Carbide Containing (e.g., Sic) {c30b 29/36} Patents (Class 117/951)
  • Patent number: 10211066
    Abstract: A silicon single crystal is pulled up such that nitrogen concentration of the crystal is 1×1011 to 2×1013 atoms/cm3, the crystal cooling rate is about 4.2° C./min at a temperature of a silicon melting point to 1350° C. and is about 3.1° C./min at a temperature of 1200° C. to 1000° C., and oxygen concentration of a wafer is 9.5×1017 to 13.5×1017 atoms/cm3. After a heat treatment is performed on the wafer sliced from the silicon single crystal in a treatment condition of 875° C. for about 30 min, growth of an epitaxial layer is caused. Thus, an epitaxial wafer in which the number of epitaxial defects is not increased while maintaining predetermined oxygen concentration and slips do not occur is produced.
    Type: Grant
    Filed: April 21, 2016
    Date of Patent: February 19, 2019
    Assignee: SUMCO CORPORATION
    Inventor: Tomokazu Katano
  • Patent number: 9797064
    Abstract: A method of forming an SiC crystal including placing in an insulated graphite container a seed crystal of SiC, and supporting the seed crystal on a shelf, wherein cushion rings contact the seed crystal on a periphery of top and bottom surfaces of the seed crystal, and where the graphite container does not contact a side surface of the seed crystal; placing a source of Si and C atoms in the insulated graphite container, where the source of Si and C atoms is for transport to the seed crystal to grow the SiC crystal; placing the graphite container in a furnace; heating the furnace; evacuating the furnace; filling the furnace with an inert gas; and maintaining the furnace to support crystal growth to thereby form the SiC crystal.
    Type: Grant
    Filed: October 18, 2013
    Date of Patent: October 24, 2017
    Assignee: DOW CORNING CORPORATION
    Inventors: Mark Loboda, Roman Drachev, Darren Hansen, Edward Sanchez
  • Patent number: 9011598
    Abstract: The present invention provides methods for fabricating a composite substrate including a supporting substrate and a layer of a binary or ternary material having a crystal form that is non-cubic and semi-polar or non-polar. The methods comprise transferring the layer of a binary or ternary material from a donor substrate to a receiving substrate.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: April 21, 2015
    Assignee: Soitec
    Inventors: Alice Boussagol, Frédéric Dupont, Bruce Faure
  • Patent number: 8980003
    Abstract: In a method of manufacturing a silicon carbide single crystal, a silicon carbide substrate having a surface of one of a (11-2n) plane and a (1-10n) plane, where n is any integer number greater than or equal to 0, is prepared. An epitaxial layer having a predetermined impurity concentration is grown on the one of the (11-2n) plane and the (1-10n) plane of the silicon carbide substrate by a chemical vapor deposition method so that a threading dislocation is discharged from a side surface of the epitaxial layer. A silicon carbide single crystal is grown into a bulk shape by a sublimation method on the one of the (11-2n) plane and the (1-10n) plane of the epitaxial layer from which the threading dislocation is discharged.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: March 17, 2015
    Assignee: DENSO CORPORATION
    Inventors: Hiroki Watanabe, Yasuo Kitou, Masami Naito
  • Patent number: 8927396
    Abstract: An object of the present invention is to provide a production process of an epitaxial silicon carbide single crystal substrate having a high-quality silicon carbide single crystal thin film reduced in the surface defect and the like on a silicon carbide single crystal substrate with a small off-angle. According to the present invention, in the production process of an epitaxial silicon carbide single crystal substrate having a high-quality silicon carbide single crystal thin film reduced in the surface defect and the like on a silicon carbide single crystal substrate with an off-angle of 4° or less, pretreatment etching to a depth of 0.1 to 1 ?m is performed at a temperature of 1,550 to 1,650° C. by flowing a gas containing silicon and chlorine together with a hydrogen gas such that the silicon atom concentration becomes from 0.0001 to 0.01% based on hydrogen atoms in the hydrogen gas, and thereafter, an epitaxial layer is formed.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: January 6, 2015
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Takashi Aigo, Hiroshi Tsuge, Masakazu Katsuno, Tatsuo Fujimoto, Hirokatsu Yashiro
  • Patent number: 8916451
    Abstract: A method for wafer transfer includes forming a spreading layer, including graphene, on a single crystalline SiC substrate. A semiconductor layer including one or more layers is formed on and is lattice matched to the crystalline SiC layer. The semiconductor layer is transferred to a handle substrate, and the spreading layer is split to remove the single crystalline SiC substrate.
