Patents by Inventor Haruki Yokoyama
Haruki Yokoyama 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).
-
Patent number: 11967713Abstract: The present invention relates to a positive electrode active material for non-aqueous electrolyte secondary battery, including lithium-nickel composite oxide particles having a layer structure of hexagonal system; and a lithium tungstate coating film disposed on a surface of secondary particles of the lithium-nickel composite oxide particles, wherein the positive electrode active material for non-aqueous electrolyte secondary battery includes, as metallic elements, lithium (Li), nickel (Ni), cobalt (Co), element M (M) which is at least one element selected from Mn, V, Mg, Mo, Nb, Ti, Ca, Cr, Zr, Ta, and Al, and tungsten (W), wherein a ratio of amount of substance in the metallic elements contained is Li:Ni:Co:M:W=a:1-x-y:x:y:z, wherein 0.97?a?1.25, 0?x?0.35, 0?y?0.35, and 0.005?z?0.030.Type: GrantFiled: May 29, 2019Date of Patent: April 23, 2024Assignee: SUMITOMO METAL MINING CO., LTD.Inventors: Yuki Koshika, Haruki Kaneda, Jun Yokoyama
-
Patent number: 9006854Abstract: An APD is provided with the semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side, and a depletion control region that is provided in layers on the second mesa side relative to the p-type electric field control layer, formed in an encircling portion provided inside an outType: GrantFiled: September 1, 2011Date of Patent: April 14, 2015Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Tadao Ishibashi, Seigo Ando, Masahiro Nada, Yoshifumi Muramoto, Haruki Yokoyama
-
Patent number: 8754445Abstract: A layer in which the potential level difference normally unrequired for device operation is generated is positively inserted in a device structure. The potential level difference has such a function that even if a semiconductor having a small bandgap is exposed on a mesa side surface, a potential drop amount of the portion is suppressed, and a leakage current inconvenient for device operation can be reduced. This effect can be commonly obtained for a heterostructure bipolar transistor, a photodiode, an electroabsorption modulator, and so on. In the photodiode, since the leakage current is alleviated, the device size can be reduced, so that in addition to improvement of operating speed with a reduction in series resistance, it is advantageous that the device can be densely disposed in an array.Type: GrantFiled: January 20, 2012Date of Patent: June 17, 2014Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Toshihide Yoshimatsu, Haruki Yokoyama
-
Patent number: 8729602Abstract: An APD is provided with a semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side of the first mesa, and in the APD, a total donor concentration of the n-type electric field control layer is lower than a total acceptor concentration of the p-type electric field control layeType: GrantFiled: September 1, 2011Date of Patent: May 20, 2014Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Tadao Ishibashi, Seigo Ando, Masahiro Nada, Yoshifumi Muramoto, Haruki Yokoyama
-
Publication number: 20130313608Abstract: A layer in which the potential level difference normally unrequired for device operation is generated is positively inserted in a device structure. The potential level difference has such a function that even if a semiconductor having a small bandgap is exposed on a mesa side surface, a potential drop amount of the portion is suppressed, and a leakage current inconvenient for device operation can be reduced. This effect can be commonly obtained for a heterostructure bipolar transistor, a photodiode, an electroabsorption modulator, and so on. In the photodiode, since the leakage current is alleviated, the device size can be reduced, so that in addition to improvement of operating speed with a reduction in series resistance, it is advantageous that the device can be densely disposed in an array.Type: ApplicationFiled: January 20, 2012Publication date: November 28, 2013Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT ELECTRONICS CORPORATIONInventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Toshihide Yoshimatsu, Haruki Yokoyama
-
Patent number: 8575650Abstract: An electron injected APD with an embedded n electrode structure in which edge breakdown can be suppressed without controlling the doping profile of an n-type region of the embedded n electrode structure with high precision. The APD comprising a buffer layer with a low ionization rate is inserted between an n electrode connecting layer and an avalanche multiplication layer. Specifically, the APD is an electron injected APD in which an n electrode layer, the n electrode connecting layer, the buffer layer, the avalanche multiplication layer, an electric field control layer, a band gap gradient layer, a low-concentration light absorbing layer, a p-type light absorbing layer, and a p electrode layer are sequentially stacked, and a light absorbing portion that includes at least the low-concentration light absorbing layer and the p-type light absorbing layer forms a mesa shape.Type: GrantFiled: December 11, 2009Date of Patent: November 5, 2013Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone CorporationInventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Fumito Nakajima, Haruki Yokoyama
