation, the seed crystal's primary growth direction is angled away from the wall, thereby forming a converging disposition with the wall in a of the wall's first region facing the central sprue and a diverging disposition with the wall in the wall's second region facing a mould heater. The method includes receiving the seed crystal within the seed holder and filling the mould cavity with molten castable material to form the component.Type: GrantFiled: May 17, 2024Date of Patent: January 7, 2025Assignee: ROLLS-ROYCE PLCInventors: Neil D'Souza, Kevin Goodwin, John D Lehane, Martin R Perry
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Patent number: 9541452Abstract: According to an embodiment, a method of forming a calibration curve is provided. The method includes ion-implanting different doses of an impurity into a plurality of first samples, measuring an intensity of photoluminescence deriving from the impurity by a photoluminescence spectroscopy for the first samples and a second sample made of the same semiconductor. Based on the amount of implanted impurity, the intensity of the photoluminescence, and a concentration of the impurity contained in the second sample measured by a method other than the photoluminescence spectroscopy, a calibration curve is formed.Type: GrantFiled: May 22, 2015Date of Patent: January 10, 2017Assignee: GlobalWafers Japan Co., Ltd.Inventors: Satoko Nakagawa, Kazuhiko Kashima
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Patent number: 9039833Abstract: The present invention relates to a method for the preparation of solar grade silicon comprising crystallization of large high purity silicon crystals in a hyper eutectic binary or ternary alloy containing silicon, or a refined silicon melt, wherein small silicon crystals are added to the melt and the resulting large silicon crystals are separated from the melt. The separation may be performed by centrifugation or filtration.Type: GrantFiled: February 25, 2010Date of Patent: May 26, 2015Inventor: Harsharn Tathgar
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Patent number: 9017477Abstract: Provided is a process for producing colloidal crystals from which a large single crystal reduced in lattice defects and unevenness can be easily produced at low cost without fail. The process for colloidal crystal production comprises: preparing a colloidal polycrystal dispersion in which colloidal crystals precipitate at a given temperature (preparation step); introducing into a vessel The colloidal polycrystal dispersion in the state of containing fine colloidal polycrystals precipitated (introduction step); and melting the colloidal polycrystals and then recrystallizing the molten polycrystals (recrystallization step). The crystals thus obtained have fewer lattice defects and less unevenness than the original polycrystals.Type: GrantFiled: April 30, 2009Date of Patent: April 28, 2015Assignees: Nagoya City University, Fuji Chemical Co., Ltd.Inventors: Junpei Yamanaka, Mariko Shinohara, Akiko Toyotama, Koki Yoshizawa, Sachiko Onda, Masakatsu Yonese, Fumio Uchida
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Patent number: 8986446Abstract: This invention provides an Si doped GaAs single crystal ingot, which has a low crystallinity value as measured in terms of etch pit density (EPD) per unit area and has good crystallinity, and a process for producing the same. An Si-doped GaAs single crystal wafer produced in a latter half part in the growth of the Si doped GaAs single crystal ingot is also provided. A GaAs compound material is synthesized in a separate synthesizing oven (a crucible). An Si dopant is inserted into the compound material to prepare a GaAs compound material with the Si dopant included therein. The position of insertion of the Si dopant is one where, when the GaAs compound material is melted, the temperature is below the average temperature. After a seed crystal is inserted into a crucible for an apparatus for single crystal growth, the GaAs compound material with the Si dopant included therein and a liquid sealing compound are introduced into the crucible.Type: GrantFiled: October 25, 2010Date of Patent: March 24, 2015Assignee: Dowa Electronics Materials Co., Ltd.Inventor: Yoshikazu Oshika