    Type: Grant
    Filed: February 5, 2013
    Date of Patent: December 23, 2014
    Assignee: International Business Machines Corporation
    Inventors: Can Bayram, Jack O. Chu, Christos Dimitrakopoulos, Jeehwan Kim, Hongsik Park, Devendra K. Sadana
  • Patent number: 8906487
    Abstract: In a base material with a single-crystal silicon carbide film according to an embodiment of the invention, a plurality of recessed portions is formed on the surface of a silicon substrate, an insulating film including silicon oxide is formed across the surface of the silicon substrate including the inner surfaces of the recessed portions, the top surfaces of side wall portions of recessed portions of the insulating film form flat surfaces, a single-crystal silicon carbide film is joined on the flat surfaces, and the recessed portions below the single-crystal silicon carbide film form holes.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: December 9, 2014
    Assignee: Seiko Epson Corporation
    Inventor: Hiroyuki Shimada
  • Patent number: 8865324
    Abstract: A method is used to produce a bulk SiC single crystal. A seed crystal is arranged in a crystal growth region of a growing crucible. An SiC growth gas phase is produced in the crystal growth region. The bulk SiC single crystal having a central longitudinal mid-axis grows by deposition from the SiC growth gas phase, the deposition taking place on a growth interface of the growing bulk SiC single crystal. The SiC growth gas phase is at least partially fed from an SiC source material and contains at least one dopant from the group of nitrogen, aluminum, vanadium and boron. At least in a central main growth region of the growth interface arranged about the longitudinal mid-axis, a lateral temperature gradient of at most 2 K/cm measured perpendicular to the longitudinal mid-axis is adjusted and maintained in this range. The bulk SiC single crystal has a large facet region.
    Type: Grant
    Filed: August 9, 2010
    Date of Patent: October 21, 2014
    Assignee: Sicrystal AG
    Inventors: Thomas Straubinger, Michael Vogel, Andreas Wohlfart
  • Patent number: 8858709
    Abstract: A physical vapor deposition method of growing a crystal includes providing a seed crystal and a source material in spaced relation inside of a growth crucible that is at least in-part gas permeable to an unwanted gas. The growth chamber is heated whereupon the source material sublimates and is transported via a temperature gradient in the growth chamber to the seed crystal where the sublimated source material precipitates. Concurrent with heating the growth chamber, a purging gas is caused to flow inside or outside of the growth crucible in a manner whereupon the unwanted gas flows from the inside to the outside of the growth crucible via the gas permeable part thereof.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: October 14, 2014
    Assignee: II-VI Incorporated
    Inventors: Ilya Zwieback, Avinash K. Gupta
  • Patent number: 8860040
    Abstract: 4H SiC epiwafers with thickness of 50-100 ?m are grown on 4° off-axis substrates. Surface morphological defect density in the range of 2-6 cm?2 is obtained from inspection of the epiwafers. Consistent carrier lifetime in the range of 2-3 ?s has been obtained on these epiwafers. Very low BPD density has been confirmed in the epiwafers with BPD density down to below 10 cm?2. Epitaxial wafers with thickness of 50-100 ?m have been used to fabricate diodes. High voltage testing has demonstrated blocking voltages near the theoretical values for 4H-SiC. Blocking voltage as high as 8 kV has been achieved in devices fabricated on 50 ?m thick epitaxial films, and blocking voltage as high as 10 kV has been obtained in devices fabricated on 80 ?m thick films. Failure analysis confirmed triangle defects, which form from surface damage or particles present during epitaxy, are killer defects and cause the device to fail in reverse bias operation.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: October 14, 2014
    Assignee: Dow Corning Corporation
    Inventors: Mark Loboda, Gilyong Chung
  • Patent number: 8853710
    Abstract: An optically active material is used to create power devices and circuits having significant performance advantages over conventional methods for affecting optical control of power electronics devices and circuits. A silicon-carbide optically active material is formed by compensating shallow donors with the boron related D-center. The resulting material can be n-type or p-type but it is distinguished from other materials by the ability to induce persistent photoconductivity in it when illuminated by electromagnetic radiation with a photon energy in excess of the threshold energy required to photoexcite electrons from the D-center to allowed states close to the conduction band edge, which varies from polytype to polytype.
    Type: Grant
    Filed: June 3, 2013
    Date of Patent: October 7, 2014
    Assignee: Power Integrations, Inc.
    Inventor: Michael S. Mazzola
  • Patent number: 8795624
    Abstract: Provided is a monocrystalline silicon carbide ingot containing a dopant element, wherein a maximum concentration of the dopant element is less than 5×1017 atoms/cm3 and the maximum concentration is 50 times or less than that of a minimum concentration of the dopant element. Also provided is a monocrystalline silicon carbide wafer made by cutting and polishing the monocrystalline silicon carbide ingot, wherein a electric resistivity at room temperature of the wafer is 5×103 ?cm or more. Further provided is a method for manufacturing the monocrystalline silicon carbide including growing the monocrystalline silicon carbide on a seed crystal from a sublimation material by a sublimation method. The sublimation material includes a solid material containing a dopant element, and the specific surface of the solid material containing the dopant element is 0.5 m2/g or less.
