Patents by Inventor Atsushi Ohido
Atsushi Ohido has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11773508Abstract: A substrate 10 comprises: a first layer L1 containing crystalline aluminum nitride; a second layer L2 containing crystalline ?-alumina; and an intermediate layer Lm sandwiched between the first layer L1 and the second layer L2 and containing aluminum, nitrogen, and oxygen, and the content of nitrogen in the intermediate layer Lm decreases in a direction Z from the first layer L1 toward the second layer L2, and the content of oxygen in the intermediate layer Lm increases in the direction Z from the first layer L1 toward the second layer L2.Type: GrantFiled: August 21, 2018Date of Patent: October 3, 2023Assignee: TDK CorporationInventors: Atsushi Ohido, Kazuhito Yamasawa, Katsumi Kawasaki
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Publication number: 20220158029Abstract: A substrate 10 contains a first layer L1 and a second layer L2 that are stacked on one another, the first layer L1 contains crystalline AlN and an additive element, the second layer L2 contains crystalline ?-alumina, the additive element is at least one selected from the group consisting of rare earth elements, alkaline earth elements, and alkali metal elements, the thickness of the first layer L1 is 5 to 600 nm, RC(002) is a rocking curve of diffracted X-rays originating from a (002) plane of AlN, RC(002) is measured by an ?-scan of the surface SL1 of the first layer L1, the half width of RC(002) is 0° to 0.4°, RC(100) is a rocking curve of diffracted X-rays originating from a (100) plane of AlN, RC(100) is measured by a ?-scan of the surface SL1 of the first layer L1, and the half width of RC(100) is 0° to 0.8°.Type: ApplicationFiled: February 27, 2020Publication date: May 19, 2022Applicant: TDK CorporationInventors: Atsushi OHIDO, Kazuhito YAMASAWA
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Publication number: 20200283928Abstract: A substrate 10 comprises: a first layer L1 containing crystalline aluminum nitride; a second layer L2 containing crystalline ?-alumina; and an intermediate layer Lm sandwiched between the first layer L1 and the second layer L2 and containing aluminum, nitrogen, and oxygen, and the content of nitrogen in the intermediate layer Lm decreases in a direction Z from the first layer L1 toward the second layer L2, and the content of oxygen in the intermediate layer Lm increases in the direction Z from the first layer L1 toward the second layer L2.Type: ApplicationFiled: August 21, 2018Publication date: September 10, 2020Applicant: TDK CorporationInventors: Atsushi OHIDO, Kazuhito YAMASAWA, Katsumi KAWASAKI
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Publication number: 20200109488Abstract: A nitride single crystal having high crystallinity is provided. A nitride single crystal 10 has a wurtzite crystal structure, and a content of boron is 0.5 ppm by mass or more and 251 ppm by mass or less.Type: ApplicationFiled: March 22, 2018Publication date: April 9, 2020Applicant: TDK CorporationInventors: Atsushi OHIDO, Katsumi KAWASAKI, Kazuhito YAMASAWA
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Patent number: 10458041Abstract: An alumina substrate on which an AlN layer is formed and that causes less warping, and a substrate material strong enough to withstand normal handling when an AlN crystal is grown upon it, and prevents cracking and fracturing of a grown crystal when stress is applied during growing or cooling. The substrate has a gap and a rare earth element-containing region inside the AlN layer or at the interface between the AlN layer and the alumina substrate. Warping of the AlN layer can be reduced by lattice-mismatch stress being concentrated at the region and releasing of stress by the gap. The region having a concentrating of stress, and the gap having a low mechanical strength, can induce crackings and fracturings. As a result, contamination of crackings and fracturings into the crystal grown on the substrate can be prevented. The region can ensure a level of mechanical strength sufficient for handling.Type: GrantFiled: March 2, 2016Date of Patent: October 29, 2019Assignee: TDK CORPORATIONInventors: Kazuhito Yamasawa, Atsushi Ohido, Katsumi Kawasaki
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Patent number: 10337120Abstract: An alumina substrate having a carbon-containing phase with an AlN layer formed on a surface of the alumina substrate.Type: GrantFiled: August 6, 2015Date of Patent: July 2, 2019Assignee: TDK CORPORATIONInventors: Kazuhito Yamasawa, Atsushi Ohido, Katsumi Kawasaki
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Patent number: 10294585Abstract: An alumina substrate wherein an AlN layer is formed on a surface of the alumina substrate and a rare earth elements-containing layer and/or rare earth elements-containing regions is/are formed in the interior of the AlN layer or in the interface between the AlN layer and the alumina substrate.Type: GrantFiled: August 6, 2015Date of Patent: May 21, 2019Assignee: TDK CORPORATIONInventors: Kazuhito Yamasawa, Atsushi Ohido, Katsumi Kawasaki
