Patents by Inventor Norihiro Iwai
Norihiro Iwai 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: 20110064108Abstract: A method of manufacturing a surface emitting laser element of a vertical cavity type in accordance with the present invention is characterized in that comprises the following steps of: applying a process of accumulations on a substrate, the process sequentially including accumulating a reflecting mirror of a multilayered film layer at a lower side thereof on to the substrate, and accumulating layers of a semiconductor as a plurality thereof on to the reflecting mirror of the multilayered film layer at the lower side thereof, that comprises an active layer and that further comprises a contact layer at a top layer thereof as well; forming a first layer of a dielectric substance as a process of a formation of the first layer of the dielectric substance at a part of regions on the contact layer; forming an electrode of an annular shape as a process of a formation of the electrode of the annular shape on the contact layer, that has an open part at a center thereof, in order to be arranged for the first layer of thType: ApplicationFiled: September 16, 2009Publication date: March 17, 2011Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Keishi Takaki, Norihiro Iwai, Koji Hiraiwa
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Patent number: 7907653Abstract: In the surface emitting laser, low threshold electric current and high-power output are achieved while maintaining single mode characteristics. The surface emitting laser comprises a layered structure formed on a GaAs substrate 10 is comprised of: a semiconductor lower DBR mirror 12, a cladding layer 14, a n-type contact layer 16, an active layer 18, an electric current constricting layer 20, a p-type cladding layer 22, a p-type contact layer 24, a phase adjusting layer 36 and a dielectric upper DBR mirror 28. The surface emitting laser should be formed such that the diameter X (?m) of the opening diameter of the previously mentioned electric current constricting layer 20 and diameter Y (?m) of the phase adjusting layer satisfy the following relation: X+1.9??Y?X+5.0? (wherein ? indicates oscillation wavelength (?m) of the surface emitting laser).Type: GrantFiled: February 18, 2009Date of Patent: March 15, 2011Assignee: Furukawa Electric Co., Ltd.Inventors: Norihiro Iwai, Keishi Takaki, Suguru Imai
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Patent number: 7888145Abstract: A selective oxidation layer is formed by alternately growing an AlAs layer and an XAs layer containing a group III element X with a thickness ratio in a range between 97:3 and 99:1 on a plurality of semiconductor layers including an active layer. The selective oxidation layer is selectively oxidized to manufacture a vertical-cavity surface-emitting laser.Type: GrantFiled: February 11, 2008Date of Patent: February 15, 2011Assignee: The Furukawa Electric Co., Ltd.Inventors: Keishi Takaki, Norihiro Iwai, Hitoshi Shimizu, Takeo Kageyama
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Patent number: 7885307Abstract: A vertical-cavity surface-emitting (VCSEL) device has a layer structure including a top DBR mirror, an active layer, a current confinement oxide layer, and a bottom DBR mirror, the layer structure being configured as a mesa post. The current confinement oxide layer has a central current injection area and a peripheral current blocking area oxidized from the sidewall of the mesa post. The mesa post has a substantially square cross-sectional shape, thereby allowing an oxidation heat treatment to configure a substantially circular current injection area in the current-confinement oxide layer.Type: GrantFiled: October 19, 2006Date of Patent: February 8, 2011Assignee: The Furukawa Electric Co., Ltd.Inventors: Kinuka Tanabe, Yoshihiko Ikenaga, Norihiro Iwai, Takeo Kageyama, Koji Hiraiwa, Hirokazu Yoshikawa
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Patent number: 7881353Abstract: Provided is a surface emitting laser element array of low cost and high reliability. The surface emitting laser element array has a substrate having a semiconductor of a first conduction type; and a plurality of surface emitting laser elements each having, above the substrate, an active layer sandwiched between a first conduction type semiconductor layer area and a second conduction type semiconductor layer area and disposed between a upper reflective mirror and a lower reflective mirror, the surface emitting laser elements being separated from each other by an electric separation structure formed having such a depth as to reach the substrate. The first conduction type semiconductor layer area is arranged between the substrate and the active layer.Type: GrantFiled: March 30, 2009Date of Patent: February 1, 2011Assignee: Furukawa Electric Co., Ltd.Inventors: Takeo Kageyama, Keishi Takaki, Naoki Tsukiji, Norihiro Iwai, Hitoshzi Shimizu, Yasumasa Kawakita, Suguru Imai