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Patent number: 8968471Abstract: The present disclosure provides an apparatus for manufacturing a silicon substrate for solar cells using continuous casting, which can improve quality, productivity and energy conversion efficiency of the silicon substrate. The apparatus includes a crucible unit configured to receive raw silicon and having a discharge port, a heating unit provided to an outer wall and an external bottom surface of the crucible unit and heating the crucible unit to form molten silicon, a casting unit casting the molten silicon into a silicon substrate, a cooling unit rapidly cooling the silicon substrate, and a transfer unit disposed at one end of the cooling unit and transferring the silicon substrate. The casting unit includes a casting unit body having a casting space defined therein to be horizontally connected to the discharge port, and an assistant heating mechanism that preheats the casting unit body to control a solidification temperature of the silicon substrate.Type: GrantFiled: May 25, 2011Date of Patent: March 3, 2015Assignee: Korea Institute of Energy ResearchInventors: Bo-Yun Jang, Jin-Seok Lee, Joon-Soo Kim
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Patent number: 8926751Abstract: The present invention relates to a gas flow guiding device for use in a crystal-growing furnace. The gas flow guiding device has an insulation layer enclosing a crucible, a gas inlet mounted in the upper insulation layer, and a gas exit formed in the lateral insulation layer. A plurality of guide plates are radially arranged around the opening of the gas inlet, so that the free surface of the melt is blown by the guided gas flow in such a manner that the gas flow takes the impurity away from the free surface efficiently. As a result, the crystal ingot obtained by solidifying the melt will exhibit a reduced concentration of impurities and an improved crystal quality.Type: GrantFiled: December 2, 2010Date of Patent: January 6, 2015Assignee: National Central UniversityInventors: Jyh-Chen Chen, Ying-Yang Teng, Chung-Wei Lu, Hsueh-I Chen
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Patent number: 8916124Abstract: When a group III nitride crystal is grown in a pressurized atmosphere of a nitrogen-containing gas from a melt 50 including at least a group III element, nitrogen and an alkali metal or an alkali earth metal, a melt-holding vessel 160 that holds the above-described melt 50 is swung about two axes different in direction from each other such as an X-axis and a Y-axis.Type: GrantFiled: November 27, 2008Date of Patent: December 23, 2014Assignee: Ricoh Company, Ltd.Inventors: Hisashi Minemoto, Osamu Yamada, Takeshi Hatakeyama, Hiroaki Hoshikawa, Yasunori Tokunou
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Patent number: 8845805Abstract: The invention relates to a device and a method for producing crystalline bodies by directional solidification. The device comprises a melting furnace (11) having a heating chamber (12) in which at least one supporting surface (13) for a crucible (8) and at least one gas purging device arranged above the supporting surface (13) and having a gas outlet facing the supporting surface (13) are defined. An embodiment of the device is characterized in that the gas outlet is defined by one or more openings in a lower plunger surface of a plunger-shaped element (2) which has a geometry adapted to the inner shape of the crucible (8), said shape allowing an at least partial insertion of the plunger-shaped body (2) into the crucible (8). The gas purging device and/or the supporting surface (13) comprise an adjusting mechanism or are designed to be adjustable in such a manner that they allow an adjustment of a perpendicular distance between the supporting surface (13) and the plunger-shaped body (2).Type: GrantFiled: February 14, 2008Date of Patent: September 30, 2014Assignee: Solarworld Industries Sachsen GmbHInventors: Christian Reimann, Jochen Friedrich, Marc Dietrich
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Patent number: 8834630Abstract: Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.Type: GrantFiled: November 6, 2012Date of Patent: September 16, 2014Assignee: Crystal IS, Inc.Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo Schowalter, Glen A. Slack
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Patent number: 8815392Abstract: A process is disclosed for producing a doped gallium arsenide single crystal by melting a gallium arsenide starting material and subsequently solidifying the gallium arsenide melt, wherein the gallium arsenide melt contains an excess of gallium relative to the stoichiometric composition, and wherein it is provided for a boron concentration of at least 5×1017 cm?3 in the melt or in the obtained crystal. The thus obtained crystal is characterized by a unique combination of low dislocation density, high conductivity and yet excellent, very low optic absorption, particularly in the range of the near infrared.Type: GrantFiled: November 8, 2012Date of Patent: August 26, 2014Assignee: Freiberger Compound Materials GmbHInventors: Ulrich Kretzer, Frank Börner, Stefan Eichler, Frieder Kropfgans