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Publication number: 20180038011Abstract: An alumina substrate on which an AlN layer is formed and that causes less warping, and a substrate material strong enough to withstand normal handling when an AlN crystal is grown upon it, and prevents cracking and fracturing of a grown crystal when stress is applied during growing or cooling. The substrate has a gap and a rare earth element-containing region inside the AlN layer or at the interface between the AlN layer and the alumina substrate. Warping of the AlN layer can be reduced by lattice-mismatch stress being concentrated at the region and releasing of stress by the gap. The region having a concentrating of stress, and the gap having a low mechanical strength, can induce crackings and fracturings. As a result, contamination of crackings and fracturings into the crystal grown on the substrate can be prevented. The region can ensure a level of mechanical strength sufficient for handling.Type: ApplicationFiled: March 2, 2016Publication date: February 8, 2018Applicant: TDK CORPORATIONInventors: Kazuhito YAMASAWA, Atsushi OHIDO, Katsumi KAWASAKI
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Publication number: 20170218535Abstract: An alumina substrate having a carbon-containing phase with an AlN layer formed on a surface of the alumina substrate.Type: ApplicationFiled: August 6, 2015Publication date: August 3, 2017Applicant: TDK CORPORATIONInventors: Kazuhito YAMASAWA, Atsushi OHIDO, Katsumi KAWASAKI
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Publication number: 20170211204Abstract: An alumina substrate wherein an AlN layer is formed on a surface of the alumina substrate and a rare earth elements-containing layer and/or rare earth elements-containing regions is/are formed in the interior of the AlN layer or in the interface between the AlN layer and the alumina substrate.Type: ApplicationFiled: August 6, 2015Publication date: July 27, 2017Applicant: TDK CORPORATIONInventors: Kazuhito YAMASAWA, Atsushi OHIDO, Katsumi KAWASAKI
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Patent number: 8815011Abstract: The present invention relates to a magnetic garnet single crystal prepared by the liquid phase epitaxial (LPE) process and an optical element using the same as well as a method of producing the single crystal, for the purpose of providing a magnetic garnet single crystal at a reduced Pb content and an optical element using the same, as well as a method of producing the single crystal. The magnetic garnet single crystal is grown by the liquid phase epitaxial process and is represented by the chemical formula BixNayPbzM13-x-y-zFe5-wM2wO12 (M1 is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M2 is at least one element selected from Ga, Al, In, Ti, Ge, Si and Pt, provided that 0.5<x?2.0, 0<y?0.8, 0?z<0.01, 0.19?3-x-y-z<2.5, and 0?w?1.6).Type: GrantFiled: August 27, 2010Date of Patent: August 26, 2014Assignee: TDK CorporationInventor: Atsushi Ohido
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Patent number: 8142676Abstract: The invention relates to a magnetic garnet single crystal and an optical element using the same, for the purpose of providing a magnetic garnet single crystal at a reduced Pb content, and an optical element using the same, where the magnetic garnet single crystal is represented by the chemical formula Bi?M13-?Fe5-?-?M2?M3?O12 (M1 is at least one element selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M2 is Si; and M3 is at least one element selected from Zn, Ni, Cu and Mg, provided that 0.5<??2.0, 0<?, and 0<y).Type: GrantFiled: February 9, 2007Date of Patent: March 27, 2012Assignee: TDK CorporationInventor: Atsushi Ohido
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Publication number: 20100326350Abstract: The present invention relates to a magnetic garnet single crystal prepared by the liquid phase epitaxial (LPE) process and an optical element using the same as well as a method of producing the single crystal, for the purpose of providing a magnetic garnet single crystal at a reduced Pb content and an optical element using the same, as well as a method of producing the single crystal. The magnetic garnet single crystal is grown by the liquid phase epitaxial process and is represented by the chemical formula BixNayPbzM13-x-y-zFe5-wM2wO12 (M1 is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M2 is at least one element selected from Ga, Al, In, Ti, Ge, Si and Pt, provided that 0.5<x?2.0, 0<y?0.8, 0?z<0.01, 0.19?3-x-y-z<2.5, and 0?w?1.6).Type: ApplicationFiled: August 27, 2010Publication date: December 30, 2010Applicant: TDK CORPORATIONInventor: Atsushi Ohido
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Patent number: 7828895Abstract: The invention relates to a method of producing an optical element using a garnet single crystal for the purpose of providing an optical element with a reduced Pb content or from which Pb can preliminarily be removed completely. By growing a garnet single crystal by using a solution containing Na, Bi and B by the LPE process and thermally treating the garnet single crystal in reducing atmosphere prepared by using nitrogen gas and/or hydrogen gas, the resulting thermally treated garnet single crystal is used to prepare an optical element.Type: GrantFiled: January 19, 2007Date of Patent: November 9, 2010Assignee: TDK CorporationInventor: Atsushi Ohido