-
Publication number: 20130168793Abstract: An APD is provided with the semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side, and a depletion control region that is provided in layers on the second mesa side relative to the p-type electric field control layer, formed in an encircling portion provided inside an outType: ApplicationFiled: September 1, 2011Publication date: July 4, 2013Applicant: NTT ELECTRONICS CORPORATIONInventors: Tadao Ishibashi, Seigo Ando, Masahiro Nada, Yoshifumi Muramoto, Haruki Yokoyama
-
Publication number: 20130154045Abstract: An APD is provided with a semi-insulating substrate, a first mesa having a first laminate constitution in which a p-type electrode layer, a p-type light absorbing layer, a light absorbing layer with a low impurity concentration, a band gap inclined layer, a p-type electric field control layer, an avalanche multiplier layer, an n-type electric field control layer, and an electron transit layer with a low impurity concentration are stacked in this order on a surface of the semi-insulating substrate, a second mesa having an outer circumference provided inside an outer circumference of the first mesa as viewed from the laminating direction and having a second laminate constitution in which an n-type electrode buffer layer and an n-type electrode layer are stacked in this order on a surface on the electron transit layer side of the first mesa, and in the APD, a total donor concentration of the n-type electric field control layer is lower than a total acceptor concentration of the p-type electric field control layeType: ApplicationFiled: September 1, 2011Publication date: June 20, 2013Applicants: Nippon Telegraph and Telephone Corporation, NTT Electronics CorporationInventors: Tadao Ishibashi, Seigo Ando, Masahiro Nada, Yoshifumi Muramoto, Haruki Yokoyama
-
Publication number: 20110241150Abstract: An electron injected APD with an embedded n electrode structure in which edge breakdown can be suppressed without controlling the doping profile of an n-type region of the embedded n electrode structure with high precision. The APD comprising a buffer layer with a low ionization rate is inserted between an n electrode connecting layer and an avalanche multiplication layer. Specifically, the APD is an electron injected APD in which an n electrode layer, the n electrode connecting layer, the buffer layer, the avalanche multiplication layer, an electric field control layer, a band gap gradient layer, a low-concentration light absorbing layer, a p-type light absorbing layer, and a p electrode layer are sequentially stacked, and a light absorbing portion that includes at least the low-concentration light absorbing layer and the p-type light absorbing layer forms a mesa shape.Type: ApplicationFiled: December 11, 2009Publication date: October 6, 2011Inventors: Tadao Ishibashi, Seigo Ando, Yoshifumi Muramoto, Fumito Nakajima, Haruki Yokoyama
-
Patent number: 7242038Abstract: An n-type InP sub collector layer 2 heavily doped with silicon (Si), an InP collector layer 3, a p-type GaAs(0.51)Sb(0.49) base layer 4 heavily doped with carbon (C), an n-type In(1-y)Al(y)P emitter layer 7 doped with Si, an n-type InP cap layer 8 heavily doped with Si, and an n-type In(0.53)Ga(0.47)As contact layer 9 heavily doped with Si are stacked on a substrate 1.Type: GrantFiled: June 24, 2005Date of Patent: July 10, 2007Assignee: Nippon Telegraph and Telephone CorporationInventors: Yasuhiro Oda, Kenji Kurishima, Haruki Yokoyama, Takashi Kobayashi
-
Publication number: 20060231859Abstract: An n-type InP sub collector layer 2 heavily doped with silicon (Si), an InP collector layer 3, a p-type GaAs(0.51)Sb(0.49) base layer 4 heavily doped with carbon (C), an n-type In(1-y)Al(y)P emitter layer 7 doped with Si, an n-type InP cap layer 8 heavily doped with Si, and an n-type In(0.53)Ga(0.47)As contact layer 9 heavily doped with Si are stacked on a substrate 1.Type: ApplicationFiled: June 24, 2005Publication date: October 19, 2006Inventors: Yasuhiro Oda, Kenji Kurishima, Haruki Yokoyama, Takashi Kobayashi
-
Patent number: 5483919Abstract: An atomic layer epitaxy method uses an organometal consisting of a metal and an alkyl group and having a self-limiting mechanism. At least one bond between the metal and the alkyl group of the organometal is dissociated, and organometal molecules consisting of the metal and the alkyl group, and a hydride or organometal molecules consisting of a different metal are alternately supplied on a substrate while at least one bond is left, thereby growing an atomic layer on the substrate. An atomic layer epitaxy apparatus is also disclosed.Type: GrantFiled: August 17, 1994Date of Patent: January 16, 1996Assignee: Nippon Telegraph and Telephone CorporationInventors: Haruki Yokoyama, Masanori Shinohara