Patents by Inventor Kenji Noma
Kenji Noma 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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Publication number: 20200075671Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer having a variable magnetization direction, and including a first main surface and a second main surface located opposite to the first main surface, a second magnetic layer provided on a first main surface side of the first magnetic layer, and having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, wherein a saturation magnetization of a part of the first magnetic layer which is located close to the first main surface is higher than a saturation magnetization of a part of the first magnetic layer which is located close to the second main surface.Type: ApplicationFiled: November 8, 2019Publication date: March 5, 2020Applicant: TOSHIBA MEMORY CORPORATIONInventors: Jyunichi OZEKI, Masahiko NAKAYAMA, Hiroaki YODA, Eiji KITAGAWA, Takao OCHIAI, Minoru AMANO, Kenji NOMA
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Patent number: 10388855Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer having a variable magnetization direction, a nonmagnetic layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic layer and having a fixed magnetization direction, wherein as viewed in a direction parallel to a stacked direction of the stacked structure, a pattern of a lower surface of the first magnetic layer is located inside a pattern of an upper surface of the first magnetic layer, and a pattern of an upper surface of the second magnetic layer is located inside a pattern of a lower surface of the second magnetic layer or substantially conforms to the pattern of the lower surface of the second magnetic layer.Type: GrantFiled: August 30, 2017Date of Patent: August 20, 2019Assignee: TOSHIBA MEMORY CORPORATIONInventors: Shuichi Tsubata, Masatoshi Yoshikawa, Kenji Noma
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Patent number: 10236437Abstract: A magnetic memory device includes a semiconductor substrate; a magnetoresistive element provided on the semiconductor substrate. The magnetoresistive element includes a storage layer, a tunnel barrier layer, and a reference layer which are stacked, the reference layer having a magnetization direction perpendicular to a principal surface of the semiconductor substrate. The magnetic memory device further includes a magnetic field generation section provided away from the magnetoresistive element and configured to generate a magnetic field perpendicular to the principal surface of the semiconductor substrate. The semiconductor substrate, the magnetoresistive element and the magnetic field generation section are integrated as one unit.Type: GrantFiled: July 15, 2016Date of Patent: March 19, 2019Assignee: TOSHIBA MEMORY CORPORATIONInventor: Kenji Noma
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Patent number: 10193057Abstract: A magnetic memory device includes a stacked structure including a magnetic element, a protective insulating film covering the stacked structure, and an interface layer provided at an interface between the stacked structure and the protective insulating film. The interface layer contains a predetermined element which is not contained in the magnetic element or the protective insulating film.Type: GrantFiled: January 6, 2017Date of Patent: January 29, 2019Assignee: TOSHIBA MEMORY CORPORATIONInventors: Masatoshi Yoshikawa, Hiroaki Yoda, Shuichi Tsubata, Kenji Noma, Tatsuya Kishi, Satoshi Seto, Kazuhiro Tomioka
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Publication number: 20190006580Abstract: A method of manufacturing a magnetic memory device includes forming a stacked structure including a magnetic element, forming a metal film which covers the stacked structure, and forming a protective insulating film formed of a metallic oxide by oxidizing the metal film. A metal element contained in the metallic oxide is selected from yttrium (Y), aluminum (Al), magnesium (Mg), calcium (Ca), zirconium (Zr) and hafnium (Hf).Type: ApplicationFiled: September 9, 2018Publication date: January 3, 2019Applicant: TOSHIBA MEMORY CORPORATIONInventors: Masatoshi YOSHIKAWA, Hiroaki YODA, Shuichi TSUBATA, Kenji NOMA, Tatsuya KISHI, Satoshi SETO, Kazuhiro TOMIOKA
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Publication number: 20180309048Abstract: A magnetoresistive effect element including a substrate; a pinned layer above the substrate; a free layer between the substrate and the pinned layer; a non-magnetic layer between the free layer and the pinned layer; a first layer provided on an opposite side of a side of the non-magnetic layer of the free layer, the first layer being between the substrate and the free layer, the first layer being in direct contact with the free layer, the first layer being non-magnetic and the first layer including a MgFeO layer, the MgFeO layer being an amorphous layer and being in direct contact with the free layer; and a second layer between the first layer and the substrate, the second layer being in contact with the substrate.Type: ApplicationFiled: June 19, 2018Publication date: October 25, 2018Applicant: TOSHIBA MEMORY CORPORATIONInventors: Takao Ochiai, Eiji Kitagawa, Kenji Noma
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Patent number: 10090062Abstract: A magnetic memory device includes a memory cell array comprising memory cells including magnetic tunnel junction elements. Each memory cell is electrically connected between a source line and a bit line. A control circuit is configured to perform a screening test on the memory cell array before writing data to the memory cell array. The screening test determines whether an abnormal cell is present in the memory cell array. The controller applies a first writing voltage to the write data to the memory cell array if the abnormal cell is not present, or applies a second writing voltage to write data to the memory cell array if the abnormal cell is present. The second writing voltage is different from the first writing voltage.Type: GrantFiled: June 12, 2017Date of Patent: October 2, 2018Assignee: TOSHIBA MEMORY CORPORATIONInventors: Shinya Kobayashi, Kenji Noma, Mikio Miyata