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Patent number: 7811465Abstract: The present invention relates to a magnetic garnet single crystal prepared by the liquid phase epitaxial (LPE) process and an optical element using the same as well as a method of producing the single crystal, for the purpose of providing a magnetic garnet single crystal at a reduced Pb content and an optical element using the same, as well as a method of producing the single crystal. The magnetic garnet single crystal is grown by the liquid phase epitaxial process and is represented by the chemical formula BixNayPbzM13?x?y?zFe5?wM2wO12 (M1 is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M2 is at least one element selected from Ga, Al, In, Ti, Ge, Si and Pt, provided that 0.5<x?2.0, 0<y?0.8, 0?z<0.01, 0.19?3?x?y?z<2.5, and 0?w?1.6).Type: GrantFiled: November 17, 2005Date of Patent: October 12, 2010Assignee: TDK CorporationInventor: Atsushi Ohido
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Patent number: 7758766Abstract: It is an object of the present invention to provide a magnetic garnet single crystal capable of reducing the optical loss of the resulting rotator even when the magnetic garnet single crystal is grown using a solvent containing Na by the liquid phase epitaxial process, as well as a Faraday rotator using the same. A magnetic garnet single crystal represented by the chemical formula Bi?Na?M13-?-?-?M2?Fe5-?-?Mg?M3?O12 (M1 is at least one element or more selected from Y, Eu, Gd, Tb, Dy, Ho, Yb and Lu; and M2 is at least one element or more selected from Ca and Sr; M3 is at least one element or more selected from Si, Ge, Ti, Pt, Ru, Sn, Hf and Zr, provided that 0.60<??1.50, 0<??0.05, 1.35<3??????<2.40, 0???0.10, 0???0.10, 0<??0.10, 0<?+??0.10, 0<?+??0.10).Type: GrantFiled: September 17, 2007Date of Patent: July 20, 2010Assignee: TDK CorporationInventor: Atsushi Ohido
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Patent number: 7695562Abstract: It is an object of the present invention to provide a magnetic garnet single crystal at a reduced Pb content, and a method for producing the same and an optical element using the same. The object is attained with a magnetic garnet single crystal represented by the chemical formula Bi?Na?M13-?-?Fe5-?M2?O12 (M1 is at least one element selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M2 is at least one element selected from Si, Ge and Ti, provided that 0.5<??2.0, 0<??0.8, 0.2?3????<2.5, and 0<??1.6).Type: GrantFiled: December 29, 2006Date of Patent: April 13, 2010Assignee: TDK CorporationInventor: Atsushi Ohido
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Patent number: 7517406Abstract: Proposed is a technique of producing a magnetic garnet material of which the light absorption characteristics worsen little even though it is produced through LPE. The crucible for LPE is formed of a material containing Au. The amount of Au to be taken in single crystal formed in an Au crucible is smaller than that of Pt to be taken therein formed in a Pt crucible. As compared with Pt, the influence of Au on magnetic garnet film that increases the insertion loss in the film is small.Type: GrantFiled: December 21, 2007Date of Patent: April 14, 2009Assignee: TDK CorporationInventors: Atsushi Ohido, Tamotsu Sugawara, Kazuhito Yamasawa, Shinichiro Kakei, Kazuya Shimakawa, Katsunori Hosoya
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Publication number: 20090073549Abstract: It is an object of the present invention to provide a magnetic garnet single crystal capable of reducing the optical loss of the resulting rotator even when the magnetic garnet single crystal is grown using a solvent containing Na by the liquid phase epitaxial process, as well as a Faraday rotator using the same. A magnetic garnet single crystal represented by the chemical formula Bi?Na?M13-?-?-?M2?Fe5-?-?Mg?M3?O12 (M1 is at least one element or more selected from Y, Eu, Gd, Tb, Dy, Ho, Yb and Lu; and M2 is at least one element or more selected from Ca and Sr; M3 is at least one element or more selected from Si, Ge, Ti, Pt, Ru, Sn, Hf and Zr, provided that 0.60<??1.50, 0<??0.05, 1.35<3??????<2.40, 0???0.10, 0???0.10, 0<??0.10, 0<?+??0.10, 0<?+??0.10).Type: ApplicationFiled: September 17, 2007Publication date: March 19, 2009Applicant: TDK CORPORATIONInventor: Atsushi Ohido
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Publication number: 20080112046Abstract: Proposed is a technique of producing a magnetic garnet material of which the light absorption characteristics worsen little even though it is produced through LPE. The crucible for LPE is formed of a material containing Au. The amount of Au to be taken in single crystal formed in an Au crucible is smaller than that of Pt to be taken therein formed in a Pt crucible. As compared with Pt, the influence of Au on magnetic garnet film that increases the insertion loss in the film is small.Type: ApplicationFiled: December 21, 2007Publication date: May 15, 2008Applicant: TDK CorporationInventors: Atsushi Ohido, Tamotsu Sugawara, Kazuhito Yamasawa, Shinichiro Kakei, Kazuya Shimakawa, Katsunori Hosoya