Patents Examined by Hua Qi
  • Seed crystal holder for pulling up single crystal and method of manufacturing silicon single crystal using the same
    Patent number: 10822717
    Abstract: A seed crystal holder for pulling up a single crystal is made of a carbon fiber-reinforced carbon composite material, and has a substantially cylindrical shape with a hollow space having a shape matching an outer shape of a substantially rod-shaped seed crystal. A direction of carbon fibers at a part in contact with at least an outer peripheral surface of the seed crystal has isotropy as viewed from a central axis of the hollow space.
    Type: Grant
    Filed: July 3, 2019
    Date of Patent: November 3, 2020
    Assignee: SUMCO CORPORATION
    Inventor: Eiichi Kawasaki
  • Method for producing bulk silicon carbide
    Patent number: 10801126
    Abstract: A method of producing silicon carbide is disclosed. The method comprises the steps of providing a sublimation furnace comprising a furnace shell, at least one heating element positioned outside the furnace shell, and a hot zone positioned inside the furnace shell surrounded by insulation. The hot zone comprises a crucible with a silicon carbide precursor positioned in the lower region and a silicon carbide seed positioned in the upper region. The hot zone is heated to sublimate the silicon carbide precursor, forming silicon carbide on the bottom surface of the silicon carbide seed. Also disclosed is the sublimation furnace to produce the silicon carbide as well as the resulting silicon carbide material.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: October 13, 2020
    Assignee: GTAT Corporation
    Inventors: Roman V. Drachev, Parthasarathy Santhanaraghavan, Andriy M. Andrukhiv, David S. Lyttle
  • Method and apparatus for producing bulk silicon carbide using a silicon carbide seed
    Patent number: 10793971
    Abstract: A method of producing silicon carbide is disclosed. The method comprises the steps of providing a sublimation furnace comprising a furnace shell, at least one heating element positioned outside the furnace shell, and a hot zone positioned inside the furnace shell surrounded by insulation. The hot zone comprises a crucible with a silicon carbide precursor positioned in the lower region and a silicon carbide seed positioned in the upper region. The hot zone is heated to sublimate the silicon carbide precursor, forming silicon carbide on the bottom surface of the silicon carbide seed. Also disclosed is the sublimation furnace to produce the silicon carbide as well as the resulting silicon carbide material.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: October 6, 2020
    Assignee: GTAT Corporation
    Inventors: Roman V. Drachev, Andriy M. Andrukhiv, David S. Lyttle, Parthasarathy Santhanaraghavan
  • Cleaning method and laminate of aluminum nitride single-crystal substrate
    Patent number: 10753011
    Abstract: A method for effectively removing minute impurities of 1 ?m or less in size that are present on a surface of an aluminum nitride single-crystal substrate without etching the surface includes scrubbing a surface of an aluminum nitride single-crystal substrate using a polymer compound material having lower hardness than an aluminum nitride single crystal, and an alkali aqueous solution having 0.01-1 mass % concentration of potassium hydroxide or sodium hydroxide, the alkali aqueous solution being absorbed in the polymer compound material.
    Type: Grant
    Filed: August 21, 2015
    Date of Patent: August 25, 2020
    Assignee: Tokuyama Corporation
    Inventor: Masao Ariyuki
  • Epitaxial silicon carbide single crystal wafer and process for producing the same
    Patent number: 10727047
    Abstract: An epitaxial silicon carbide single crystal wafer and a method for producing the same, wherein the epitaxial silicon carbide single crystal wafer is produced by forming a buffer layer made of a silicon carbide epitaxial film having a thickness of 1 ?m or more and 10 ?m or less by adjusting the ratio of the number of carbon to that of silicon (C/Si ratio) contained in a silicon-based and carbon-based material gas to 0.5 or more and 1.0 or less, and then by forming a drift layer made of a silicon carbide epitaxial film at a growth rate of 15 ?m or more and 100 ?m or less per hour, thereby bringing a depth of shallow pits observed on the surface of the drift layer to 30 nm or less.
    Type: Grant
    Filed: February 16, 2016
    Date of Patent: July 28, 2020
    Assignee: SHOWA DENKO K.K.