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Patent number: 7881359Abstract: A surface-emitting semiconductor laser device includes a semi-insulating substrate, a layer structure with a bottom multilayer reflector, an n-type cladding layer, an active layer structure for emitting laser, a p-type cladding layer and a top multilayer reflector with a dielectric material, consecutively formed on the semi-insulating substrate, the active layer structure, the p-type cladding layer and the top multilayer reflector, configuring a mesa post formed on a portion of the n-type cladding layer, the p-type cladding layer or the p-type multilayer reflector. The surface-emitting semiconductor laser includes a p-side electrode formed on another portion of the p-type cladding layer, and an n-side electrode formed on another portion of the n-type cladding layer. The n-side electrode includes a substantially uniform Au film and AuGeNi film or AuGe film consecutively formed on the n-type cladding layer, and an alloy is formed between said Au film and said AuGeNi film or AuGe film.Type: GrantFiled: April 15, 2008Date of Patent: February 1, 2011Assignee: The Furukawa Electric Co., LtdInventors: Noriyuki Yokouchi, Norihiro Iwai
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Publication number: 20110003403Abstract: A method of performing a wafer level burn-in test for a plurality of surface-emitting laser devices formed on a wafer includes causing a plurality of contact electrodes arranged in a same plane with a pitch same as that of the surface-emitting laser devices being electrically connected to each other to have contact with pad electrodes of the surface-emitting laser devices, respectively, and applying a current to second electrodes of the surface-emitting laser devices and the contact electrodes. The wafer level burn-in test is performed while heating the wafer at a predetermined temperature. Laser lights emitted from the surface-emitting laser devices are monitored during the wafer level burn-in test.Type: ApplicationFiled: June 8, 2010Publication date: January 6, 2011Applicant: THE FURUKAWA ELECTRIC CO., LTDInventors: Koji HIRAIWA, Takeo Kageyama, Norihiro Iwai, Keishi Takaki
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Patent number: 7801198Abstract: A surface emitting laser element includes an active layer and a dielectric multilayer mirror formed with a plurality of dielectric layers having different refractive indices for reflecting a light generated in the active layer. At least one of boundaries between the dielectric layers is formed to have a predetermined surface roughness to obtain a desired target reflectance of the dielectric multilayer mirror.Type: GrantFiled: March 28, 2008Date of Patent: September 21, 2010Assignee: The Furukawa Electric Co., Ltd.Inventors: Takeo Kageyama, Norihiro Iwai, Yasumasa Kawakita, Keishi Takaki, Peter Nyakas
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Publication number: 20100232465Abstract: A semiconductor light emitting element, comprises: an active layer; a first electrode and second electrode that inject current to the active layer; a semiconductor layer between the active layer and the first electrode; and a dielectric layer that is provided on the semiconductor layer and through which light from the active layer passes; wherein the first electrode is provided on the semiconductor layer, has an opening through which light from the active layer passes, and comprises a first electrode layer that comes in contact with and is provided on the semiconductor layer, and a second electrode layer that is provided on the first electrode layer, with the first electrode layer having less reactivity with the semiconductor layer than the second electrode layer; and the dielectric layer is provided inside the opening such that the end section on the opening side of the first electrode layer extends from the top of the semiconductor layer to the top of the dielectric layer.Type: ApplicationFiled: January 7, 2010Publication date: September 16, 2010Applicant: FURUKAWA ELECTRIC CO., LTDInventors: Naoki TSUKIJI, Norihiro IWAI, Keishi TAKAKI, Koji HIRAIWA
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Patent number: 7778297Abstract: A convex-portion forming layer is formed between a current-confinement aperture and a multilayer mirror, and forms a convex portion on each boundary between layers forming the multilayer mirror. The convex portion includes a plane equal to or larger than a spot size of the laser light, where the spot size is decided by a diameter of the current-confinement aperture, a predetermined diffraction angle of the laser light due to the current-confinement aperture, and a distance from the current-confinement aperture.Type: GrantFiled: March 27, 2008Date of Patent: August 17, 2010Assignee: The Furukawa Electric Co., Ltd.Inventors: Takeo Kageyama, Norihiro Iwai, Yasumasa Kawakita