    Type: Grant
    Filed: October 5, 2005
    Date of Patent: August 5, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Masashi Nakabayashi, Tatsuo Fujimoto, Mitsuru Sawamura, Noboru Ohtani
  • Patent number: 8747982
    Abstract: A method is used for producing an SiC volume monocrystal by sublimation growth. Before the beginning of growth, an SiC seed crystal is arranged in a crystal growth region of a growth crucible and powdery SiC source material is introduced into an SiC storage region of the growth crucible. During the growth, by sublimation of the powdery SiC source material and by transport of the sublimated gaseous components into the crystal growth region, an SiC growth gas phase is produced there. The SiC volume monocrystal having a central center longitudinal axis grows by deposition from the SiC growth gas phase on the SiC seed crystal. The SiC seed crystal is heated substantially without bending during a heating phase before the beginning of growth, so that an SiC crystal structure with a substantially homogeneous course of lattice planes is provided in the SiC seed crystal.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: June 10, 2014
    Assignee: SiCrystal Aktiengesellschaft
    Inventors: Thomas Straubinger, Michael Vogel, Andreas Wohlfart
  • Patent number: 8685163
    Abstract: A method for growing a silicon carbide single crystal on a single crystal substrate comprising the steps of heating silicon in a graphite crucible to form a melt, bringing a silicon carbide single crystal substrate into contact with the melt, and depositing and growing a silicon carbide single crystal from the melt, wherein the melt comprises 30 to 70 percent by atom, based on the total atoms of the melt, of chromium and 1 to 25 percent by atom, based on the total atoms of the melt, of X, where X is at least one selected from the group consisting of nickel and cobalt, and carbon. It is possible to improve morphology of a surface of the crystal growth layer obtained by a solution method.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: April 1, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yukio Terashima, Yasuyuki Fujiwara
  • Patent number: 8652255
    Abstract: A method of: flowing a silicon source gas, a carbon source gas, and a carrier gas into a growth chamber under growth conditions to epitaxial grow silicon carbide on a wafer in the growth chamber; stopping or reducing the flow of the silicon source gas to interrupt the silicon carbide growth and maintaining the flow of the carrier gas while maintaining an elevated temperature in the growth chamber for a period of time; and resuming the flow of the silicon source gas to reinitiate silicon carbide growth. The wafer remains in the growth chamber throughout the method.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: February 18, 2014
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Robert E Stahlbush, Brenda L VanMil, Kok-Keong Lew, Rachael L Myers-Ward, David Kurt Gaskill, Charles R. Eddy, Jr.
  • Patent number: 8585821
    Abstract: In one embodiment of the present invention, a monocrystal SiC epitaxial substrate is produced which includes a monocrystal SiC substrate; a buffer layer made of a first SiC epitaxial film formed on the monocrystal SiC substrate; and an active layer made of a second SiC epitaxial film formed on the buffer layer. The buffer layer is grown by heat-treating a set of the monocrystal SiC substrate, a carbon source plate, and a metal Si melt layer having a predetermined thickness and interposed between the monocrystal SiC substrate and the metal Si melt layer, so as to epitaxially grow monocrystal SiC on the monocrystal SiC substrate. The active layer is grown by epitaxially growing monocrystal SiC on the buffer layer by vapor phase growth method. This allows for production of a monocrystal SiC epitaxial substrate including a high-quality monocrystal SiC active layer being low in defects.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: November 19, 2013
    Assignees: Ecotron Co., Ltd., Research Institute of Innovative Technology for the Earth
    Inventors: Nobuhiko Nakamura, Toru Matsunami, Kimito Nishikawa
  • Patent number: 8529698
    Abstract: Methods, devices, and compositions of matter related to high efficiency InGaN-based photovoltaic devices. The disclosed synthesis of semiconductor heterostructures may be exploited to produce higher efficiency, longer lasting, photovoltaic cells.