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Patent number: 8784561Abstract: Methods are disclosed for inhibiting heat transfer through lateral sidewalls of a support member positioned beneath a crucible in a directional solidification furnace. The methods include the use of insulation positioned adjacent the lateral sidewalls of the support member. The insulation inhibits heat transfer through the lateral sidewalls of the support member to ensure the one-dimensional transfer of heat from the melt through the support member.Type: GrantFiled: June 25, 2012Date of Patent: July 22, 2014Assignee: MEMC Singapore Pte. Ltd. (UEN200614794D)Inventors: Rituraj Nandan, Benjamin Michael Meyer, Lee William Ferry
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Patent number: 8784560Abstract: A method for producing a crystallized compound semiconductor material comprises synthesizing said material by fusion and inter-reaction of its constituents placed in elementary form constituting a charge into a sealed ampoule, and then crystallizing the resulting material in liquid form by cooling.Type: GrantFiled: February 16, 2011Date of Patent: July 22, 2014Assignee: Societe Francaise de Detecteurs Infrarouges-SofradirInventors: Sylvain Paltrier, Thierry Miguet
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Patent number: 8747552Abstract: Fabrication of doped AlN crystals and/or AlGaN epitaxial layers with high conductivity and mobility is accomplished by, for example, forming mixed crystals including a plurality of impurity species and electrically activating at least a portion of the crystal.Type: GrantFiled: December 18, 2009Date of Patent: June 10, 2014Assignee: Crystal IS, Inc.Inventors: Glen A. Slack, Leo J. Schowalter
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Patent number: 8709154Abstract: Methods are provided for casting one or more of a semiconductor, an oxide, and an intermetallic material. With such methods, a cast body of a monocrystalline form of the one or more of a semiconductor, an oxide, and an intermetallic material may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm.Type: GrantFiled: July 23, 2008Date of Patent: April 29, 2014Assignee: AMG IdealCast Solar CorporationInventor: Nathan G. Stoddard
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Patent number: 8709155Abstract: Scintillation materials of this invention have an alkali halide host material, a (first) scintillation dopant of various types, and a variety of second dopants (co-dopants). In another embodiment, the scintillation materials of this invention have an alkali halide host material, a (first) scintillation dopant of various types, a variety of second dopants (co-dopants), and a variety of third dopants (co-dopants). Co-dopants of this invention are capable of providing a second auxiliary luminescent cation dopant, capable of introducing an anion size and electronegativity mismatch, capable of introducing a mismatch of anion charge, or introducing a mismatch of cation charge in the host material.Type: GrantFiled: August 9, 2013Date of Patent: April 29, 2014Inventors: Charles Brecher, Vivek Nagarkar
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Patent number: 8663388Abstract: Disclosed are a single crystal wire and other single crystal articles, and a manufacturing method thereof. The method comprises the steps of: placing into a growth crucible at least one metal selected from the group consisting of gold, copper, silver, aluminum and nickel; heating and melting the metal placed in the growth crucible; growing a single crystal using metal crystal as a seed by Czochralski or Bridgman method; cutting the grown single crystal by electric discharge machining; and machining the cut single crystal and producing a wire or other articles such as a ring. In the method, the grown metal single crystal is cut into a disc-shaped piece by electric discharge machining. The piece is transformed into a single crystal wire or other articles by wire-cut electric discharge machining, and the single crystal wire can be used as a ring, a pendant, or a wire for high-quality cables for audio and video systems.Type: GrantFiled: May 6, 2009Date of Patent: March 4, 2014Assignee: Korea Electrotechnology Research InstituteInventors: Se Young Jeong, Chae Ryong Cho, Sang Eon Park, Sung Kyu Kim
