Nitride Containing (e.g., Gan, Cbn) {c30b 29/38} Patents (Class 117/952)
  • Patent number: 10337120
    Abstract: An alumina substrate having a carbon-containing phase with an AlN layer formed on a surface of the alumina substrate.
    Type: Grant
    Filed: August 6, 2015
    Date of Patent: July 2, 2019
    Assignee: TDK CORPORATION
    Inventors: Kazuhito Yamasawa, Atsushi Ohido, Katsumi Kawasaki
  • Patent number: 10186451
    Abstract: A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a-group III-nitride-film-side main surface of the group III nitride composite substrate is 200 ?/sq or less. A method for manufacturing a group III nitride composite substrate includes the steps of bonding the group III nitride film and the support substrate to each other; and reducing the thickness of at least one of the group III nitride film and the support substrate bonded to each other. Accordingly, a group III nitride composite substrate of a low sheet resistance that is obtained with a high yield as well as a method for manufacturing the same are provided.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: January 22, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiro Hachigo, Keiji Ishibashi, Naoki Matsumoto
  • Patent number: 10141184
    Abstract: Crystal growth of GaN is performed on a growth layer (103a) in a state in which the main surface is set to an N-polarity, thereby forming a boule (104) made of a GaN crystal. GaN is epitaxially grown using each growth island as a nucleus forming the growth layer (103a) by an MOVPE method using ammonia and trimethylgallium as source gases in accordance with a continuous process using an MOVPE apparatus used in the formation of a buffer layer (102).
    Type: Grant
    Filed: January 22, 2016
    Date of Patent: November 27, 2018
    Assignee: TOHOKU UNIVERSITY
    Inventor: Takashi Matsuoka
  • Patent number: 9970127
    Abstract: Bulk single crystals of AlN having a diameter greater than about 25 mm and dislocation densities of about 10,000 cm?2 or less and high-quality AlN substrates having surfaces of any desired crystallographic orientation fabricated from these bulk crystals.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: May 15, 2018
    Assignee: CRYSTAL IS, INC.
    Inventors: Leo Schowalter, Glen A. Slack, Juan Carlos Rojo, Robert T. Bondokov, Kenneth E. Morgan, Joseph A. Smart
  • Patent number: 9899564
    Abstract: A Group III nitride semiconductor containing: a RAMO4 substrate containing a single crystal represented by the general formula RAMO4 (wherein R represents one or a plurality of trivalent elements selected from the group consisting of Sc, In, Y, and a lanthanoid element, A represents one or a plurality of trivalent elements selected from the group consisting of Fe(III), Ga, and Al, and M represents one or a plurality of divalent elements selected from the group consisting of Mg, Mn, Fe(II), Co, Cu, Zn, and Cd), and a Group III nitride crystal disposed above the RAMO4 substrate, having therebetween a dissimilar film that contains a material different from the RAMO4 substrate, and has plural openings.
    Type: Grant
    Filed: February 13, 2017
    Date of Patent: February 20, 2018
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Akihiko Ishibashi, Akio Ueta
  • Patent number: 9627197
    Abstract: The invention provides a composite substrate, a semiconductor device including such composite substrate, and a method of making the same. In particular, the composite substrate of the invention includes a nitride-based single crystal layer transformed from a nitride-based poly-crystal layer, which has a specific thickness of approximately between 2 nm and 100 nm.
    Type: Grant
    Filed: April 15, 2015
    Date of Patent: April 18, 2017
    Assignee: GLOBALWAFERS CO., LTD.
    Inventors: Miin-Jang Chen, Huan-Yu Shih, Wen-Ching Hsu, Ray-Ming Lin
  • Patent number: 9039834
    Abstract: Non-polar (11 20) a-plane gallium nitride (GaN) films with planar surfaces are grown on (1 102) r-plane sapphire substrates by employing a low temperature nucleation layer as a buffer layer prior to a high temperature growth of the non-polar (11 20) a-plane GaN thin films.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: May 26, 2015
    Assignee: The Regents of the University of California
    Inventors: Michael D. Craven, James Stephen Speck
  • Patent number: 9034103
    Abstract: In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: May 19, 2015
    Assignee: CRYSTAL IS, INC.