    Type: Grant
    Filed: November 11, 2009
    Date of Patent: September 10, 2013
    Assignee: Arizona Board Of Regents For And On Behalf Of Arizona State University
    Inventors: Fernando A. Ponce, Rafael Garcia
  • Patent number: 8491719
    Abstract: The present invention provides a high resistivity, high quality, large size SiC single crystal, SiC single crystal wafer, and method of production of the same, that is, a silicon carbide single crystal containing uncompensated impurities in an atomic number density of 1×1015/cm3 or more and containing vanadium in an amount less than said uncompensated impurity concentration, silicon carbide single crystal wafer obtained by processing and polishing the silicon carbide single crystal and having an electrical resistivity at room temperature of 5×103 ?cm or more, and a method of production of a silicon carbide single crystal.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: July 23, 2013
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Masashi Nakabayashi, Tatsuo Fujimoto, Mitsuru Sawamura, Noboru Ohtani
  • Patent number: 8410488
    Abstract: Micropipe-free, single crystal, silicon carbide (SiC) and related methods of manufacture are disclosed. The SiC is grown by placing a source material and seed material on a seed holder in a reaction crucible of the sublimation system, wherein constituent components of the sublimation system including the source material, reaction crucible, and seed holder are substantially free from unintentional impurities. By controlling growth temperature, growth pressure, SiC sublimation flux and composition, and a temperature gradient between the source material and the seed material or the SiC crystal growing on the seed material during the PVT process, micropipe-inducing process instabilities are eliminated and micropipe-free SiC crystal is grown on the seed material.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: April 2, 2013
    Assignee: Cree, Inc.
    Inventors: Cem Basceri, Yuri Khlebnikov, Igor Khlebnikov, Cengiz Balkas, Murat N. Silan, Hudson McD. Hobgood, Calvin H. Carter, Jr., Vijay Balakrishna, Robert T. Leonard, Adrian R. Powell, Valeri T. Tsvetkov, Jason R. Jenny
  • Patent number: 8388752
    Abstract: A method capable of stably manufacturing a SiC single crystal in the form of a thin film or a bulk crystal having a low carrier density of at most 5×1017/cm3 and preferably less than 1×1017/cm3 and which is suitable for use in various devices by liquid phase growth using a SiC solution in which the solvent is a melt of a Si alloy employs a Si alloy having a composition which is expressed by SixCryTiz wherein x, y, and z (each in atomic percent) satisfy 0.50<x<0.68, 0.08<y<0.35, and 0.08<z<0.35, or ??(1) 0.40<x?0.50, 0.15<y<0.40, and 0.15<z<0.35.??(2) x, y, and z preferably satisfy 0.53<x<0.65, 0.1<y<0.3, and 0.1<z<0.3.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: March 5, 2013
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Kazuhito Kamei, Kazuhiko Kusunoki, Nobuyoshi Yashiro, Akihiro Yauchi, Shinji Shimosaki
  • Patent number: 8257494
    Abstract: One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: September 4, 2012
    Assignee: Dimerond Technologies, LLC
    Inventor: Dieter M. Gruen
  • Patent number: 8246743
    Abstract: Single-crystal silicon carbide nanowires and a method for producing the nanowires are provided. The single-crystal silicon carbide nanowires have a very high aspect ratio and can be used for the fabrication of nanoelectronic devices, including electron gun emitters and MEMS probe tips, for use in a variety of displays and analyzers. Further provided is a filter comprising the nanowires. The filter is applied to systems for filtering vehicle engine exhaust gases to achieve improved filtering performance and increased lifetime.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: August 21, 2012
    Assignee: IUCF-HYU (Industry-University Cooperation Foundation Hanyang University)
    Inventors: Sung-Churl Choi, Sang-Hoon Lee, Jin-Seok Lee, Yun-Ki Byeun
  • Patent number: 8216366
    Abstract: A cubic silicon carbide single crystal thin film is manufactured by a method. A sacrificial layer is formed on a surface of a substrate. A cubic semiconductor layer is formed on the sacrificial layer, the cubic semiconductor layer having at least a surface of cubic crystal structure. A cubic silicon carbide single crystal layer is formed on the cubic semiconductor layer. The sacrificial layer is etched away to release a multilayer structure of the cubic semiconductor layer and the 3C—SiC layer from the substrate. A cubic silicon carbide single crystal thin film of a multilayer structure includes an AlxGa1-xAs (0.6>x?0) layer and a cubic silicon carbide single crystal layer. A metal layer is formed on a substrate. The multilayer structure is bonded to the metal layer with the AlxGa1-xAs (0.6>x?0) in direct contact with the metal layer.