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Patent number: 8657955Abstract: It is provided a melt composition for growing a gallium nitride single crystal by flux method. The melt composition contains gallium, sodium and barium, and a content of barium is 0.05 to 0.3 mol % with respect to 100 mol % of sodium.Type: GrantFiled: August 3, 2009Date of Patent: February 25, 2014Assignees: NGK Insulators, Ltd, Osaka University, Toyoda Gosei Co., Ltd.Inventors: Makoto Iwai, Takanao Shimodaira, Yoshihiko Yamamura, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki
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Patent number: 8647433Abstract: Systems and methods are disclosed for crystal growth including features of reducing micropit cavity density in grown germanium crystals. In one exemplary implementation, there is provided a method of inserting an ampoule with raw material into a furnace having a heating source, growing a crystal using a vertical growth process wherein movement of a crystallizing temperature gradient relative to the raw material/crucible is achieved to melt the raw material, and growing, at a predetermined crystal growth length, the material to achieve a monocrystalline crystal, wherein monocrystalline ingots having reduced micro-pit densities are reproducibly provided.Type: GrantFiled: December 13, 2009Date of Patent: February 11, 2014Assignee: AXT, Inc.Inventors: Weiguo Liu, Xiao Li
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Patent number: 8628614Abstract: Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of monocrystalline silicon may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm is provided.Type: GrantFiled: October 19, 2011Date of Patent: January 14, 2014Assignee: AMG IdealCast Solar CorporationInventor: Nathan G. Stoddard
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Patent number: 8597535Abstract: A ternary single crystal relaxor piezoelectric of PMN-PZ-PT grown from a novel melt using the Vertical Bridgeman method. The ternary single crystals are characterized by a Curie temperature, Tc, of at least 150° C. and a rhombohedral to tetragonal phase transition temperature, Trt, of at least about 110° C. The ternary crystals further exhibit a piezoelectric coefficient, d33, in the range of at least about 1200-2000 pC/N.Type: GrantFiled: May 16, 2011Date of Patent: December 3, 2013Assignee: TRS Technologies, Inc.Inventors: Jun Luo, Wesley Hackenberger
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Patent number: 8591649Abstract: Methods are provided for casting one or more of a semi-conductor, an oxide, and an intermetallic material. With such methods, a cast body of a geometrically ordered multi-crystalline form of the one or more of a semiconductor, an oxide, and an intermetallic material may be formed that is free or substantially free of radially-distributed impurities and defects and having at least two dimensions that are each at least about 10 cm.Type: GrantFiled: July 23, 2008Date of Patent: November 26, 2013Assignee: Advanced Metallurgical Group Idealcast Solar Corp.Inventor: Nathan G. Stoddard
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Patent number: 8591648Abstract: A crystal growing system having multiple rotatable crucibles and using a temperature gradient method comprises a crystal furnace, a plurality of crucibles, a supporting device, and a temperature control device. The crystal furnace includes a furnace body, a heater, and a hearth, wherein the furnace body from outer to inner includes an outer shell, a fiber insulation layer, an insulation brick layer, and a refractory layer. The crucible supporting device includes an elevator, a plurality of crucible guiding tubes, and a plurality of tube holders each capable of supporting a crucible guiding tube, a moving device that is connected to the elevator, a motor with electrical power that is connected to the moving device, wherein there is an affixing device between each pair of guiding tube and guiding tube holder. Each crucible is located in a corresponding crucible guiding tube. The crucible supporting device is a rotatable device.Type: GrantFiled: December 27, 2007Date of Patent: November 26, 2013Inventor: Youbao Wan
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Patent number: 8535440Abstract: The method of the invention promotes single crystal growth during fabrication of melt growth semiconductors. A growth ampoule and its tip have a semiconductor source material placed therein. The growth ampoule is placed in a first thermal environment that raises the temperature of the semiconductor source material to its liquidus temperature. The growth ampoule is then transitioned to a second thermal environment that causes the semiconductor source material in the growth ampoule's tip to attain a temperature that is below the semiconductor source material's solidus temperature. The growth ampoule so-transitioned is then mechanically perturbed to induce single crystal growth at the growth ampoule's tip.Type: GrantFiled: April 12, 2010Date of Patent: September 17, 2013Assignee: The United States of America as Represented by the Administrator of the National Aeronautics and Space AdministrationInventor: Ching-Hua Su