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Publication number: 20180269386Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer having a variable magnetization direction, a nonmagnetic layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic layer and having a fixed magnetization direction, wherein as viewed in a direction parallel to a stacked direction of the stacked structure, a pattern of a lower surface of the first magnetic layer is located inside a pattern of an upper surface of the first magnetic layer, and a pattern of an upper surface of the second magnetic layer is located inside a pattern of a lower surface of the second magnetic layer or substantially conforms to the pattern of the lower surface of the second magnetic layer.Type: ApplicationFiled: August 30, 2017Publication date: September 20, 2018Applicant: TOSHIBA MEMORY CORPORATIONInventors: Shuichi TSUBATA, Masatoshi YOSHIKAWA, Kenji NOMA
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Patent number: 10026888Abstract: According to one embodiment, a magnetoresistive effect element includes: a first magnetic layer; a second magnetic layer; a non-magnetic film between the first magnetic layer and the second magnetic layer; a first layer on an opposite side of a side of the non-magnetic layer of the first magnetic layer, the first layer including magnesium oxide as a principal component; and a second layer between the first film and the first magnetic layer, the second layer including a material different from a material of the first layer.Type: GrantFiled: March 5, 2015Date of Patent: July 17, 2018Assignee: TOSHIBA MEMORY CORPORATIONInventors: Takao Ochiai, Eiji Kitagawa, Kenji Noma
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Publication number: 20170365357Abstract: A magnetic memory device includes a memory cell array comprising memory cells including magnetic tunnel junction elements. Each memory cell is electrically connected between a source line and a bit line. A control circuit is configured to perform a screening test on the memory cell array before writing data to the memory cell array. The screening test determines whether an abnormal cell is present in the memory cell array. The controller applies a first writing voltage to the write data to the memory cell array if the abnormal cell is not present, or applies a second writing voltage to write data to the memory cell array if the abnormal cell is present. The second writing voltage is different from the first writing voltage.Type: ApplicationFiled: June 12, 2017Publication date: December 21, 2017Inventors: Shinya KOBAYASHI, Kenji NOMA, Mikio MIYATA
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Patent number: 9780298Abstract: According to one embodiment, a magnetoresistive element includes a recording layer having a variable magnetization direction, a reference layer having an invariable magnetization direction, an intermediate layer provided between the recording layer and the reference layer, and a first buffer layer provided on a surface of the recording layer, which is opposite to a surface of the recording layer where the intermediate layer is provided. The recording layer comprises a first magnetic layer which is provided in a side of the intermediate layer and contains CoFe as a main component, and a second magnetic layer which is provided in a side of the first buffer layer and contains CoFe as a main component, a concentration of Fe in the first magnetic layer being higher than a concentration of Fe in the second magnetic layer. The first buffer layer comprises a nitrogen compound.Type: GrantFiled: September 18, 2015Date of Patent: October 3, 2017Assignee: Kabushiki Kaisha ToshibaInventors: Eiji Kitagawa, Tadaomi Daibou, Tadashi Kai, Toshihiko Nagase, Kenji Noma, Hiroaki Yoda
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Publication number: 20170263679Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer having a variable magnetization direction, and including a first main surface and a second main surface located opposite to the first main surface, a second magnetic layer provided on a first main surface side of the first magnetic layer, and having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, wherein saturation magnetization of part of the first magnetic layer which is located close to the first main surface is higher than saturation magnetization of part of the first magnetic layer which is located close to the second main surface.Type: ApplicationFiled: September 16, 2016Publication date: September 14, 2017Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Jyunichi OZEKI, Masahiko NAKAYAMA, Hiroaki YODA, Eiji KITAGAWA, Takao OCHIAI, Minoru AMANO, Kenji NOMA
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Patent number: 9735347Abstract: According to one embodiment, a magnetic memory device includes: a first magnetic layer; a nonmagnetic layer on the first magnetic layer; a second magnetic layer on the nonmagnetic layer; and an insulator film on the nonmagnetic layer surrounding a side surface of the second magnetic layer. The second magnetic layer has an area of a surface facing the nonmagnetic layer smaller than that of the nonmagnetic layer. The nonmagnetic layer includes a first region that is provided between the first magnetic layer and the insulator film. The first region includes an amorphous state.Type: GrantFiled: March 9, 2016Date of Patent: August 15, 2017Assignee: KABUSHIKI KAISHA TOSHIBAInventors: Koji Yamakawa, Katsuaki Natori, Shinichi Kanoo, Kenji Noma