    Inventors: Sandra B. Schujman, Shailaja P. Rao, Robert T. Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • 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: 8999059
    Abstract: A growth apparatus is used having a plurality of crucibles each for containing the solution, a heating element for heating the crucible, and a pressure vessel for containing at least the crucibles and the heating element and for filling an atmosphere comprising at least nitrogen gas. One seed crystal is put in each of the crucibles to grow the nitride single crystal on the seed crystal.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: April 7, 2015
    Assignees: NGK Insulators, Ltd., Osaka University
    Inventors: Katsuhiro Imai, Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8986835
    Abstract: A GaN nanorod and formation method. Formation includes providing a substrate having a GaN film, depositing SiNx on the GaN film, etching a growth opening through the SiNx and into the GaN film, growing a GaN nanorod through the growth opening, the nanorod having a nanopore running substantially through its centerline. Focused ion beam etching can be used. The growing can be done using organometallic vapor phase epitaxy. The nanopore diameter can be controlled using the growth opening diameter or the growing step duration. The GaN nanorods can be removed from the substrate. The SiNx layer can be removed after the growing step. A SiOx template can be formed on the GaN film and the GaN can be grown to cover the SiOx template before depositing SiNx on the GaN film. The SiOx template can be removed after growing the nanorods.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: March 24, 2015
    Assignee: Purdue Research Foundation
    Inventors: Isaac Harshman Wildeson, Timothy David Sands
  • Patent number: 8921980
    Abstract: An aluminum nitride single crystal in the form of polygonal columns, the polygonal columns having the following properties [a] to [c]: [a] the content of a metal impurity is below a detection limit, [b] the average bottom area is from 5×103 to 2×105 ?m2, and [c] the average height is 50 ?m to 5 mm. The above aluminum nitride single crystal is preferably obtainable in a method including the steps of sublimating an aluminum nitride starting material (A) containing 0.1 to 30% by mass of a rare earth oxide by heating the starting material at a temperature of not lower than 2000° C., depositing aluminum nitride on a hexagonal single crystal substrate and thereby growing aluminum nitride single crystal in the shape of polygonal columns.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: December 30, 2014
    Assignees: Meijo University, Tokuyama Corporation
    Inventors: Hiroshi Amano, Yukihiro Kanechika, Masanobu Azuma
  • Patent number: 8916124
    Abstract: 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: Grant
    Filed: November 27, 2008
    Date of Patent: December 23, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Minemoto, Osamu Yamada, Takeshi Hatakeyama, Hiroaki Hoshikawa, Yasunori Tokunou
  • Patent number: 8900362
    Abstract: A method of growing a single crystal of gallium oxide at a lower temperature than the melting point (1900° C.) of gallium oxide is provided. A compound film (hereinafter referred to as “gallium oxide compound film”) containing Ga atoms, O atoms, and atoms or molecules that easily sublimate, is heated to sublimate the atoms or molecules that easily sublimate from inside the gallium oxide compound film, thereby growing a single crystal of gallium oxide with a heat energy that is lower than a binding energy of gallium oxide.
    Type: Grant
    Filed: March 8, 2011
    Date of Patent: December 2, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Akiharu Miyanaga, Tatsuya Honda, Takatsugu Omata, Yusuke Nonaka
  • Patent number: 8888914
    Abstract: The object is to provide a photoelectric surface member which allows higher quantum efficiency. In order to achieve this object, a photoelectric surface member 1a is a crystalline layer formed by a nitride type semiconductor material, and comprises a nitride semiconductor crystal layer 10 where the direction from the first surface 101 to the second surface 102 is the negative c polar direction of the crystal, an adhesive layer 12 formed along the first surface 101 of the nitride semiconductor crystal layer 10, and a glass substrate 14 which is adhesively fixed to the adhesive layer 12 such that the adhesive layer 12 is located between the glass substrate 14 and the nitride semiconductor crystal layer 10.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: November 18, 2014
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Tokuaki Nihashi, Masatomo Sumiya, Minoru Hagino, Shunro Fuke
  • Patent number: 8882910
    Abstract: A substrate is formed of AlxGa1-xN, wherein 0<x?1. The substrate is a single crystal and is used producing a Group III nitride semiconductor device. A method for producing a substrate of AlxGa1-xN, wherein 0<x?1, includes the steps of forming a layer of AlxGa1-xN, wherein 0<x?1, on a base material and removing the base material. The method adopts the MOCVD method using a raw material molar ratio of a Group V element to Group III element that is 1000 or less, a temperature of 1200° C. or more for forming the layer of AlxGa1-xN, wherein 0<x?1. The base material is formed of one member selected from the group consisting of sapphire, SiC, Si, ZnO and Ga2O3. The substrate is used for fabricating a Group III nitride semiconductor device.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: November 11, 2014
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Hiroshi Amano, Akira Bando
  • Patent number: 8872309
    Abstract: Group-III nitride crystal composites made up of especially processed crystal slices, cut from III-nitride bulk crystal, whose major surfaces are of {1-10±2}, {11-2±2}, {20-2±1} or {22-4±1} orientation, disposed adjoining each other sideways with the major-surface side of each slice facing up, and III-nitride crystal epitaxially present on the major surfaces of the adjoining slices, with the III-nitride crystal containing, as principal impurities, either silicon atoms or oxygen atoms.