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Patent number: 8506706Abstract: Systems, methods, and substrates directed to growth of monocrystalline germanium (Ge) crystals are disclosed. In one exemplary implementation, there is provided a method for growing a monocrystalline germanium (Ge) crystal. Moreover, the method may include loading first raw Ge material into a crucible, loading second raw Ge material into a container for supplementing the Ge melt material, sealing the crucible and the container in an ampoule, placing the ampoule with the crucible into a crystal growth furnace, as well as melting the first and second raw Ge material and controlling the crystallizing temperature gradient of the melt to reproducibly provide monocrystalline germanium ingots with improved/desired characteristics.Type: GrantFiled: September 5, 2009Date of Patent: August 13, 2013Assignee: AXT, IncInventor: Weiguo Liu
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Patent number: 8506705Abstract: A nitride single crystal is produced on a seed crystal substrate 5 in a melt containing a flux and a raw material of the single crystal in a growing vessel 1. The melt 2 in the growing vessel 1 has temperature gradient in a horizontal direction. In growing a nitride single crystal by flux method, adhesion of inferior crystals onto the single crystal is prevented and the film thickness of the single crystal is made constant.Type: GrantFiled: September 9, 2009Date of Patent: August 13, 2013Assignee: NGK Insulators, Ltd.Inventors: Mikiya Ichimura, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Yasuo Kitaoka
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Patent number: 8475593Abstract: In a crystal preparing device, a crucible holds a mixed molten metal containing alkali metal and group III metal. A container has a container space contacting the mixed molten metal and holds a molten alkali metal between the container space and an outside of the container, the molten alkali metal contacting the container space. A gas supply device supplies nitrogen gas to the container space. A heating device heats the crucible to a crystal growth temperature. The crystal preparing device is provided so that a vapor pressure of the alkali metal which evaporates from the molten alkali metal is substantially equal to a vapor pressure of the alkali metal which evaporates from the mixed molten metal.Type: GrantFiled: June 28, 2011Date of Patent: July 2, 2013Assignee: Ricoh Company, Ltd.Inventors: Hirokazu Iwata, Seiji Sarayama, Akihiro Fuse
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Patent number: 8449672Abstract: This disclosure pertains to a process for making single crystal Group III nitride, particularly gallium nitride, at low pressure and temperature, in the region of the phase diagram of Group III nitride where Group III nitride is thermodynamically stable comprises a charge in the reaction vessel of (a) Group III nitride material as a source, (b) a barrier of solvent interposed between said source of Group III nitride and the deposition site, the solvent being prepared from the lithium nitride (Li3N) combined with barium fluoride (BaF2), or lithium nitride combined with barium fluoride and lithium fluoride (LiF) composition, heating the solvent to render it molten, dissolution of the source of GaN material in the molten solvent and following precipitation of GaN single crystals either self seeded or on the seed, maintaining conditions and then precipitating out.Type: GrantFiled: April 25, 2008Date of Patent: May 28, 2013Assignee: The United States of America as represented by the Secretary of the NavyInventors: Boris N. Feigelson, Richard L. Henry
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Publication number: 20130087711Abstract: The present disclosure discloses rare earth metal halide scintillators compositions with reduced hygroscopicity. Compositions in specific implementations include three group of elements: Lanthanides, (La, Ce, Lu, Gd or V), elements in group 17 of the periodic table of elements (CI, Br and I) and elements of group 13 (B, AI, Ga, In, TI), and any combination of these elements. Examples of methods for making the compositions are also disclosed.Type: ApplicationFiled: October 8, 2012Publication date: April 11, 2013Applicant: SIEMENS MEDICAL SOLUTIONS USA, INC.Inventor: Siemens Medical Solutions USA, Inc.
