Patents by Inventor Kazushi Nakano

Kazushi Nakano 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: 5766345
    Abstract: An epitaxial growth method of semiconductor can reliably avoid irregularities from being produced when a II-VI compound semiconductor is grown epitaxially. When this method is applied to a method of manufacturing a semiconductor light-emitting device, it is possible to obtain a semiconductor light-emitting device having a long life and excellent light-emitting characteristic. When a II-VI compound semiconductor is grown epitaxially, a VI/II ratio, i.e., a supplying ratio of VI-group element and II-group element used in the epitaxial growth is selected in a range of from 1.3 to 2.5.
    Type: Grant
    Filed: October 16, 1995
    Date of Patent: June 16, 1998
    Assignee: Sony Corporation
    Inventors: Shigetaka Tomiya, Kazushi Nakano, Satoshi Ito, Rikako Minatoya
  • Patent number: 5740193
    Abstract: A II-VI group compound semiconductor light-emitting device can emit light of a short wavelength at room temperature. Operation characteristics, such as current--voltage characteristics and current--light output characteristics can be stabilized and a life of this semiconductor light-emitting device can be extended. The semiconductor light-emitting device comprises a substrate (1), at least a first cladding layer (2) of a first conductivity type, an active layer (3) and a second cladding layer (4) of a second conductivity type, wherein at least the active layer (3) is made of a II-VI group compound semiconductor and the active layer (3) is doped by either or both of n-type and p-type dopants.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: April 14, 1998
    Assignee: Sony Corporation
    Inventors: Hiroyuki Okuyama, Akira Ishibashi, Eisaku Kato, Hiroshi Yoshida, Kazushi Nakano, Masakazu Ukita, Satoru Kijima, Sakurako Okamoto
  • Patent number: 5665977
    Abstract: A semiconductor light emitting device comprises a first cladding layer, an active layer and a second cladding layer which are stacked on a semiconductor substrate. At least a part of the first cladding layer and the second cladding layer has a superlattice structure comprising II-VI compound semiconductor. Another semiconductor light emitting device comprises a first cladding layer, a first guide layer, an active layer, a second guide layer and a second cladding layer which are stacked on semiconductor substrate. At least a part of the first cladding layer, the first guide layer, the second cladding layer and the second guide layer has a superlattice structure. Still another semiconductor light emitting device comprises a defect decomposing layer, a defect blocking layer, first cladding layer, an active layer, a second cladding layer which are stacked on a semiconductor substrate. The defect decomposing layer and the defect blocking layer comprise a superlattice structure.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: September 9, 1997
    Assignee: Sony Corporation
    Inventors: Akira Ishibashi, Satoshi Matsumoto, Masaharu Nagai, Satoshi Ito, Shigetaka Tomiya, Kazushi Nakano, Etsuo Morita
  • Patent number: 5657336
    Abstract: A II-VI group compound semiconductor light-emitting device can emit light of a short wavelength at room temperature. Operation characteristics, such as current--voltage characteristics and current--light output characteristics can be stabilized and a life of this semiconductor light-emitting device can be extended. The semiconductor light-emitting device comprises a substrate (1), at least a first cladding layer (2) of a first conductivity type, an active layer (3) and a second cladding layer (4) of a second conductivity type, wherein at least the active layer (3) is made of a II-VI group compound semiconductor and the active layer (3) is doped by either or both of n-type and p-type dopants.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: August 12, 1997
    Assignee: Sony Corporation
    Inventors: Hiroyuki Okuyama, Akira Ishibashi, Eisaku Kato, Hiroshi Yoshida, Kazushi Nakano, Masakazu Ukita, Satoru Kijima, Sakurako Okamoto
  • Patent number: 5633514
    Abstract: The semiconductor light emitting device includes a semiconductor substrate (1), a first conductivity type first cladding layer (2) deposited on the semiconductor substrate (1), an active layer (4) deposited on the first cladding layer (2), and the second conductivity type second cladding layer (6) deposited on the active layer (4). The first and the second cladding layers (2, 6) are made of the II/VI-compound semiconductors including at least one kind of group II elements such as Zn, Hg, Cd, Mg and at least one kind of group VI elements such as S, Se, Te. The lattice mismatching .DELTA.a/a (%) between at least one of the first cladding layer (2) and the second cladding layer (6) and the substrate is set within the range of -0.9%.ltoreq..DELTA.Aa/a.ltoreq.0.5% (reference symbols a and a.sub.c represent the lattice constant of the semiconductor substrate and the lattice constant of at least either of the first and second cladding layers, and .DELTA.a is obtained from .DELTA.a=a.sub.c -a).
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: May 27, 1997
    Assignee: Sony Corporation
    Inventors: Masashi Shiraishi, Satoshi Ito, Kazushi Nakano, Akira Ishibashi, Masao Ikeda, Hiroyuki Okuyama, Katsuhiro Akimoto, Tomonori Hino, Masakazu Ukita
  • Patent number: 5567960
    Abstract: A lifetime of a II/VI-compound semiconductor light emitting device can be extended. The II/VI-compound semiconductor light emitting device includes an active layer (4) and a p-side cladding layer (6). An active-layer side portion (26) of the p-side cladding layer (6) is formed as a lightly impurity-doped region or a non-doped region.
    Type: Grant
    Filed: April 27, 1995
    Date of Patent: October 22, 1996
    Assignee: Sony Corporation
    Inventors: Akira Ishibashi, Satoshi Ito, Hiroyuki Okuyama, Kazushi Nakano, Kenji Kondo, Reiko Takeishi
  • Patent number: 5515393
    Abstract: A semiconductor laser using a II-VI compound semiconductor as the material for cladding layers, capable of emitting a blue to green light is disclosed. In an aspect of the semiconductor laser, an n-type ZnSe buffer layer, an n-type ZnMgSSe cladding layer, an active layer made of, for example, ZnCdSe, a p-type ZnMgSSe cladding layer and a p-type ZnSe contact layer are stacked in sequence on an n-type GaAs substrate. A p-side electrode such as an Au/Pd electrode is provided in contact with the p-type ZnSe contact layer. An n-side electrode such as an In electrode is provided on the back surface of the n-type GaAs substrate. In another aspect of the semiconductor laser, an n-type optical guiding layer made of ZnSSe, ZnMgSSe or ZnSe is provided between the n-type ZnMgSSe cladding layer and the active layer, and a p-type optical guiding layer made of ZnSSe, ZnMgSSe or ZnSe is provided between the p-type ZnMgSSe cladding layer and the active layer.
    Type: Grant
    Filed: August 4, 1993
    Date of Patent: May 7, 1996
    Assignee: Sony Corporation
    Inventors: Hiroyuki Okuyama, Katsuhiro Akimoto, Takao Miyajima, Masafumi Ozawa, Yuko Morinaga, Futoshi Hiei, Kazushi Nakano, Toyoharu Ohata