Patents Assigned to Nichia Chemical Industries, Ltd.
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Patent number: 6469323Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure. The double-heterostructure includes a light-emitting layer formed of a low-resistivity InxGa1−xN (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: March 1, 2000Date of Patent: October 22, 2002Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Publication number: 20020046693Abstract: A method of growing a nitride semiconductor crystal which has very few crystal defects and can be used as a substrate is disclosed. This invention includes the step of forming a first selective growth mask on a support member including a dissimilar substrate having a major surface and made of a material different from a nitride semiconductor, the first selective growth mask having a plurality of first windows for selectively exposing the upper surface of the support member, and the step of growing nitride semiconductor portions from the upper surface, of the support member, which is exposed from the windows, by using a gaseous Group 3 element source and a gaseous nitrogen source, until the nitride semiconductor portions grown in the adjacent windows combine with each other on the upper surface of the selective growth mask.Type: ApplicationFiled: November 8, 2001Publication date: April 25, 2002Applicant: NICHIA CHEMICAL INDUSTRIES, LTD.Inventors: Hiroyuki Kiyoku, Shuji Nakamura, Tokuya Kozaki, Naruhito Iwasa, Kazuyuki Chocho
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Patent number: 6334908Abstract: A magnetic powder of an Sm—Fe—N alloy, which has a mean particle diameter of 0.5 to 10 &mgr;m, and either an average acicularity of 75% or above or an average sphericity of 78% or above. The powder exhibits an extremely high residual magnetization and an extremely high coercive force, since particles characterized by the above acicularity or sphericity have particle diameters approximately equal to that of the single domain particle and nearly spherical particle shapes. The powder can be produced by preparing an Sm—Fe oxide by firing a coprecipitate corresponding to the oxide, mixing the obtained oxide with metallic calcium and subjecting the mixture to reduction/diffusion and nitriding successively.Type: GrantFiled: June 23, 2000Date of Patent: January 1, 2002Assignee: Nichia Chemical Industries, Ltd.Inventors: Yohsiyuki Kawano, Michiya Kume, Keiji Ichinomiya
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Publication number: 20010022367Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate, and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: ApplicationFiled: January 2, 2001Publication date: September 20, 2001Applicant: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando
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Patent number: 6215133Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure. The double-heterostructure includes a light-emitting layer formed of a low-resistivity InxGa1-xN (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: April 28, 1999Date of Patent: April 10, 2001Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Patent number: 6204512Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate, and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: GrantFiled: November 24, 1999Date of Patent: March 20, 2001Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando
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Patent number: 6172382Abstract: A nitride semiconductor device including a light emitting device comprises a n-type region of one or more nitride semiconductor layers having n-type conductivity, a p-type region of one or more nitride semiconductor layers having p-type conductivity and an active layer between the n-type region and the p-type region. In such devices, there is provided with a super lattice layer comprising first layers and second layers which are nitride semiconductors having a different composition respectively. The super lattice structure makes working current and voltage of the device lowered, resulting in realization of more efficient devices.Type: GrantFiled: January 9, 1998Date of Patent: January 9, 2001Assignee: Nichia Chemical Industries, Ltd.Inventors: Shinichi Nagahama, Masayuki Senoh, Shuji Nakamura
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Patent number: 6153010Abstract: A method of growing a nitride semiconductor crystal which has very few crystal defects and can be used as a substrate is disclosed. This invention includes the step of forming a first selective growth mask on a support member including a dissimilar substrate having a major surface and made of a material different from a nitride semiconductor, the first selective growth mask having a plurality of first windows for selectively exposing the upper surface of the support member, and the step of growing nitride semiconductor portions from the upper surface, of the support member, which is exposed from the windows, by using a gaseous Group 3 element source and a gaseous nitrogen source, until the nitride semiconductor portions grown in the adjacent windows combine with each other on the upper surface of the selective growth mask.Type: GrantFiled: December 9, 1998Date of Patent: November 28, 2000Assignee: Nichia Chemical Industries Ltd.Inventors: Hiroyuki Kiyoku, Shuji Nakamura, Tokuya Kozaki, Naruhito Iwasa, Kazuyuki Chocho
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Patent number: 6093965Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate, and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: GrantFiled: December 11, 1998Date of Patent: July 25, 2000Assignee: Nichia Chemical Industries Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando
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Patent number: 6078063Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure. The double-heterostructure includes a light-emitting layer formed of a low-resistivity In.sub.x Ga.sub.1-x N (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: September 3, 1998Date of Patent: June 20, 2000Assignee: Nichia Chemical Industries Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Patent number: 5959307Abstract: A nitride semiconductor device has a nitride semiconductor layer structure. The structure includes an active layer of a quantum well structure containing an indium-containing nitride semiconductor. A first nitride semiconductor layer having a band gap energy larger than that of the active layer is provided in contact with the active layer. A second nitride semiconductor layer having a band gap energy smaller than that of the first layer is provided over the first layer. Further, a third nitride semiconductor layer having a band gap energy larger than that of the second layer is provided over the second layer.Type: GrantFiled: November 6, 1996Date of Patent: September 28, 1999Assignee: Nichia Chemical Industries Ltd.Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa
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Patent number: 5880486Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure. The double-heterostructure includes a light-emitting layer formed of a low-resistivity In.sub.x Ga.sub.1-x N (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: August 30, 1996Date of Patent: March 9, 1999Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Patent number: 5877558Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate, and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: GrantFiled: December 19, 1997Date of Patent: March 2, 1999Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando
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Patent number: 5861713Abstract: On manufacturing a low voltage electron beam excitation phosphor display apparatus (10) which includes an anode (6) having a principal surface and enclosed in a vacuum chamber (1, 2, and 3), a phosphor film (7) formed on the principal surface, and a cathode (9) enclosed in the vacuum chamber opposite to the phosphor film, a phosphor is prepared which consists essentially of an oxisulfide and an oxide which is inevitably formed on a surface of the oxisulfide on preparing the phosphor. The oxisulfide is represented by Ln.sub.2 O.sub.2 S:R, where Ln is at least one selected from a group consisting of Gd, La, Y, and Lu and where R is a rare-earth element. The oxide is removed from the phosphor to produce an oxide-removed phosphor. A pasts comprising a mixture of the oxide-removed phosphor, a conductive material, and an autolytic type binder is coated on the principal surface of the anode which is formed on an insulating substrate (1) constituting the vacuum chamber.Type: GrantFiled: June 26, 1997Date of Patent: January 19, 1999Assignees: NEC Corporation, Nichia Chemical Industries, LTD.Inventors: Yojiro Kondo, Toshihiko Ayusawa, Hidehito Mori, Osamu Yamasita, Kazuo Kaneko, Masayuki Usui, Yosinori Hirai, Masato Hayashi, Yasuhiro Mano, Masaki Mori, Kenichi Ishidate, Katsunori Uchimura
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Patent number: 5859496Abstract: An afterglow lamp has a light emitting section for converting electric energy to optical energy. A fluorescent layer is excited to emit-light by the light emitting section and is represented by the general formula (M.sub.1-p-q, Eu.sub.p Q.sub.q)O.multidot.n(Al.sub.1-m B.sub.m).sub.2 O.sub.3 .multidot.kP .sub.2 O.sub.5 .multidot..alpha.X. The values of p, q, n, m, k, .alpha. and .alpha./n are in the ranges 0.0001.ltoreq.p.ltoreq.0.5, 0.0001.ltoreq.q.ltoreq.0.5, 0.5.ltoreq.n.ltoreq.3.0, O.ltoreq.m.ltoreq.0.5, O.ltoreq.k.ltoreq.0.2, O.ltoreq..alpha..ltoreq.0.5, and O.ltoreq..alpha./n.ltoreq.0.4. M is at least one selected from a group of divalent metals including Mg; Q is a coactivator and at least one selected from a group including Mn, Zr, Nb, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and X is at least one selected from halogen elements.Type: GrantFiled: May 10, 1996Date of Patent: January 12, 1999Assignee: Nichia Chemical Industries, Ltd.Inventors: Yoshinori Murazaki, Keiji Ichinomiya
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Patent number: 5777350Abstract: A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.Type: GrantFiled: November 30, 1995Date of Patent: July 7, 1998Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa, Hiroyuki Kiyoku
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Patent number: 5767581Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: GrantFiled: June 17, 1996Date of Patent: June 16, 1998Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando
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Patent number: 5747832Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure. The double-heterostructure includes a light-emitting layer formed of a low-resistivity In.sub.x Ga.sub.1-x N (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: June 10, 1996Date of Patent: May 5, 1998Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Patent number: 5734182Abstract: A light-emitting gallium nitride-based compound semiconductor device of a double-heterostructure is disclosed. The double-heterostructure includes a light-emitting layer formed of a low-resistivity In.sub.x Ga.sub.1-x N (0<x<1) compound semiconductor doped with p-type and/or n-type impurity. A first clad layer is joined to one surface of the light-emitting layer and formed of an n-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer. A second clad layer is joined to another surface of the light-emitting layer and formed of a low-resistivity, p-type gallium nitride-based compound semiconductor having a composition different from the light-emitting layer.Type: GrantFiled: June 10, 1996Date of Patent: March 31, 1998Assignee: Nichia Chemical Industries Ltd.Inventors: Shuji Nakamura, Takashi Mukai, Naruhito Iwasa
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Patent number: 5652434Abstract: A gallium nitride-based III-V Group compound semiconductor device has a gallium nitride-based III-V Group compound semiconductor layer provided over a substrate, and an ohmic electrode provided in contact with the semiconductor layer. The ohmic electrode is formed of a metallic material, and has been annealed.Type: GrantFiled: June 17, 1996Date of Patent: July 29, 1997Assignee: Nichia Chemical Industries, Ltd.Inventors: Shuji Nakamura, Takao Yamada, Masayuki Senoh, Motokazu Yamada, Kanji Bando