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Patent number: 8404043Abstract: A high-quality polycrystalline bulk semiconductor having a large crystal grain size is produced by the casting method in which growth is regulated so as to proceed in the same plane direction, i.e., the {110}; plane or {112} plane is disclosed. The process, which is for producing a polycrystalline bulk semiconductor, comprises: a step in which a melt of a semiconductor selected among Si, Ge, and SiGe is held in a crucible; a step in which a bottom part of the crucible is cooled to give a temperature gradient and that part of the melt which is located directly on the crucible bottom is rapidly cooled in the beginning of growth to supercool the melt around the crucible bottom; a step in which the crucible is cooled to grow nuclei on the crucible bottom due to the supercooled state of the melt around the crucible bottom and thereby grow dendritic crystals along the crucible bottom; and a step in which a polycrystalline bulk of the semiconductor is then grown on the upper side of the dendritic crystals.Type: GrantFiled: May 30, 2008Date of Patent: March 26, 2013Assignee: Tohoku UniversityInventors: Kozo Fujiwara, Kazuo Nakajima
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Patent number: 8394195Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.Type: GrantFiled: January 27, 2012Date of Patent: March 12, 2013Assignee: Siemens Medical Solutions USA, Inc.Inventors: Mark S. Andreaco, Piotr Szupryczynski, A. Andrew Carey
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Patent number: 8329295Abstract: A process is disclosed for producing a doped gallium arsenide single crystal by melting a gallium arsenide starting material and subsequently solidifying the gallium arsenide melt, wherein the gallium arsenide melt contains an excess of gallium relative to the stoichiometric composition, and wherein it is provided for a boron concentration of at least 5×1017 cm?3 in the melt or in the obtained crystal. The thus obtained crystal is characterized by a unique combination of low dislocation density, high conductivity and yet excellent, very low optic absorption, particularly in the range of the near infrared.Type: GrantFiled: July 9, 2009Date of Patent: December 11, 2012Assignee: Freiberger Compound Materials GmbHInventors: Ulrich Kretzer, Frank Börner, Stefan Eichler, Frieder Kropfgans
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Patent number: 8323406Abstract: Bulk single crystal of aluminum nitride (AlN) having an a real planar defect density?100 cm?2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.Type: GrantFiled: January 17, 2008Date of Patent: December 4, 2012Assignee: Crystal IS, Inc.Inventors: Robert T. Bondokov, Kenneth E. Morgan, Leo J. Schowalter, Glen A. Slack
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Patent number: 8317920Abstract: A directional solidification furnace includes a crucible for holding molten silicon and a lid covering the crucible and forming an enclosure over the molten silicon. The crucible also includes an inlet in the lid for introducing inert gas above the molten silicon to inhibit contamination of the molten silicon.Type: GrantFiled: September 19, 2009Date of Patent: November 27, 2012Assignee: MEMC Singapore Pte. Ltd.Inventors: Steven L. Kimbel, Jihong (John) Chen, Richard G. Schrenker, Lee W. Ferry
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Patent number: 8293010Abstract: A method of forming a templated casting involves incorporating a liquid feedstock into the channels of a honeycomb substrate to form a feedstock-laden substrate, and directionally solidifying the liquid feedstock within the channels.Type: GrantFiled: February 26, 2009Date of Patent: October 23, 2012Assignee: Corning IncorporatedInventors: Prantik Mazumder, Frederick Ernest Noll, John Forrest Wight, Jr.
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Patent number: 8231727Abstract: Systems and methods are disclosed for crystal growth using VGF and VB growth processes to reduce body lineage. In one exemplary embodiment, there is provided a method of inserting an ampoule with raw material into a furnace having a heating source, growing a crystal using a vertical gradient freeze process wherein the crystallizing temperature gradient is moved relative to the crystal and/or furnace to melt the raw material and reform it as a monocrystalline compound, and growing the crystal using a vertical Bridgman process on the wherein the ampoule/heating source are moved relative each other to continue to melt the raw material and reform it as a monocrystalline compound.Type: GrantFiled: April 17, 2008Date of Patent: July 31, 2012Assignee: AXT, Inc.Inventors: Weiguo Liu, A. Grant Elliot