    Inventors: Takashi Aigo, Wataru Ito, Tatsuo Fujimoto
  • Device of manufacturing silicon carbide single crystal
    Patent number: 10724151
    Abstract: A device of manufacturing a silicon carbide single crystal includes a crucible, a first resistive heater, a second resistive heater, and a first support portion. The crucible has a top surface, a bottom surface opposite to the top surface, and a tubular side surface located between the top surface and the bottom surface. The first resistive heater is disposed to face the bottom surface. The second resistive heater is provided to surround the side surface. The first support portion supports the crucible such that the bottom surface is separated from the first resistive heater, and the side surface is separated from the second resistive heater. The first support portion is in contact with at least one of the top surface and the side surface.
    Type: Grant
    Filed: August 25, 2015
    Date of Patent: July 28, 2020
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tsutomu Hori, Shin Harada
  • Method for producing silicon single crystal
    Patent number: 10711368
    Abstract: A manufacturing method of monocrystalline silicon includes: melting silicon housed in a quartz crucible into a silicon melt by heating the quartz crucible with a heating unit; dipping a seed crystal into the silicon melt in the quartz crucible to bring the seed crystal into contact with the silicon melt; and pulling up the seed crystal to grow monocrystalline silicon. In the pulling-up, a formation of a straight body of the monocrystalline silicon is started at a power consumption of the heating unit being equal to or more than 10000 kWh to grow an entirety of the monocrystalline silicon.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: July 14, 2020
    Assignee: SUMCO CORPORATION
    Inventor: Tegi Kim
  • Radiation shield
    Patent number: 10692741
    Abstract: A radiation shield and an assembly and a reactor including the radiation shield are disclosed. The radiation shield can be used to control heat flux from a susceptor heater assembly and thereby enable better control of temperatures across a surface of a substrate placed on a surface of the susceptor heater assembly.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: June 23, 2020
    Assignee: ASM IP Holdings B.V.
    Inventor: Melvin Verbaas
  • Method of evaluating manufacturing process of silicon material and manufacturing method of silicon material
    Patent number: 10676840
    Abstract: The method is a method of evaluating a manufacturing process of a silicon material, wherein the manufacturing process includes a process that uses a member containing a carbon-containing sintered body, and the method of evaluating the manufacturing process of a silicon material includes performing DLTS measurement on a silicon material manufactured in the manufacturing process, and estimating a heavy metal contamination source of a silicon material manufactured in the manufacturing process with an indicator in the form of presence/absence of detection of a peak of a carbon-related level and presence/absence of detection of a peak of a heavy metal-related level in a DLTS spectrum obtained by the DLTS measurement.
    Type: Grant
    Filed: October 19, 2017
    Date of Patent: June 9, 2020
    Assignee: SUMCO CORPORATION
    Inventors: Noritomo Mitsugi, Kazutaka Eriguchi, Shuichi Samata, Ayumi Masada
  • Isotropic atomic layer etch for silicon oxides using no activation
    Patent number: 10679868
    Abstract: Methods for controlled isotropic etching of layers of silicon oxide and germanium oxide with atomic scale fidelity are provided. The methods make use of NO activation of an oxide surface. Once activated, a fluorine-containing gas or vapor etches the activated surface. Etching is self-limiting as once the activated surface is removed, etching stops since the fluorine species does not spontaneously react with the un-activated oxide surface. These methods may be used in interconnect pre-clean applications, gate dielectric processing, manufacturing of memory devices, or any other applications where accurate removal of one or multiple atomic layers of material is desired.
    Type: Grant
    Filed: July 21, 2016
    Date of Patent: June 9, 2020
    Assignee: LAM RESEARCH CORPORATION
    Inventors: Ivan L. Berry, III, Pilyeon Park, Faisal Yaqoob
  • Method for achieving sustained anisotropic crystal growth on the surface of a silicon melt
    Patent number: 10662548
    Abstract: An apparatus for growing a crystalline sheet from a melt includes a cold block assembly. The cold block assembly may include a cold block and a shield surrounding the cold block and being at an elevated temperature with respect to that of the cold block, the shield defining an opening disposed along a surface of the cold block proximate a melt surface that defines a cold area comprising a width along a first direction of the cold block, the cold area operable to provide localized cooling of a region of the melt surface proximate the cold block. The apparatus may further include a crystal puller arranged to draw a crystalline seed in a direction perpendicular to the first direction when the cold block assembly is disposed proximate the melt surface.