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Publication number: 20100195689Abstract: A surface emitting laser element array comprises a plurality of surface emitting laser elements (15) on a same substrate (1) each comprising a mesa post formed of a laminated structure including an active layer (4) for reducing a crosstalk between the surface emitting laser elements constituting the surface emitting laser element array, and for improving a high speed response, wherein each of the surface emitting laser elements (15) comprises a first electrode (9), a second electrode (10) and a third electrode (11) that have a polarity different from that of the first electrode (9); the first electrode (9) is arranged on the mesa post; the second electrode (10) is arranged on one surface of the substrate (1) same as that of the first electrode (9); the third electrode (11) is arranged on the other surface of the substrate (1) opposite to that of the first electrode and the second electrode (9, 10) and is provided as a common electrode of the surface emitting laser elements (15); and an electric current is appType: ApplicationFiled: September 1, 2006Publication date: August 5, 2010Applicant: The Furukawa Electric Co., Ltd.Inventors: Maiko Ariga, Takeo Kageyama, Norihiro Iwai, Kazuaki Nishikata
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Publication number: 20100086311Abstract: A surface emitting laser includes a lower semiconductor multilayer mirror formed of a plurality of pairs of a high-refractive-index area and a low-refractive-index area; an active layer vertically sandwiched by cladding layers; a current confinement layer of AlzGa1-zAs having an oxide area in a peripheral portion of the current confinement layer, where 0.95?z?1; and an upper semiconductor multilayer mirror formed of a plurality of pairs of a high-refractive-index area and a low-refractive-index area. The low-refractive-index area of at least one of the lower semiconductor multilayer mirror and the upper semiconductor multilayer mirror includes an Alz1Ga1-z1As layer with a thickness thinner than that of the current confinement layer, where z?z1.Type: ApplicationFiled: December 10, 2009Publication date: April 8, 2010Applicant: The FURUKAWA ELECTRIC CO., LTD.Inventors: Hitoshi SHIMIZU, Setiagung Casimirus, Yasukazu Shiina, Takeshi Hama, Norihiro Iwai
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Patent number: 7656924Abstract: A surface emitting laser includes a lower semiconductor multilayer mirror formed of a plurality of pairs of a high-refractive-index area and a low-refractive-index area; an active layer vertically sandwiched by cladding layers; a current confinement layer of AlzGa1-zAs having an oxide area in a peripheral portion of the current confinement layer, where 0.95?z?1; and an upper semiconductor multilayer mirror formed of a plurality of pairs of a high-refractive-index area and a low-refractive-index area. The low-refractive-index area of at least one of the lower semiconductor multilayer mirror and the upper semiconductor multilayer mirror includes an Alz1Ga1-z1As layer with a thickness thinner than that of the current confinement layer, where z?z1.Type: GrantFiled: October 5, 2004Date of Patent: February 2, 2010Assignee: The Furukawa Electric Co., Ltd.Inventors: Hitoshi Shimizu, Setiagung Casimirus, Yasukazu Shiina, Takeshi Hama, Norihiro Iwai
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Publication number: 20090310637Abstract: A convex-portion forming layer is formed between a current-confinement aperture and a multilayer mirror, and forms a convex portion on each boundary between layers forming the multilayer mirror. The convex portion includes a plane equal to or larger than a spot size of the laser light, where the spot size is decided by a diameter of the current-confinement aperture, a predetermined diffraction angle of the laser light due to the current-confinement aperture, and a distance from the current-confinement aperture.Type: ApplicationFiled: March 27, 2008Publication date: December 17, 2009Applicant: The Furukawa Electric Co, Ltd.Inventors: Takeo Kageyama, Norihiro Iwai, Yasumasa Kawakita
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Publication number: 20090304036Abstract: In the surface emitting laser, low threshold electric current and high-power output are achieved while maintaining single mode characteristics. The surface emitting laser comprises a layered structure formed on a GaAs substrate 10 is comprised of: a semiconductor lower DBR mirror 12, a cladding layer 14, a n-type contact layer 16, an active layer 18, an electric current constricting layer 20, a p-type cladding layer 22, a p-type contact layer 24, a phase adjusting layer 36 and a dielectric upper DBR mirror 28. The surface emitting laser should be formed such that the diameter X (?m) of the opening diameter of the previously mentioned electric current constricting layer 20 and diameter Y (?m) of the phase adjusting layer satisfy the following relation: X+1.9??Y?X+5.0? (wherein ? indicates oscillation wavelength (?m) of the surface emitting laser).Type: ApplicationFiled: February 18, 2009Publication date: December 10, 2009Applicant: The Furukawa Electric Co., LTDInventors: Norihiro Iwai, Keishi Takaki, Suguru Imai