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Patent number: 8231729Abstract: It is disclosed an apparatus for growing a nitride single crystal using a flux containing an easily oxidizable substance. The apparatus has a crucible for storing the flux; a pressure vessel for storing the crucible and charging an atmosphere containing at least nitrogen gas; furnace materials disposed within the pressure vessel and out of the crucible; heaters attached to the furnace material; and alkali-resistant and heat-resistant metallic layers covering the furnace material.Type: GrantFiled: August 15, 2008Date of Patent: July 31, 2012Assignees: NGK Insulators, Ltd., Osaka University, Toyoda Gosei Co., Ltd.Inventors: Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki
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Patent number: 8210906Abstract: A wafer slicing method includes winding a wire around rollers and pressing the wire against an ingot while supplying slurry to the rollers. A previously conducted experiment provides a supply temperature profile of the slurry during the slicing process and the relationship to the axial displacement of the rollers. This relationship is used to implement slurry delivery during the slicing process. The resultant wafers are bowed in a uniform direction. This slicing method provides excellent reproducibility in addition to producing wafers that are bowed in a uniform direction.Type: GrantFiled: August 22, 2007Date of Patent: July 3, 2012Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Hiroshi Oishi, Daisuke Nakamata
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Patent number: 8211228Abstract: 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: GrantFiled: October 21, 2005Date of Patent: July 3, 2012Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Ryoji Hoshi, Takahiro Yanagimachi
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Patent number: 8133319Abstract: A Periodic Table Group 13 metal nitride crystal is grown by causing a reaction of a Periodic Table Group 13 metal phase with a nitride-containing molten salt phase to proceed while removing a by-product containing a metal element except for Periodic Table Group 13 metals, from the reaction field. According to this process, a high-quality Periodic Table Group 13 metal nitride bulk crystal can be produced under low pressure or atmospheric pressure.Type: GrantFiled: July 4, 2005Date of Patent: March 13, 2012Assignee: Mitsubishi Chemical CorporationInventors: Yoji Arita, Yoshinori Seki, Takeshi Tahara, Yuzuru Sato
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Publication number: 20120048083Abstract: A method for producing growth-axis oriented single crystal sapphire cores or near-net cores is provided. According to the method, a boule is grown on a desired growth axis having a first axial end and a second axial end. An orientation of a plane normal to the desired growth axis with respect to the boule is determined. The boule is then cored in a direction perpendicular to the plane to produce at least one growth-axis oriented single crystal sapphire core, or the boule is outer-diameter-grinded the boule to form a single crystal sapphire near-net core.Type: ApplicationFiled: September 1, 2011Publication date: March 1, 2012Applicant: ADVANCED RENEWABLE ENERGY COMPANY LLCInventors: Carl Richard Schwerdtfeger, Matthew Gary Klotz, Chandra P. Khattak
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Patent number: 8123857Abstract: A method for producing a p-type SiC semiconductor single crystal, including: using a solution in which C is dissolved in a Si melt and 30 to 70 at. % Cr and 0.1 to 20 at. % Al, based on a total weight of the Si melt, Cr, and Al, are added to the Si melt, to grow a p-type SiC semiconductor single crystal on a SiC single crystal substrate from the solution.Type: GrantFiled: February 5, 2009Date of Patent: February 28, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Yukio Terashima, Yasuyuki Fujiwara
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Patent number: 8118933Abstract: Silicon raw material is filled into a graphite crucible (10), the graphite crucible (10) is heated to form molten silicon (M), at least one rare earth element and at least one of Sn, Al, and Ge are added to molten silicon (M), and a temperature gradient is maintained in the molten silicon in which the temperature decreases from within the molten silicon toward the surface while growing an silicon carbide single crystal starting from an silicon carbide seed crystal (14) held immediately below the surface of the molten liquid.Type: GrantFiled: April 5, 2007Date of Patent: February 21, 2012Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hidemitsu Sakamoto, Yukio Terashima
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Patent number: 8101020Abstract: A crystal growth apparatus comprises a reaction vessel holding a melt mixture containing an alkali metal and a group III metal, a gas supplying apparatus supplying a nitrogen source gas to a vessel space exposed to the melt mixture inside the reaction vessel, a heating unit heating the melt mixture to a crystal growth temperature, and a support unit supporting a seed crystal of a group III nitride crystal inside the melt mixture.Type: GrantFiled: October 13, 2006Date of Patent: January 24, 2012Assignee: Ricoh Company, Ltd.Inventors: Seiji Sarayama, Hirokazu Iwata, Akihiro Fuse