    Type: Grant
    Filed: March 3, 2014
    Date of Patent: October 28, 2014
    Assignee: Sumitomo Electronic Industries, Ltd.
    Inventors: Naho Mizuhara, Koji Uematsu, Michimasa Miyanaga, Keisuke Tanizaki, Hideaki Nakahata, Seiji Nakahata, Takuji Okahisa
  • Patent number: 8858708
    Abstract: This invention provides a process for producing high-purity dense polycrystalline III-nitride slabs. A vessel which contains a group III-metal such as gallium or an alloy of group III-metals of shallow depth is placed in a reactor. The group III-metal or alloy is heated until a molten state is reached after which a halide-containing source mixed with a carrier gas and a nitrogen-containing source is flowed through the reactor vessel. An initial porous crust of III-nitride forms on the surface of the molten III-metal or alloy which reacts with the nitrogen-containing source and the halide-containing source. The flow rate of the nitrogen-containing source is then increased and flowed into contact with the molten metal to produce a dense polycrystalline III-nitride. The products produced from the inventive process can be used as source material for III-nitride single crystal growth which material is not available naturally.
    Type: Grant
    Filed: June 17, 2010
    Date of Patent: October 14, 2014
    Assignee: The United States of America As represented by the Secretary of the Air Force
    Inventors: Michael J. Callahan, Buguo Wang, John S. Bailey
  • Patent number: 8829651
    Abstract: A nitride-based semiconductor substrate has a diameter of 25 mm or more, a thickness of 250 micrometers or more, a n-type carrier concentration of 1.2×1018 cm?3 or more and 3×1019 cm?3 or less, and a thermal conductivity of 1.2 W/cmK or more and 3.5 W/cmK or less. Alternatively, the substrate has an electron mobility ? [cm2/Vs] of more than a value represented by loge ?=17.7?0.288 loge n and less than a value represented by loge ?=18.5?0.288 loge n, where the substrate has a n-type carrier concentration n [cm?3] that is 1.2×1018 cm?3 or more and 3×1019 cm?3 or less.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: September 9, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventor: Yuichi Oshima
  • Patent number: 8778078
    Abstract: A process for producing a doped III-N bulk crystal, wherein III denotes at least one element of the main group III of the periodic system, selected from Al, Ga and In, wherein the doped crystalline III-N layer or the doped III-N bulk crystal is deposited on a substrate or template in a reactor, and wherein the feeding of at least one dopant into the reactor is carried out in admixture with at least one group III material. In this manner, III-N bulk crystals and III-N single crystal substrates separated therefrom can be obtained with a very homogeneous distribution of dopants in the growth direction as well as in the growth plane perpendicular thereto, a very homogeneous distribution of charge carriers and/or of the specific electric resistivity in the growth direction as well as in the growth plane perpendicular thereto, and a very good crystal quality.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: July 15, 2014
    Assignee: Freiberger Compound Materials GmbH
    Inventors: Ferdinand Scholz, Peter Brückner, Frank Habel, Gunnar Leibiger
  • Patent number: 8771552
    Abstract: A group III nitride crystal substrate is provided in which a uniform distortion at a surface layer of the crystal substrate represented by a value of |d1 ?d2 |/d2 obtained from a plane spacing d1 at the X-ray penetration depth of 0.3 ?m and a plane spacing d2 at the X-ray penetration depth of 5 ?m is equal to or lower than 1.9 ×10?3, and the main surface has a plane orientation inclined in the <10-10> direction at an angle equal to or greater than 10° and equal to or smaller than 80° with respect to one of (0001) and (000-1) planes of the crystal substrate. A group III nitride crystal substrate suitable for manufacturing a light emitting device with a blue shift of an emission suppressed, an epilayer-containing group III nitride crystal substrate, a semiconductor device and a method of manufacturing the same can thereby be provided.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: July 8, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keiji Ishibashi, Yusuke Yoshizumi