    Type: Grant
    Filed: March 16, 2018
    Date of Patent: May 26, 2020
    Assignee: Leading Edge Crystal Technologies, Inc.
    Inventors: Brian H. Mackintosh, Peter L. Kellerman, Dawei Sun
  • Method and system for producing crystalline calcium carbonate by the combined use of two gases with different COcontent
    Patent number: 10662546
    Abstract: The invention relates to a particularly energy efficient, two-step method and to a system for the continuous or semicontinuous production of crystalline calcium carbonate (precipitated calcium carbonate, PCC) by reacting calcium hydroxide with CO2, the calcium hydroxide being lime milk. In the first step of the germination, the CO2-source is exclusively flue gas having a CO2-content of between 4-25% <sb/><sb/>. In the second step, the complete conversion of the lime milk reacted in the first step to a maximum of 90%, preferably between 10-90%, is carried out exclusively using a rich gas which comprises 30-99% CO2, preferably using biogas.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: May 26, 2020
    Assignee: PAPIERFABRIK AUGUST KOEHLER SE
    Inventors: Heinrich Follmann, Berit Hillbrecht
  • Method and apparatus for producing epitaxial wafer
    Patent number: 10640883
    Abstract: After removing deposit on a susceptor in an epitaxial growth furnace by a cleaning recipe (step S101), a first epitaxial wafer is produced by growing an epitaxial layer on a first wafer based on a process recipe A (step S102). Subsequently, a step of producing an epitaxial wafer by growing an epitaxial layer on a wafer based on a process recipe B including second control parameters set such that the epitaxial wafer has approximately the same film thickness profile as the first wafer (step S103) is repeated a plurality of times to successively produce a plurality of epitaxial wafers (step S104). The cleaning recipe, the process recipe A, and the process recipe B repeated a plurality of times are carried out repeatedly (step S105).
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: May 5, 2020
    Assignee: SUMCO Corporation
    Inventors: Kenji Sakamoto, Masayuki Tsuji
  • Technique for controlling temperature uniformity in crystal growth apparatus
    Patent number: 10633759
    Abstract: A sapphire crystal growth apparatus is provided that includes a chamber, a hot zone and a muffle. More specifically, the hot zone is disposed within the chamber and includes at least one heating system, at least one heat removal system, and a crucible containing feedstock. Additionally, a muffle that surrounds at least two sides of the crucible is also provided to ensure uniform temperature distribution through the feedstock during crystal growth to allow the crystalline material to be grown with a square or rectangular shaped cross section.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: April 28, 2020
    Assignee: GTAT Corporation
    Inventors: Frederick Schmid, Cody Riopel, Hui Zhang
  • Process for determining surface contamination of polycrystalline silicon
    Patent number: 10605659
    Abstract: The invention provides a process for determining surface contamination of polycrystalline silicon, including the steps of: a) providing two polycrystalline silicon rods by deposition in a Siemens reactor; b) determining contaminants in the first of the two rods immediately after the deposition; c) conducting the second rod through one or more systems in which polycrystalline silicon rods are processed further to give rod pieces or polysilicon fragments, optionally cleaned, stored or packed; d) then determining contaminants in the second rod; wherein the difference in the contaminants determined in the first and second rods gives surface contamination of polycrystalline silicon resulting from systems and the system environment.
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: March 31, 2020
    Assignee: WACKER CHEMIE AG
    Inventors: Hanns Wochner, Robert Baumann
  • Apparatus and method for producing gallium oxide crystal
    Patent number: 10570528
    Abstract: The apparatus for producing a gallium oxide crystal relating to the invention contains a vertical Bridgman furnace containing: a base body; a cylindrical furnace body having heat resistance disposed above the base body; a lid member occluding the furnace body; a heater disposed inside the furnace body; a crucible shaft provided vertically movably through the base body; and a crucible disposed on the crucible shaft, heated with the heater, the crucible is a crucible containing a Pt-based alloy, the furnace body has an inner wall that is formed as a heat-resistant wall containing plural ring shaped heat-resistant members each having a prescribed height accumulated on each other, and the ring shaped heat-resistant members each contain plural divided pieces that are joined to each other to the ring shape.