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Patent number: 9647034Abstract: According to one embodiment, a magnetoresistive memory device includes a stacked layer structure includes a first magnetic layer, a second magnetic layer, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer, and a third magnetic layer provided on the first magnetic layer, which is opposite the nonmagnetic layer. The third magnetic layer includes a first magnetic material portion and a second magnetic material portion provided between the stacked layer structure and the first magnetic material portion. The saturation magnetization of the second magnetic material portion is smaller than that of the first magnetic material portion.Type: GrantFiled: March 9, 2016Date of Patent: May 9, 2017Assignee: KABUSHIKI KAISHA TOSHIBAInventors: Masahiko Nakayama, Yutaka Hashimoto, Yasuyuki Sonoda, Tadashi Kai, Kenji Noma
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Publication number: 20170117454Abstract: A magnetic memory device includes a stacked structure including a magnetic element, a protective insulating film covering the stacked structure, and an interface layer provided at an interface between the stacked structure and the protective insulating film. The interface layer contains a predetermined element which is not contained in the magnetic element or the protective insulating film.Type: ApplicationFiled: January 6, 2017Publication date: April 27, 2017Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Masatoshi YOSHIKAWA, Hiroaki YODA, Shuichi TSUBATA, Kenji NOMA, Tatsuya KISHI, Satoshi SETO, Kazuhiro TOMIOKA
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Publication number: 20170069687Abstract: According to one embodiment, a magnetoresistive memory device includes a stacked layer structure includes a first magnetic layer, a second magnetic layer, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer, and a third magnetic layer provided on the first magnetic layer, which is opposite the nonmagnetic layer. The third magnetic layer includes a first magnetic material portion and a second magnetic material portion provided between the stacked layer structure and the first magnetic material portion. The saturation magnetization of the second magnetic material portion is smaller than that of the first magnetic material portion.Type: ApplicationFiled: March 9, 2016Publication date: March 9, 2017Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Masahiko NAKAYAMA, Yutaka HASHIMOTO, Yasuyuki SONODA, Tadashi KAI, Kenji NOMA
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Publication number: 20170062705Abstract: According to one embodiment, a magnetic memory device includes: a first magnetic layer; a nonmagnetic layer on the first magnetic layer; a second magnetic layer on the nonmagnetic layer; and an insulator film on the nonmagnetic layer surrounding a side surface of the second magnetic layer. The second magnetic layer has an area of a surface facing the nonmagnetic layer smaller than that of the nonmagnetic layer. The nonmagnetic layer includes a first region that is provided between the first magnetic layer and the insulator film. The first region includes an amorphous state.Type: ApplicationFiled: March 9, 2016Publication date: March 2, 2017Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Koji YAMAKAWA, Katsuaki NATORI, Shinichi KANOO, Kenji NOMA
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Publication number: 20170047085Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer having an invariable magnetization direction, a second magnetic layer having a variable magnetization direction, a first nonmagnetic layer between the first and second magnetic layers, a third magnetic layer having a variable magnetization direction, the magnetization directions of the second and third magnetic layers being opposite directions each other, and a second nonmagnetic layer between the second and third magnetic layers.Type: ApplicationFiled: March 4, 2016Publication date: February 16, 2017Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Kenji NOMA
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Patent number: 9570671Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a magnetic element, a protective insulating film covering the stacked structure, and an interface layer provided at an interface between the stacked structure and the protective insulating film. The interface layer contains a predetermined element which is not contained in the magnetic element or the protective insulating film.Type: GrantFiled: September 5, 2014Date of Patent: February 14, 2017Assignee: KABUSHIKI KAISHA TOSHIBAInventors: Masatoshi Yoshikawa, Hiroaki Yoda, Shuichi Tsubata, Kenji Noma, Tatsuya Kishi, Satoshi Seto, Kazuhiro Tomioka
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Publication number: 20160329487Abstract: A magnetic memory device includes a semiconductor substrate; a magnetoresistive element provided on the semiconductor substrate. The magnetoresistive element includes a storage layer, a tunnel barrier layer, and a reference layer which are stacked, the reference layer having a magnetization direction perpendicular to a principal surface of the semiconductor substrate. The magnetic memory device further includes a magnetic field generation section provided away from the magnetoresistive element and configured to generate a magnetic field perpendicular to the principal surface of the semiconductor substrate. The semiconductor substrate, the magnetoresistive element and the magnetic field generation section are integrated as one unit.Type: ApplicationFiled: July 15, 2016Publication date: November 10, 2016Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Kenji NOMA