  • Patent number: 8758510
    Abstract: A method is used for producing an SiC volume monocrystal by sublimation growth. During growth, by sublimation of a 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 grows by deposition from the SiC growth gas phase on the SiC seed crystal. The SiC seed crystal is bent during a heating phase before such that an SiC crystal structure with a non-homogeneous course of lattice planes is adjusted, the lattice planes at each point have an angle of inclination relative to the direction of the center longitudinal axis and peripheral angles of inclination at a radial edge of the SiC seed crystal differ in terms of amount by at least 0.05° and at most by 0.2° from a central angle of inclination at the site of the center longitudinal axis.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: June 24, 2014
    Assignee: SiCrystal Aktiengesellschaft
    Inventors: Thomas Straubinger, Michael Vogel, Andreas Wohlfart
  • Patent number: 8735905
    Abstract: Provided is a method for producing inexpensive and high-quality aluminum nitride crystals. Gas containing N atoms is introduced into a melt of a Ga—Al alloy, whereby aluminum nitride crystals are made to epitaxially grow on a seed crystal substrate in the melt of the Ga—Al alloy. A growth temperature of aluminum nitride crystals is set at not less than 1000 degrees C. and not more than 1500 degrees C., thereby allowing GaN to be decomposed into Ga metal and nitrogen gas.
    Type: Grant
    Filed: July 14, 2011
    Date of Patent: May 27, 2014
    Assignees: Sumitomo Metal Mining Co., Ltd., Tohoku University
    Inventors: Hiroyuki Fukuyama, Masayoshi Adachi, Akikazu Tanaka, Kazuo Maeda
  • Patent number: 8709923
    Abstract: Provided is a method of manufacturing III-nitride crystal having a major surface of plane orientation other than {0001}, designated by choice, the III-nitride crystal manufacturing method including: a step of slicing III-nitride bulk crystal through a plurality of planes defining a predetermined slice thickness in the direction of the designated plane orientation, to produce a plurality of III-nitride crystal substrates having a major surface of the designated plane orientation; a step of disposing the substrates adjoining each other sideways in a manner such that the major surfaces of the substrates parallel each other and such that any difference in slice thickness between two adjoining III-nitride crystal substrates is not greater than 0.1 mm; and a step of growing III-nitride crystal onto the major surfaces of the substrates.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: April 29, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Naho Mizuhara, Koji Uematsu, Michimasa Miyanaga, Keisuke Tanizaki, Hideaki Nakahata, Seiji Nakahata, Takuji Okahisa
  • Patent number: 8617312
    Abstract: A method of forming (and system for forming) layers, such as calcium, barium, strontium, and/or magnesium, tantalates and/or niobates, and optionally titanates, on a substrate by employing a vapor deposition method, particularly a multi-cycle atomic layer deposition process.
    Type: Grant
    Filed: September 14, 2006
    Date of Patent: December 31, 2013
    Assignee: Micron Technology, Inc.
    Inventors: Brian A. Vaartstra, Stefan Uhlenbrock
  • Patent number: 8580035
    Abstract: Reducing the microvoid (MV) density in AlN ameliorates numerous problems related to cracking during crystal growth, etch pit generation during the polishing, reduction of the optical transparency in an AlN wafer, and, possibly, growth pit formation during epitaxial growth of AlN and/or AlGaN. This facilitates practical crystal production strategies and the formation of large, bulk AlN crystals with low defect densities—e.g., a dislocation density below 104 cm?2 and an inclusion density below 104 cm?3 and/or a MV density below 104 cm?3.
    Type: Grant
    Filed: December 6, 2012
    Date of Patent: November 12, 2013
    Assignee: Crystal IS, Inc.