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Publication number: 20090268773Abstract: A surface emitting laser element that includes a cylindrical mesa post in which a plurality of semiconductor layers including an active layer is grown and that emits a laser light in a direction perpendicular to a substrate surface, the surface emitting laser element including a dielectric multilayer film on a top surface of the mesa post in at least a portion over a current injection area of the active layer; and a dielectric portion that includes layers fewer than layers of the dielectric multilayer film and that is arranged on a portion excluding the portion over the current injection area on the top surface of the mesa post and on at least part of a side surface of the mesa post.Type: ApplicationFiled: April 24, 2008Publication date: October 29, 2009Applicant: THE FURUKAWA ELECTRIC CO.,LTD.,Inventors: Norihiro IWAI, Takeo Kageyama, Kinuka Tanabe
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Publication number: 20090245312Abstract: Provided is a surface emitting laser element array of low cost and high reliability. The surface emitting laser element array has a substrate having a semiconductor of a first conduction type; and a plurality of surface emitting laser elements each having, above the substrate, an active layer sandwiched between a first conduction type semiconductor layer area and a second conduction type semiconductor layer area and disposed between a upper reflective mirror and a lower reflective mirror, the surface emitting laser elements being separated from each other by an electric separation structure formed having such a depth as to reach the substrate. The first conduction type semiconductor layer area is arranged between the substrate and the active layer.Type: ApplicationFiled: March 30, 2009Publication date: October 1, 2009Applicant: THE FURUKAWA ELECTRIC CO., LTDInventors: Takeo Kageyama, Keishi Takaki, Naoki Tsukiji, Norihiro Iwai, Hitoshzi Shimizu, Yasumasa Kawakita, Suguru Imai
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Publication number: 20080273569Abstract: A VCSEL device includes a polyimide having a larger thickness (d1) on the surface of a semiconductor layer structure in a peripheral area 54, which is separated from a mesapost by an annular groove 52. The top surface of the central mesapost 30 is located at a lower position compared to the top surface of the peripheral area 54. A structure is obtained wherein the mesapost is not contacted by a jig or probe during handling the device in the test or assembly thereof.Type: ApplicationFiled: July 2, 2008Publication date: November 6, 2008Applicant: The Furukawa Electric Co, Ltd.Inventors: Koji HIRAIWA, Takeo Kageyama, Norihiro Iwai, Keishi Takaki
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Publication number: 20080254566Abstract: A surface-emitting semiconductor laser device includes a semi-insulating substrate, a layer structure with a bottom multilayer reflector, an n-type cladding layer, an active layer structure for emitting laser, a p-type cladding layer and a top multilayer reflector with a dielectric material, consecutively formed on the semi-insulating substrate, the active layer structure, the p-type cladding layer and the top multilayer reflector, configuring a mesa post formed on a portion of the n-type cladding layer, the p-type cladding layer or the p-type multilayer reflector. The surface-emitting semiconductor laser includes a p-side electrode formed on another portion of the p-type cladding layer, and an n-side electrode formed on another portion of the n-type cladding layer. The n-side electrode includes a substantially uniform Au film and AuGeNi film or AuGe film consecutively formed on the n-type cladding layer, and an alloy is formed between said Au film and said AuGeNi film or AuGe film.Type: ApplicationFiled: April 15, 2008Publication date: October 16, 2008Applicant: THE FURUKAWA ELECTRIC CO., LTD.Inventors: Noriyuki YOKOUCHI, Norihiro Iwai
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Publication number: 20080240192Abstract: A surface emitting laser element includes an active layer and a dielectric multilayer mirror formed with a plurality of dielectric layers having different refractive indices for reflecting a light generated in the active layer. At least one of boundaries between the dielectric layers is formed to have a predetermined surface roughness to obtain a desired target reflectance of the dielectric multilayer mirror.Type: ApplicationFiled: March 28, 2008Publication date: October 2, 2008Applicant: The Furukawa Electric Co, Ltd.Inventors: Takeo KAGEYAMA, Norihiro Iwai, Yasumasa Kawakita, Keishi Takaki, Peter Nyakas