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Patent number: 8062419Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.Type: GrantFiled: December 14, 2010Date of Patent: November 22, 2011Assignee: Siemens Medical Solutions USA, Inc.Inventors: Mark S. Andreaco, Piotr Szupryczynski, A. Andrew Carey
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Patent number: 8025728Abstract: A seed crystal is immersed in a melt containing a flux and a single crystal material in a growth vessel to produce a nitride single crystal on the seed crystal. A difference (TS-TB) of temperatures at a gas-liquid interface of the melt (TS) and at the lowermost part of the melt (TB) is set to 1° C. or larger and 8° C. or lower. Preferably, the substrate of seed crystal is vertically placed.Type: GrantFiled: September 22, 2008Date of Patent: September 27, 2011Assignees: NGK Insulators, Ltd., Osaka UniversityInventors: Mikiya Ichimura, Katsuhiro Imai, Chikashi Ihara, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
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Patent number: 8012256Abstract: Disclosed are a method of fabricating a quasi-substrate wafer with a subcarrier wafer and a growth layer, and a semiconductor body fabricated using such a quasi-substrate wafer. In the method of fabricating a quasi-substrate wafer, a growth substrate water is fabricated that is provided with a separation zone and comprises the desired material of the growth layer. The growth substrate wafer is provided with a stress that counteracts a stress generated by the formation of the separation zone, and/or the stress generated by the formation of the separation zone is distributed, by structuring a first main race of the growth substrate water and/or the separation zone, to a plurality of subregions along the first main face. The growth substrate wafer with separation zone exhibits no or only slight bowing.Type: GrantFiled: January 30, 2007Date of Patent: September 6, 2011Assignee: Osram Opto Semiconductor GmbHInventors: Georg Brüderl, Christoph Eichler, Uwe Strauss
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Patent number: 7998272Abstract: A method of fabricating a plurality of freestanding GaN wafers includes mounting a GaN substrate in a reactor, forming a GaN crystal growth layer on the GaN substrate through crystal growth, performing surface processing of the GaN crystal growth layer to form a GaN porous layer having a predetermined thickness on the GaN crystal growth layer, repeating the forming of the GaN crystal growth layer and the forming of the GaN porous layer a plurality of times to form a stack of alternating GaN crystal growth layers and GaN porous layers on the GaN substrate, and cooling the stack such that the GaN layers self-separate to form the freestanding GaN wafers. The entire process of forming a GaN porous layer and a thick GaN layer is performed in-situ in a single reactor. The method is very simplified compared to the prior art. In this way, the entire process is performed in one chamber, and in particular, GaN surface processing and growth proceed using an HVPE process gas such that costs are greatly reduced.Type: GrantFiled: November 14, 2006Date of Patent: August 16, 2011Assignee: Samsung Corning Precision Materials, Co., Ltd.Inventor: In-Jae Song
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Patent number: 7918936Abstract: To reduce the heat input to the bottom of the crucible and to control heat extraction independently of heat input, a shield can be raised between a heating element and a crucible at a controlled speed as the crystal grows. Other steps could include moving the crucible, but this process can avoid having to move the crucible. A temperature gradient is produced by shielding only a portion of the heating element; for example, the bottom portion of a cylindrical element can be shielded to cause heat transfer to be less in the bottom of the crucible than at the top, thereby causing a stabilizing temperature gradient in the crucible.Type: GrantFiled: October 19, 2007Date of Patent: April 5, 2011Assignee: GT Crystal Systems, LLCInventors: Frederick Schmid, Chandra P. Khattak, David B. Joyce
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Patent number: 7842133Abstract: In a method of growing a single crystal by melting a raw material within a vessel under a nitrogenous and non-oxidizing atmosphere, the vessel is oscillated and the melted raw material is contacted with an agitation medium made of a solid unreactive with the melted raw material.Type: GrantFiled: August 12, 2008Date of Patent: November 30, 2010Assignees: NGK Insulators, Ltd., Osaka University, Toyoda Gosei Co., Ltd.Inventors: Makoto Iwai, Takanao Shimodaira, Shuhei Higashihara, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki, Koji Hirata