    Type: Grant
    Filed: April 27, 2010
    Date of Patent: July 10, 2012
    Assignee: Oki Data Corporation
    Inventors: Mitsuhiko Ogihara, Masaaki Sakuta
  • Patent number: 8193537
    Abstract: An optically active material is used to create power devices and circuits having significant performance advantages over conventional methods for affecting optical control of power electronics devices and circuits. A silicon-carbide optically active material is formed by compensating shallow donors with the boron related D-center. The resulting material can be n-type or p-type but it is distinguished from other materials by the ability to induce persistent photoconductivity in it when illuminated by electromagnetic radiation with a photon energy in excess of the threshold energy required to photoexcite electrons from the D-center to allowed states close to the conduction band edge, which varies from polytype to polytype.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: June 5, 2012
    Assignee: SS SC IP, LLC
    Inventor: Michael S. Mazzola
  • Patent number: 8159037
    Abstract: Provided are a stack structure including an epitaxial graphene, a method of forming the stack structure, and an electronic device including the stack structure. The stack structure includes: a Si substrate; an under layer formed on the Si substrate; and at least one epitaxial graphene layer formed on the under layer.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: April 17, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yun-sung Woo, Sun-ae Seo, Dong-chul Kim, Hyun-jong Chung, Dae-young Jeon
  • Patent number: 8147991
    Abstract: A method is disclosed for producing a high quality bulk single crystal of silicon carbide in a seeded growth system by reducing the separation between a silicon carbide seed crystal and a seed holder until the conductive heat transfer between the seed crystal and the seed holder dominates the radiative heat transfer between the seed crystal and the seed holder over substantially the entire seed crystal surface that is adjacent the seed holder.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: April 3, 2012
    Assignee: Cree, Inc.
    Inventors: Jason Ronald Jenny, David Phillip Malta, Hudson McDonald Hobgood, Stephan Georg Mueller, Mark Brady, Robert Tyler Leonard, Adrian Powell, Valeri F. Tsvetkov
  • Patent number: 8118933
    Abstract: 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: Grant
    Filed: April 5, 2007
    Date of Patent: February 21, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hidemitsu Sakamoto, Yukio Terashima
  • Patent number: 7993453
    Abstract: A method for the production of an SiC single crystal includes the steps of growing a first SiC single crystal in a first direction of growth on a first seed crystal formed of an SiC single crystal, disposing the first SiC single crystal grown on the first seed crystal in a direction parallel or oblique to the first direction of growth and cutting the disposed first SiC single crystal in a direction of a major axis in a cross section perpendicular to the first direction of growth to obtain a second seed crystal, using the second seed crystal to grow thereon in a second direction of growth a second SiC single crystal to a thickness greater than a length of the major axis in the cross section, disposing the second SiC single crystal grown on the second seed crystal in a direction parallel or oblique to the second direction of growth and cutting the disposed second SiC single crystal in a direction of a major axis in a cross section perpendicular to the second direction of growth to obtain a third seed crystal, u
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: August 9, 2011
    Assignee: Showa Denko K.K.
    Inventors: Naoki Oyanagi, Tomohiro Syounai, Yasuyuki Sakaguchi
  • Patent number: 7972704
    Abstract: The present invention provides a single-crystal silicon carbide ingot capable of providing a good-quality substrate low in dislocation defects, and a substrate and epitaxial wafer obtained therefrom. It is a single-crystal silicon carbide ingot comprising single-crystal silicon carbide which contains donor-type impurity at a concentration of 2×1018 cm?3 to 6×1020 cm?3 and acceptor-type impurity at a concentration of 1×1018 cm?3 to 5.99×1020 cm?3 and wherein the concentration of the donor-type impurity is greater than the concentration of the acceptor-type impurity and the difference is 1×1018 cm?3 to 5.99×1020 cm?3, and a substrate and epitaxial wafer obtained therefrom.
    Type: Grant
    Filed: January 14, 2009
    Date of Patent: July 5, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Noboru Ohtani, Masakazu Katsuno, Hiroshi Tsuge, Masashi Nakabayashi, Tatsuo Fujimoto
  • Patent number: 7918937
    Abstract: A method of producing an epitaxial layer on a substrate of silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a thickness uniformity that is better than 5% at a growth rate which is at least 100 ?m/hour. The method comprises providing a cavity with a source material and a substrate of monolithic silicon carbide, evacuating the cavity and raising the temperature to 1400° C. Then the temperature is increased at a rate of about 20° C./min until a predetermined growth temperature is reached. Thereafter, the temperature is kept such that a predetermined growth rate between 10 ?m/min and 300 ?m/min is obtained.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: April 5, 2011
    Assignee: EL-Seed Corp.