    Inventors: Robert Bondokov, Kenneth E. Morgan, Glen A. Slack, Leo J. Schowalter
  • Patent number: 8574364
    Abstract: The invention relates to a GaN-crystal free-standing substrate obtained from a GaN crystal grown by HVPE with a (0001) plane serving as a crystal growth plane and at least one plane of a {10-11} plane and a {11-22} plane serving as a crystal growth plane that constitutes a facet crystal region, except for the side surface of the crystal, wherein the (0001)-plane-growth crystal region has a carbon concentration of 5×1016 atoms/cm3 or less, a silicon concentration of 5×1017 atoms/cm3 or more and 2×1018 atoms/cm3 or less, and an oxygen concentration of 1×1017 atoms/cm3 or less; and the facet crystal region has a carbon concentration of 3×1016 atoms/cm3 or less, a silicon concentration of 5×1017 atoms/cm3 or less, and an oxygen concentration of 5×1017 atoms/cm3 or more and 5×1018 atoms/cm3 or less.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: November 5, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shinsuke Fujiwara, Koji Uematsu, Hitoshi Kasai, Takuji Okahisa
  • Patent number: 8545629
    Abstract: Bulk single crystals of AlN having a diameter greater than about 25 mm and dislocation densities of about 10,000 cm?2 or less and high-quality AlN substrates having surfaces of any desired crystallographic orientation fabricated from these bulk crystals.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: October 1, 2013
    Assignee: Crystal IS, Inc.
    Inventors: Leo J. Schowalter, Glen A. Slack, J. Carlos Rojo, Robert T. Bondokov, Kenneth E. Morgan, Joseph A. Smart
  • Patent number: 8546167
    Abstract: A nitride-based semiconductor light-emitting element includes an n-GaN layer 102, a p-GaN layer 107, and a GaN/InGaN multi-quantum well active layer 105, which is interposed between the n- and p-GaN layers 102 and 107. The GaN/InGaN multi-quantum well active layer 105 is an m-plane semiconductor layer, which includes an InxGa1-xN (where 0<x<1) well layer 104 that has a thickness of 6 nm or more and 17 nm or less, and oxygen atoms included in the GaN/InGaN multi-quantum well active layer 105 have a concentration of 3.0×1017 cm?3 or less.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: October 1, 2013
    Assignee: Panasonic Corporation
    Inventors: Ryou Kato, Shunji Yoshida, Toshiya Yokogawa
  • Patent number: 8529697
    Abstract: A process for growing a crystal of a nitride semiconductor in which after the step of mounting a substrate (12) in a reaction tube (11), the step of feeding a first material gas containing a Group 3 element onto the substrate in the reaction tube and the step of feeding a second material gas containing elemental nitrogen onto the substrate in the reaction tube are carried out alternately to deposit a nitride semiconductor crystal directly on the substrate. The number of moles of the elemental nitrogen contained in the second material gas has a ratio of 200 or more to the number of moles of the Group 3 element in the first material gas.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: September 10, 2013
    Assignees: Honda Motor Co., Ltd.
    Inventors: Hideki Hashimoto, Akihiko Horiuchi, Hideo Kawanishi
  • Patent number: 8529696
    Abstract: A method for producing hexagonal boron nitride single crystals including mixing boron nitride crystals with a solvent thereby obtaining a mixture, heating and melting the mixture under high-temperature and high-pressure thereby obtaining a melted mixture, and recrystallizing the melted mixture thereby producing hexagonal boron nitride single crystals, wherein the solvent is boronitride of alkaline earth metal, or boronitride of alkali metal and the boronitride of alkaline earth metal.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: September 10, 2013
    Assignee: National Institute for Materials Science
    Inventors: Kenji Watanabe, Takashi Taniguchi, Satoshi Koizumi, Hisao Kanda, Masayuki Katagiri, Takatoshi Yamada, Nesladek Milos
  • Patent number: 8512471
    Abstract: In a physical vapor transport growth technique for silicon carbide a silicon carbide powder and a silicon carbide seed crystal are introduced into a physical vapor transport growth system and halosilane gas is introduced separately into the system. The source powder, the halosilane gas, and the seed crystal are heated in a manner that encourages physical vapor transport growth of silicon carbide on the seed crystal, as well as chemical transformations in the gas phase leading to reactions between halogen and chemical elements present in the growth system.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: August 20, 2013
    Assignee: II-VI Incorporated
    Inventors: Ilya Zwieback, Thomas E. Anderson, Avinash K. Gupta
  • Patent number: 8506705
    Abstract: 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: Grant
    Filed: September 9, 2009
    Date of Patent: August 13, 2013
    Assignee: NGK Insulators, Ltd.