    Type: Grant
    Filed: March 27, 2017
    Date of Patent: February 25, 2020
    Assignees: SHINSHU UNIVERSITY, FUJIKOSHI MACHINERY CORP.
    Inventors: Keigo Hoshikawa, Takumi Kobayashi, Etsuko Ohba, Jun Yanagisawa
  • Growth of a uniformly doped silicon ingot by doping only the initial charge
    Patent number: 10544517
    Abstract: The present invention relates to a method of growing a silicon ingot comprising a dopant material having a segregation coefficient of k, wherein the concentration of the dopant is axially substantially uniform throughout the ingot. The method comprises the steps of providing a crucible having an inner growth zone in fluid communication with an outer feed zone, and the inner growth zone and the outer feed zone have cross-sectional areas that are can be used to determine conditions for maintaining dopant uniformity for the specific dopant material used. A crystalline growth system for growing at least one uniformly doped silicon ingot is also disclosed.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: January 28, 2020
    Assignee: GTAT IP HOLDING LLC.
    Inventor: Bayard K. Johnson
  • Method of producing high purity SiOx nanoparticles with excellent volatility and apparatus for producing the same
    Patent number: 10541407
    Abstract: The present disclosure provides a method of producing high purity SiOx nanoparticles with excellent volatility and an apparatus for producing the same, which enables mass production of SiOx nanoparticles by melting silicon through induction heating and injecting gas to a surface of the molten silicon. The apparatus includes a vacuum chamber, a graphite crucible into which raw silicon is charged, the graphite crucible being mounted inside the vacuum chamber, an induction melting part which forms molten silicon by induction heating of the silicon material received in the graphite crucible, a gas injector which injects a gas into the graphite crucible to be brought into direct contact with a surface of the molten silicon, and a collector disposed above the graphite crucible and collecting SiOx vapor produced by reaction between the molten silicon and the injected gas.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: January 21, 2020
    Assignee: KOREA INSTITUTE OF ENERGY RESEARCH
    Inventors: Bo-Yun Jang, Jin-Seok Lee, Joon-Soo Kim
  • Devices and methods for electrochemical liquid phase epitaxy
    Patent number: 10538860
    Abstract: Electrochemical liquid phase epitaxy (ec-LPE) processes and devices are provided that can form precipitated epitaxial crystalline films or layers on a substrate. The precipitated films may comprise a semiconductor, such as germanium, silicon, or carbon. Dissolution into, saturation within, and precipitation of the semiconductor from a liquid metal electrode (e.g., Hg pool) near an interface region with a substrate yields a polycrystalline semiconductor material deposited as an epitaxial film. Reactor cells for use in an electrochemical liquid phase epitaxy (ec-LPE) device are also provided that include porous membranes to facilitate formation of the precipitated epitaxial crystalline films.
    Type: Grant
    Filed: January 9, 2018
    Date of Patent: January 21, 2020
    Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Stephen Maldonado, Joshua DeMuth, Eli Fahrenkrug
  • Method for growing ?-GAO-based single crystal
    Patent number: 10526721
    Abstract: Provided is a method for growing a ?-Ga2O3-based single crystal, whereby it becomes possible to grow a ?-Ga2O3-based single crystal having a small variation in crystal structure and also having a high quality in the direction of a b axis. In one embodiment, a method for growing a ?-Ga2O3-based single crystal includes growing a plate-shaped Sn doped ?-Ga2O3-based single crystal in the direction of the b axis using a seed crystal.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: January 7, 2020
    Assignees: KOHA CO., LTD., TAMURA CORPORATION
    Inventors: Shinya Watanabe, Kazuyuki Iizuka, Kei Doioka, Haruka Matsubara, Takekazu Masui