    Inventors: Mikael Syväjärvi, Rositsa Yakimova
  • Patent number: 7913417
    Abstract: A system and method of controlling energy that is input to a material substance, for the controlled removal of moisture from the material substance, is disclosed. A controlled air flow is blown onto the material substance at a specified air flow rate over at least one specified time period such that the material substance absorbs thermal energy from the controlled air flow via at least one outer surface of the material substance. The controlled air flow is of a specified humidity level at a specified temperature level. The material substance is also irradiated with microwave energy at a first specified power level for at least a first specified time duration such that the material substance absorbs at least a part of the microwave energy and converts the absorbed microwave energy to thermal energy within the material substance. As a result, moisture is removed from the material substance in a controlled manner.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: March 29, 2011
    Assignee: The Sherwin-Williams Company
    Inventors: John J. Patka, Sr., Sharon L. Judge
  • Patent number: 7879150
    Abstract: A silicon carbide manufacturing device includes a graphite crucible, in which a seed crystal is disposed, a gas-inducing pipe coupled with the graphite crucible, and an attachment prevention apparatus. The gas-inducing pipe has a column-shaped hollow part, through which a source gas flows into the graphite crucible. The attachment prevention apparatus includes a rod extending to a flow direction of the source gas, and a revolving and rotating element for revolving the rod along an inner wall of the gas-inducing pipe while rotating the rod on an axis of the rod in parallel to the flow direction.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: February 1, 2011
    Assignee: DENSO CORPORATION
    Inventors: Masao Nagakubo, Fusao Hirose, Yasuo Kitoh
  • Patent number: 7842134
    Abstract: The invention relates to a method of manufacture of a substrate for fabrication of semiconductor layers or devices, comprising the steps of providing a wafer of silicon including at least one first surface suitable for use as a substrate for CVD diamond synthesis, growing a layer of CVD diamond of predetermined thickness and having a growth face onto the first surface of the silicon wafer, reducing the thickness of the silicon wafer to a predetermined level, and providing a second surface on the silicon wafer that is suitable for further synthesis of at least one semiconductor layer suitable for use in electronic devices or synthesis of electronic devices on the second surface itself and to a substrate suitable for GaN device growth consisting of a CVD diamond layer intimately attached to a silicon surface.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: November 30, 2010
    Inventors: Andrew John Whitehead, Christopher John Howard Wort, Geoffrey Alan Scarsbrook
  • Patent number: 7794842
    Abstract: The present invention provides a high resistivity, high quality, large size SiC single crystal, SiC single crystal wafer, and method of production of the same, that is, a silicon carbide single crystal containing uncompensated impurities in an atomic number density of 1 ×1015/cm3 or more and containing vanadium in an amount less than said uncompensated impurity concentration, silicon carbide single crystal wafer obtained by processing and polishing the silicon carbide single crystal and having an electrical resistivity at room temperature of 5×103 ?cm or more, and a method of production of a silicon carbide single crystal.
    Type: Grant
    Filed: December 27, 2004
    Date of Patent: September 14, 2010
    Assignee: Nippon Steel Corporation
    Inventors: Masashi Nakabayashi, Tatsuo Fujimoto, Mitsuru Sawamura, Noboru Ohtani
  • Patent number: 7767021
    Abstract: A growing method of a SiC single crystal includes the steps of thermal treatment of a high purity SiC source for decreasing a specific surface area and increasing a ratio of ?-phase and making a mole fraction of C greater than that of Si in the source, providing the SiC source into a crucible, arranging a SiC seed in the crucible, and growing the SiC single crystal by heating the SiC source.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: August 3, 2010
    Assignee: NeosemiTech Corporation
    Inventors: Soo-Hyung Seo, Joon-Suk Song, Myung-Hwan Oh
  • Patent number: 7754609
    Abstract: The cleaning of silicon carbide materials on a large-scale is described. Certain silicon carbide materials in the form of wafer-lift pins, wafer-rings and/or wafer-showerheads are cleaned by using a combination of two of more of the following steps, comprising: high temperature oxidation, scrubbing, ultrasonic assisted etching in an aqueous acid solution, ultrasonication in deionized water, immersion in an aqueous acid solution, and high temperature baking. The silicon carbide materials may either be sintered or formed by chemical vapor deposition.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: July 13, 2010
    Assignee: Applied Materials, Inc.
    Inventor: Samantha S. H. Tan
  • Patent number: 7718000
    Abstract: One provides (101) disperse ultra-nanocrystalline diamond powder material that comprises a plurality of substantially ordered crystallites that are each sized no larger than about 10 nanometers. One then reacts (102) these crystallites with a metallic component. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also substantially preserving the thermal conductivity behavior of the disperse ultra-nanocrystalline diamond powder material. The reaction process can comprise combining (201) the crystallites with one or more metal salts in an aqueous solution and then heating (203) that aqueous solution to remove the water. This heating can occur in a reducing atmosphere (comprising, for example, hydrogen and/or methane) to also reduce the salt to metal.