    Inventors: Mikiya Ichimura, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Yasuo Kitaoka
  • Patent number: 8475593
    Abstract: 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: Grant
    Filed: June 28, 2011
    Date of Patent: July 2, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Hirokazu Iwata, Seiji Sarayama, Akihiro Fuse
  • Patent number: 8449671
    Abstract: A method of fabricating an SiC single crystal includes (a) physical vapor transport (PVT) growing a SiC single crystal on a seed crystal in the presence of a temperature gradient, wherein an early-to-grow portion of the SiC single crystal is at a lower temperature than a later-to-grow portion of the SiC single crystal. Once grown, the SiC single crystal is annealed in the presence of a reverse temperature gradient, wherein the later-to-grow portion of the SiC single crystal is at a lower temperature than the early-to-grow portion of the SiC single crystal.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: May 28, 2013
    Assignee: II-VI Incorporated
    Inventors: Ping Wu, Ilya Zwieback, Avinesh K. Gupta, Edward Semenas
  • Patent number: 8425858
    Abstract: An apparatus includes an article and a detector. The article includes a substrate, a faceted structure disposed on the substrate, and a sensor layer disposed on the faceted structure. The faceted structure is disposed on the substrate first surface and itself has a surface. The faceted structure surface has peripheral edge defining a diameter of the faceted structure surface. The sensor layer is disposed on the faceted structure surface. The sensor layer can react or can interact with a target species when the target species is sufficiently proximate to the sensor layer. The sensor layer responds to the reaction or to the interaction in a detectable manner. The detector detects a response to the reaction, or to the interaction, of the target species with the sensor layer.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: April 23, 2013
    Assignee: Morpho Detection, Inc.
    Inventors: Steven Francis LeBoeuf, Peter Micah Sandvik, Radislav Alexandrovich Potyrailo
  • Patent number: 8421190
    Abstract: A method of manufacturing a group III nitride semiconductor substrate includes the growth step of epitaxially growing a first group III nitride semiconductor layer on an underlying substrate, and the process step of forming a first group III nitride semiconductor substrate by cutting and/or surface-polishing the first group III nitride semiconductor layer. In the growth step, at least one element selected from the group consisting of C, Mg, Fe, Be, Zn, V, and Sb is added as an impurity element by at least 1×1017 cm?3 to the first group III nitride semiconductor layer. A group III nitride semiconductor substrate having controlled resistivity and low dislocation density and a manufacturing method thereof can thus be provided.
    Type: Grant
    Filed: October 7, 2010
    Date of Patent: April 16, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takuji Okahisa, Hideaki Nakahata, Seiji Nakahata
  • Patent number: 8404042
    Abstract: III-nitride crystal composites are made up of especially processed crystal slices cut from III-nitride bulk crystal having, ordinarily, a {0001} major surface and disposed adjoining each other sideways, and of III-nitride crystal epitaxially on the bulk-crystal slices. The slices are arranged in such a way that their major surfaces parallel each other, but are not necessarily flush with each other, and so that the [0001] directions in the slices are oriented in the same way.
    Type: Grant
    Filed: August 2, 2012
    Date of Patent: March 26, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Naho Mizuhara, Koji Uematsu, Michimasa Miyanaga, Keisuke Tanizaki, Hideaki Nakahata, Seiji Nakahata, Takuji Okahisa
  • Patent number: 8398767
    Abstract: Bulk mono-crystalline gallium-containing nitride, grown on the seed at least in the direction essentially perpendicular to the direction of the seed growth, essentially without propagation of crystalline defects as present in the seed, having the dislocation density not exceeding 104/cm2 and considerably lower compared to the dislocation density of the seed, and having a large curvature radius of the crystalline lattice, preferably longer than 15 m, more preferably longer than 30 m, and most preferably of about 70 m, considerably longer than the curvature radius of the crystalline lattice of the seed.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: March 19, 2013
    Assignees: Ammono S.A., Nichia Corporation
    Inventors: Robert Dwilinski, Roman Doradzinski, Jerzy Garczynski, Leszek Sierzputowski, Yasuo Kanbara, Robert Kucharski
  • Patent number: 8383494
    Abstract: Disclosed is a method for forming a buffer layer for growing gallium nitride single crystals on a sapphire substrate using hydride vapor phase epitaxy (HVPE), wherein the buffer layer is formed in the form of a doped vertical gallium nitride (GaN) single crystal film with a nanoporosity of 0.10 to 0.15 ?m on the sapphire substrate by reacting HCl and NH3 as a Group III/V mix gas. The nanoporous buffer layer interposed on the interface between the sapphire substrate and gallium nitride reduces tensile stress generated by the difference in thermal expansion coefficient between gallium nitride and the sapphire substrate, enables growth of the gallium nitride layer to a thickness of 1 micrometer (?m) to several millimeters (mm) without causing cracks, and reduces the lattice constant difference to improve crystallinity.
