Patents by Inventor Toshinari Fujimori
Toshinari Fujimori 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: 7164157Abstract: A light emitting device including a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity-modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.Type: GrantFiled: October 20, 2005Date of Patent: January 16, 2007Assignee: Mitsubishi Chemical CorporationInventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
-
Patent number: 7102174Abstract: The present invention discloses a light emitting device comprising a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.Type: GrantFiled: May 21, 2001Date of Patent: September 5, 2006Assignee: Mitsubishi Chemical CorporationInventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
-
Publication number: 20060038185Abstract: A light emitting device including a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 ?m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity-modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.Type: ApplicationFiled: October 20, 2005Publication date: February 23, 2006Applicant: MITSUBISHI CHEMICAL CORPORATIONInventors: Hideyoshi Horie, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
-
Patent number: 6744074Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.Type: GrantFiled: October 3, 2001Date of Patent: June 1, 2004Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
-
Patent number: 6677618Abstract: Disclosed compound semiconductor light emitting devices have a substrate, a compound semiconductor layer, formed on the substrate, containing a first conductive type clad layer, an active layer, and a second conductive type clad layer, and a resonator structure formed of two opposing facets of the compound semiconductor layer, wherein surfaces of the first conductive type clad layer, the active layer, and the second conductive type clad layer forming the facet of the compound semiconductor are covered with a passivation layer, wherein at least one element constituting the facet of the compound semiconductor layer is not coupled to oxygen, and wherein a portion of the passivation layer adjacent to the facet of the compound semiconductor layer contains oxygen as a structural element.Type: GrantFiled: December 3, 1999Date of Patent: January 13, 2004Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
-
Publication number: 20020020847Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.Type: ApplicationFiled: October 3, 2001Publication date: February 21, 2002Applicant: MITSUBISHU CHEMICAL CORPORATIONInventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
-
Publication number: 20020014674Abstract: The present invention discloses a light emitting device comprising a substrate transparent at the emission wavelength and an active layer structure formed on such substrate, in which the thickness of the substrate is 75 &mgr;m or less, and/or a layer for suppressing spectral-intensity-modulation due to the substrate-mode is provided between the substrate and the active layer structure. Such device can suppress the spectral-intensity modulation due to the substrate-mode, which is observed for the case the substrate is transparent at the emission wavelength, to thereby provide a light emission device excellent in linearity of the current-light output characteristics, and to thereby improve the coupling characteristics with an external cavity.Type: ApplicationFiled: May 21, 2001Publication date: February 7, 2002Inventors: Horie Hideyoshi, Satoru Nagao, Yoshitaka Yamamoto, Toshinari Fujimori
-
Patent number: 6323052Abstract: Compound semiconductor light emitting devices capable of suppressing the surface state density on the facets of semiconductor light emitting devices such as semiconductor lasers for a long time and stable operating even when the passivation layer diffuses can be easily obtained. Compound semiconductor light emitting devices with an emission wavelength of &lgr; (nm) wherein a first conduction type of clad layer, an active layer and a second conduction type of clad layer are grown on a substrate and two facets are opposite to each other so as to form a cavity, characterized in that said active layer is transparent to the emission wavelength in the vicinities of the facets and that the surfaces of the first conduction type of clad layer, active layer and second conduction type of clad layer forming said facets are each coated with a passivation layer.Type: GrantFiled: June 11, 1998Date of Patent: November 27, 2001Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Hirotaka Ohta, Toshinari Fujimori
-
Patent number: 6172998Abstract: The present invention relates to a semiconductor laser diode comprising a GaAs substrate and at least a first conduction-type clad layer, an active layer containing In, Ga and As as component elements, a second conduction-type first clad layer, a current block layer and a second conduction-type second clad layer which are deposited on the substrate in order, wherein a current injection region is formed by said current block layer and said second conduction-type second clad layer, the effective refractive index step &Dgr;neff in the horizontal direction is from 2.5×10−3 to 5.0×10−3 at the emission wavelength, and the width W of the current injection region is from 1.5 to 2.5 &mgr;m. The semiconductor laser diode of the present invention is suited for uses where high output and long life-time are required, such as excitation light source for optical fiber amplifiers.Type: GrantFiled: November 17, 1997Date of Patent: January 9, 2001Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Hideki Goto