    Type: Grant
    Filed: February 14, 2007
    Date of Patent: May 18, 2010
    Assignee: Dimerond Technologies, LLC
    Inventor: Dieter M. Gruen
  • Patent number: 7641736
    Abstract: A method of manufacturing an SiC single crystal wafer according to the present invention includes the steps of: (a) preparing an SiC single crystal wafer 10 with a mirror-polished surface; (b) oxidizing the surface of the SiC single crystal wafer 10 with plasma, thereby forming an oxide layer 12 on the surface of the SiC single crystal wafer; and (c) removing at least a portion of the oxide layer 12 by a reactive ion etching process. Preferably, the surface of the wafer is planarized by repeatedly performing the steps (b) and (c) a number of times.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: January 5, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventor: Taisuke Hirooka
  • Patent number: 7637998
    Abstract: Single crystal SiC, having no fine grain boundaries, a micropipe defect density of 1/cm2 or less and a crystal terrace of 10 micrometer or more is obtained by a high-temperature liquid phase growth method using a very thin Si melt layer. The method does not require temperature difference control between the growing crystal surface and a raw material supply polycrystal and preparation of a doped single crystal SiC is possible.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: December 29, 2009
    Assignee: Kwansei Gakuin Educational Foundation
    Inventors: Tadaaki Kaneko, Yasushi Asaoka, Naokatsu Sano
  • Patent number: 7635413
    Abstract: A SiC single crystal is produced by the solution growth method in which a seed crystal attached to a seed shaft is immersed in a solution of SiC dissolved in a melt of Si or a Si alloy and a SiC single crystal is allowed to grow on the seed crystal by gradually cooling the solution or by providing a temperature gradient therein. To this method, accelerated rotation of a crucible is applied by repeatedly accelerating to a prescribed rotational speed and holding at that speed and decelerating to a lower rotational speed or a 0 rotational speed. The rotational direction of the crucible may be reversed each acceleration. The seed shaft may also be rotated synchronously with the rotation of the crucible in the same or opposite rotational as the crucible. A large, good quality single crystal having no inclusions are produced with a high crystal growth rate.
    Type: Grant
    Filed: March 1, 2007
    Date of Patent: December 22, 2009
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Kazuhiko Kusunoki, Kazuhito Kamei, Nobuyoshi Yashiro, Akihiro Yauchi, Yoshihisa Ueda, Yutaka Itoh, Nobuhiro Okada
  • Patent number: 7625447
    Abstract: SiC is a very stable substance, and it is difficult to control the condition of a SiC surface to be suitable for crystal growth in conventional Group III nitride crystal growing apparatuses. This problem is solved as follows. The surface of a SiC substrate 1 is rendered into a step-terrace structure by performing a heating process in an atmosphere of HCl gas. The surface of the SiC substrate 1 is then treated sequentially with aqua regia, hydrochloric acid, and hydrofluoric acid. A small amount of silicon oxide film formed on the surface of the SiC substrate 1 is etched so as to form a clean SiC surface 3 on the substrate surface. The SiC substrate 1 is then installed in a high-vacuum apparatus and the pressure inside is maintained at ultrahigh vacuum (such as 10?6 to 10?8 Pa). In the ultrahigh vacuum state, a process of irradiating the surface with a Ga atomic beam 5 at time t1 at temperature of 800° C. or lower and performing a heating treatment at 800° C. or higher is repeated at least once.
    Type: Grant
    Filed: March 18, 2004
    Date of Patent: December 1, 2009
    Assignee: Japan Science and Technology Agency
    Inventors: Jun Suda, Hiroyuki Matsunami, Norio Onojima
  • Patent number: 7601441
    Abstract: A single polytype single crystal silicon carbide wafer is disclosed having a diameter greater than three inches and less than five inches, resistivity greater than 10,000 ohm-cm, a micropipe density less than 200 cm?2, and a combined concentration of shallow level dopants less than 5E16 cm?3.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: October 13, 2009
    Assignee: Cree, Inc.