    Type: Grant
    Filed: May 1, 2009
    Date of Patent: February 26, 2013
    Assignee: Grand Tech Co., Ltd
    Inventors: Kyung Seob Han, Jeong Heo, Hyeong Jun Kim, Seung Kil Lee
  • Patent number: 8349742
    Abstract: A gallium nitride-based semiconductor device includes a composite substrate and a gallium nitride layer. The composite substrate includes a silicon substrate and a filler. The silicon substrate includes a first surface and a second surface opposite to the first surface, and the first surface defines a number of grooves therein. The filler is filled into the number of grooves on the first surface of the silicon substrate. A thermal expansion coefficient of the filler is bigger than that of the silicon substrate. The gallium nitride layer is formed on the second surface of the silicon substrate.
    Type: Grant
    Filed: January 26, 2011
    Date of Patent: January 8, 2013
    Assignee: Advanced Optoelectronic Technology, Inc.
    Inventors: Po-Min Tu, Shih-Cheng Huang, Shun-Kuei Yang, Chia-Hung Huang
  • Patent number: 8349076
    Abstract: A method of fabricating a freestanding gallium nitride (GaN) substrate includes: preparing a GaN substrate within a reactor; supplying HCl and NH3 gases into the reactor to treat the surface of the GaN substrate and forming a porous GaN layer; forming a GaN crystal growth layer on the porous GaN layer; and cooling the GaN substrate on which the GaN crystal growth layer has been formed and separating the GaN crystal growth layer from the substrate. According to the fabrication method, the entire process including forming a porous GaN layer and a thick GaN layer is performed in-situ within a single reactor. The method is significantly simplified compared to a conventional fabrication method. The fabrication method enables the entire process to be performed in one chamber while allowing GaN surface treatment and growth to be performed using HVPE process gases, thus resulting in a significant reduction in manufacturing costs.
    Type: Grant
    Filed: October 11, 2006
    Date of Patent: January 8, 2013
    Assignee: Samsung Corning Precision Materials Co., Ltd.
    Inventors: In-Jae Song, Jai-yong Han
  • Patent number: 8349077
    Abstract: Reducing the microvoid (MV) density in AlN ameliorates numerous problems related to cracking during crystal growth, etch pit generation during the polishing, reduction of the optical transparency in an AlN wafer, and, possibly, growth pit formation during epitaxial growth of AlN and/or AlGaN. This facilitates practical crystal production strategies and the formation of large, bulk AlN crystals with low defect densities—e.g., a dislocation density below 104 cm?2 and an inclusion density below 104 cm?3 and/or a MV density below 104 cm?3.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: January 8, 2013
    Assignee: Crystal IS, Inc.
    Inventors: Robert T. Bondokov, Kenneth Morgan, Glen A. Slack, Leo J. Schowalter
  • Patent number: 8337614
    Abstract: The surface of a gallium nitride single crystal substrate is processed, e.g., comprising steps by planarizing the top side and the bottom side of a gallium nitride original substrate positioned on a support bed; radiating light having wavelengths ranging from 370 to 800 nanometers (nm) onto the planarized gallium nitride original substrate; measuring transmittance of the gallium nitride original substrate; and confirming whether the transmittance is within the range of 65 to 90%. A gallium nitride single crystal substrate obtained through the method of processing the surface has high transmittance ranging from 65 to 90% measured using light having wavelengths of 370 to 800 nm. The thickness ratio (DLa/DLb) of the damage layers on the both sides of the gallium nitride single crystal substrate can be obtained within the range of 0.99 to 1.01.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: December 25, 2012
    Assignee: Samsung Corning Precision Materials Co., Ltd.