-
Patent number: 5920767Abstract: The disclosure describes a method of forming a groove in a structure of a semiconductor laser diode, which comprises a crystal growth procedure of epitaxial growth of a core layer comprising MP, wherein M represents one or more of elements belonging to group IIIb of periodic table and an upper layer comprising MAs, wherein M represents one or more of elements belonging to group IIIb of periodic table, successively on (100) surface of MAs crystals in a lower layer comprising MAs; a photolithography and wet etching procedure of, after forming an etching mask on the upper layer, forming an etching window to the etching mask; a first etching procedure of selective etching the upper layer; and a second etching procedure of selective etching other faces except for the face in which (111) face of MP crystals in the core layer is exposed.Type: GrantFiled: July 22, 1996Date of Patent: July 6, 1999Assignee: Mitsubishi Chemical CompanyInventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Nobuyuki Hosoi, Hideki Goto
-
Patent number: 5868834Abstract: The disclosure describes a method of manufacturing a Group II-VI compound semiconductor thin film by a vapor-phase epitaxy using an organic metal compound of Group II element and a hydride or an organic metal compound of Group VI element as the raw material, which comprises repeating alternate introduction of an organic metal compound of Group II element and a halide gas, a halogen gas or a mixture thereof; or adding a halide gas, a halogen gas or a mixture thereof to a gas for vapor-phase epitaxy.Type: GrantFiled: June 16, 1997Date of Patent: February 9, 1999Assignee: Mitsubishi Kasei CorporationInventors: Kenji Shimoyama, Toshinari Fujimori, Hideki Goto
-
Patent number: 5838028Abstract: The invention provides a semiconductor device having a structure wherein a layer comprising at least Al.sub.W Ga.sub.1-W As is formed on a substrate and a second etching stop layer, a first etching stop layer and a layer comprising Al.sub.Y Ga.sub.1-Y As are deposited on the layer comprising Al.sub.W Ga.sub.1-W As in the described order, with a portion of the layer comprising Al.sub.Y G.sub.1-Y As and a portion of the first etching stop layer being removed. This structure enables a desired ridge shape to be fabricated with good quality and allows for free selection of the Al mixed crystal ratio of the layer to be etched, and makes it possible to form the re-growth interface of GaAs. Thus, the qualty of crystal of the re-grown portion can be improved.Type: GrantFiled: May 22, 1997Date of Patent: November 17, 1998Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Hideki Gotoh
-
Patent number: 5608751Abstract: The disclosure describes a laser diode comprising a Group III-V compound single-crystal substrate of first conduction type; a first cladding layer of first conduction type composed of (Al.sub.m Ga.sub.1-m).sub.n In.sub.1-n P (0.3.ltoreq.m.ltoreq.1 and 0.3.ltoreq.n.ltoreq.0.75) and formed on said single-crystal substrate; an active layer composed of (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P (0.ltoreq.x.ltoreq.0.5 and 0.3.ltoreq.y.ltoreq.0.75) and formed on said first cladding layer; a second cladding layer of second conduction type composed of (Al.sub.m Ga.sub.1-m).sub.n In.sub.1-n P (0.3.ltoreq.m.ltoreq.1 and 0.3.ltoreq.n.ltoreq.0.75) and formed on said active layer and having a ridge; and a current blocking layer composed of Al.sub.u Ga.sub.1-u As.sub.v P.sub.1-v, (0.ltoreq.u.ltoreq.1 and 0.ltoreq.v.ltoreq.Type: GrantFiled: March 14, 1994Date of Patent: March 4, 1997Assignee: Mitsubishi Chemical CorporationInventors: Kenji Shimoyama, Toshinari Fujimori, Satoru Nagao, Hideki Gotoh
-
Patent number: 5566198Abstract: The disclosure describes a method of forming a groove in a structure of a semiconductor laser diode, which comprises a crystal growth procedure of epitaxial growth of a core layer comprising MP, wherein M represents one or more of elements belonging to group IIIb of periodic table and an upper layer comprising MAs, wherein M represents one or more of elements belonging to group IIIb of periodic table, successively on (100) surface of MAs crystals in a lower layer comprising MAs; a photolithography and wet etching procedure of, after forming an etching mask on the upper layer, forming an etching window to the etching mask; a first etching procedure of selective etching the upper layer; and a second etching procedure of selective etching other faces except for the face in which (111) face of MP crystals in the core layer is exposed.Type: GrantFiled: January 30, 1995Date of Patent: October 15, 1996Assignee: Mitsubishi Chemical CorporationInventors: Hideyoshi Horie, Toshinari Fujimori, Satoru Nagao, Nobuyuki Hosoi, Hideki Goto