    Inventors: Jason Ronald Jenny, David Phillip Malta, Hudson McDonald Hobgood, Stephan Georg Mueller, Mark Brady, Robert Tyler Leonard, Adrian Powell, Valerl F. Tsvetkov
  • Patent number: 7588636
    Abstract: A method of production of a silicon carbide single crystal enabling fast, stable, and continuous growth of a high quality silicon carbide single crystal and enabling both an increase in size of the bulk single crystal and an improvement of quality of a thin film single crystal, comprising stacking, in order from the bottom, a silicon carbide source material rod, a solvent, a seed crystal, and a support rod supporting the seed crystal at its bottom end so as to form a columnar workpiece, heating a bottom end of the source material rod as a bottom end of the columnar workpiece, and cooling a top end of the support rod as the top end of the columnar workpiece so as to form a temperature gradient inside the columnar workpiece so that the top end face becomes lower in temperature than the bottom end face of the solvent; and causing a silicon carbide single crystal to grow continuously downwardly starting from the seed crystal, wherein said method further comprises using an inside cylindrical susceptor tightly surr
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: September 15, 2009
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Masateru Nakamura
  • Patent number: 7582357
    Abstract: The present invention can provide a silicon semiconductor substrate used for and epitaxial wafer, in which uniform and high-level gettering ability is obtained irrespective of slicing positions from a silicon single crystal while generation of epitaxial defects can be suppressed, by doping carbon or carbon along with nitrogen during a pulling process of a CZ method or by performing appropriate heat treatment prior to the epitaxial process. Therefore, a crystal production yield can remarkably be improved because a permissible upper limit (concentration margin) of an oxygen concentration which is restricted by formation of a ring-shaped OSF region can be higher and also an excellent gettering ability is exhibited, while allowing an epitaxial wafer to be produced wherein epitaxial defects attributable to substrate crystal defects are not formed.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: September 1, 2009
    Assignee: Sumco Corporation
    Inventor: Yasuo Koike
  • Patent number: 7572332
    Abstract: One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: August 11, 2009
    Assignee: Dimerond Technologies, LLC
    Inventor: Dieter M. Gruen
  • Patent number: 7553373
    Abstract: A method of producing a silicon carbide single crystal, having: fixing a seed crystal, including setting a seed crystal on a seed crystal fixing part with interposition of an adhesive; applying a uniform pressure on the entire surface of the seed crystal by contacting a flexible bag which is inflatable and deflatable to the seed crystal by charging a gas into the to flexible bag; hardening the adhesive; and sublimating a silicon carbide powder obtained by calcinating a mixture containing at least a silicon source and a resol xylene resin, having a nitrogen content of 100 mass ppm or less and having a content of each impurity elements of 0.1 mass ppm or less, and re-crystallizing for growing a silicon carbide single crystal.
    Type: Grant
    Filed: May 18, 2006
    Date of Patent: June 30, 2009
    Assignee: Bridgestone Corporation
    Inventors: Masashi Otsuki, Takayuki Maruyama, Shigeki Endo, Daisuke Kondo, Takuya Monbara
  • Patent number: 7544249
    Abstract: From the viewpoint of manufacturing an SiC semiconductor device economically, a present Si device manufacturing line is utilized to make it possible to handle a small-diameter SiC wafer. Polycrystal SiC is grown from at least one surface side of a small-diameter a-SiC single crystal wafer so as to be in a size of an outer diameter corresponding to a handling device of an existing semiconductor manufacturing line, and thereafter the polycrystal SiC on the surface of the ?-SiC single crystal wafer is ground to manufacture an increased-diameter SiC of a double structure in which the polycrystal SiC is grown around an outer circumference of the small-diameter ?-SiC single crystal wafer.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: June 9, 2009
    Assignee: Mitsui Engineering Co. Ltd.
    Inventors: Shigehiro Nishino, Kazutoshi Murata
  • Patent number: 7531433
    Abstract: A method for producing, on an SiC substrate, SiC homoepitaxial layers of the same polytype as the substrate. The layers are grown on a surface of the SiC substrate, wherein the surface is inclined relative to the (0001) basal plane at an angle higher than 0.1 degree but less than 1 degree. An homoepitaxial growth is started by forming a boundary layer with a thickness up to 1 ?m.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: May 12, 2009
    Assignee: Norstel AB
    Inventors: Alexandre Ellison, Christer Hallin, Björn Magnusson, Peder Bergman
  • Patent number: 7520930
    Abstract: A bulk silicon carbide single crystal of good crystalline quality which includes a minimized number of structural defects and is free from micropipe defects can be produced by crystal growth in a melt of an alloy comprising Si, C, and M (wherein M is either Mn or Ti) and having an atomic ratio between Si and M in which the value of x, when express as Si1-xMx, is 0.1?x?0.7 in the case where M is Mn or 0.1?x?0.25 in the case where M is Ti at a temperature of the melt which is below 2000° C. The C component is preferably supplied into the melt by dissolution of a graphite crucible which contains the melt such that the melt is free from undissolved C. One method of crystal growth is performed by cooling the melt after a seed substrate is immersed in the melt.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: April 21, 2009
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Kazuhiko Kusunoki, Shinji Munetoh, Kazuhito Kamei
  • Patent number: 7501022
    Abstract: Methods for producing silicon carbide crystals, seed crystal holders and seed crystal for use in producing silicon carbide crystals and silicon carbide crystals are provided. Silicon carbide crystals are produced by forcing nucleation sites of a silicon carbide seed crystal to a predefined pattern and growing silicon carbide utilizing physical vapor transport (PVT) so as to provide selective preferential growth of silicon carbide corresponding to the predefined pattern. Seed holders and seed crystals are provided for such methods. Silicon carbide crystals having regions of higher and lower defect density are also provided.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: March 10, 2009
    Assignee: Cree, Inc.
    Inventor: Stephan Mueller