    Inventors: Jin Suk Jeong, Ki Soo Lee, Kyoung Jun Kim, Ju Heon Lee, Chang Uk Jin
  • Patent number: 8337617
    Abstract: A method for manufacturing a group III nitride crystal on a seed crystal in a holding vessel holding therein a melt containing a group III metal, an alkali metal and nitrogen. The manufacturing method comprises the steps of causing the seed crystal to make a contact with the melt, setting an environment of the seed crystal to a first state offset from a crystal growth condition while in a state in which said seed crystal is in contact with the melt, increasing a nitrogen concentration in the melt, and setting the environment of the seed crystal to a second state suitable for crystal growth when the nitrogen concentration of the melt has reached a concentration suitable for growing the seed crystal.
    Type: Grant
    Filed: March 13, 2006
    Date of Patent: December 25, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Hirokazu Iwata, Seiji Sarayama, Minoru Fukuda, Tetsuya Takahashi, Akira Takahashi
  • Patent number: 8323405
    Abstract: An apparatus and associated method for large-scale manufacturing of gallium nitride is provided. The apparatus comprises a large diameter autoclave and a raw material basket. Methods include metered addition of dopants in the raw material and control of the atmosphere during crystal growth. The apparatus and methods are scalable up to very large volumes and are cost effective.
    Type: Grant
    Filed: August 3, 2009
    Date of Patent: December 4, 2012
    Assignee: Soraa, Inc.
    Inventor: Mark P. D'Evelyn
  • Patent number: 8262794
    Abstract: A method is provided of growing crystals from compounds that melt congruently with negligible volatilization. The composition of one or more crystal samples is measured. A determination is made of a deviation of crystal composition from congruency. A determination is made of an initial melt composition and a source material composition correction relative to the deviation. Crystals are grown using the composition correction to yield reproducible material for surface acoustic substrate manufacturing.
    Type: Grant
    Filed: March 20, 2009
    Date of Patent: September 11, 2012
    Assignee: Crystal Technology, Inc.
    Inventors: Dieter Hans Jundt, Maria Claudia Custodio Kajiyama, John Thomas Carella
  • Patent number: 8258051
    Abstract: The present III-nitride crystal manufacturing method, a method of manufacturing a III-nitride crystal (20) having a major surface (20m) of plane orientation other than {0001}, designated by choice, includes: a step of slicing III-nitride bulk crystal (1) into a plurality of III-nitride crystal substrates (10p), (10q) having major surfaces (10pm), (10qm) of the designated plane orientation; a step of disposing the substrates (10p), (10q) adjoining each other sideways in such a way that the major surfaces (10pm), (10qm) of the substrates (10p), (10q) parallel each other and so that the [0001] directions in the substrates (10p), (10q) are oriented in the same way; and a step of growing III-nitride crystal (20) onto the major surfaces (10pm), (10qm) of the substrates (10p), (10q).
    Type: Grant
    Filed: May 17, 2009
    Date of Patent: September 4, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Naho Mizuhara, Koji Uematsu, Michimasa Miyanaga, Keisuke Tanizaki, Hideaki Nakahata, Seiji Nakahata, Takuji Okahisa
  • Patent number: 8258603
    Abstract: A solid-state far ultraviolet light emitting element is formed by a hexagonal boron nitride single crystal, excited by electron beam irradiation to emit far ultraviolet light having a maximum light emission peak in a far ultraviolet region at a wavelength of 235 nm or shorter.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: September 4, 2012
    Assignee: National Institute for Materials Science
    Inventors: Kenji Watanabe, Takashi Taniguchi, Satoshi Koizumi, Hisao Kanda, Masayuki Katagiri, Takatoshi Yamada, Nesladek Milos
  • Patent number: 8236103
    Abstract: A method for producing a Group III nitride semiconductor crystal includes a first step of supplying a Group III raw material and a Group V raw material at a V/III ratio of 0 to 1,000 to form and grow a Group III nitride semiconductor on a heated substrate and a second step of vapor-phase-growing a Group III nitride semiconductor crystal on the substrate using a Group III raw material and a nitrogen raw material.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: August 7, 2012
    Assignee: Showa Denko K.K.
    Inventors: Hisayuki Miki, Tetsuo Sakurai, Mineo Okuyama