Patents by Inventor Mikio Tazima
Mikio Tazima 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: 7897497Abstract: A light-generating semiconductor region is grown by epitaxy on a silicon substrate. The light-generating semiconductor region is a lamination of layers of semiconducting nitrides containing a Group III element or elements. The silicon substrate has a p-type impurity-diffused layer formed therein by thermal diffusion of the Group III element or elements from the light-generating semiconductor region as a secondary product of the epitaxial growth of this region on the substrate. The p-type impurity-diffused layer is utilized as a part of overvoltage protector diodes which are serially interconnected with each other and in parallel with the LED section of the device between a pair of electrodes.Type: GrantFiled: July 28, 2008Date of Patent: March 1, 2011Assignee: Sanken Electric Co., Ltd.Inventors: Yasuhiro Kamii, Arei Niwa, Junji Sato, Mikio Tazima
-
Patent number: 7893450Abstract: An aspect of the present invention inheres in a semiconductor light-emitting element includes a light-emitting functional stacked body including a light-emitting region having a light-emitting function, and including a light extraction surface for extracting light emitted from the light-emitting region, and an upward convex lens disposed on the light extraction surface.Type: GrantFiled: July 9, 2008Date of Patent: February 22, 2011Assignee: Sanken Electric Co., Ltd.Inventors: Mikio Tazima, Yoshiki Tada, Tetsuji Matsuo
-
Patent number: 7723732Abstract: A semiconductor light-emitting device includes a substrate having two main surfaces; and an active layer forming part, which is made of a compound semiconductor material, formed on one of the main surfaces, and includes an active layer. A plurality of holes, which pass through the active layer, are formed from the upper surface of the active layer forming part; a plurality of hollow parts, each of which corresponds to each hole, are provided between the active layer and the substrate; and the area of each hollow part is larger than that of the corresponding hole in plan view, and spreads on the lower surface of the active layer forming part, so as to expose a part of the lower surface of the active layer forming part, which overlaps the hollow part in plan view.Type: GrantFiled: November 7, 2007Date of Patent: May 25, 2010Assignee: Sanken Electric Co., Ltd.Inventors: Mikio Tazima, Yoshiki Tada
-
Patent number: 7687323Abstract: The method is disclosed as applied to roughening the light-emitting surface of an LED wafer for reduction of the internal total reflection of the light generated. A masking film of silver is first deposited on the surface of a wafer to be diced into LED chips. Then the masking film is heated to cause its coagulation into discrete particles. Then, using the silver particles as a mask, the wafer surface is dry etched to create pits therein. The deposition of silver on the wafer surface and its thermal coagulation into particles may be either successive or concurrent.Type: GrantFiled: April 16, 2008Date of Patent: March 30, 2010Assignee: Sanken Electric Co., Ltd.Inventors: Tetsuji Matsuo, Mikio Tazima, Takashi Kato
-
Publication number: 20090026476Abstract: An aspect of the present invention inheres in a semiconductor light-emitting element includes a light-emitting functional stacked body including a light-emitting region having a light-emitting function, and including a light extraction surface for extracting light emitted from the light-emitting region, and an upward convex lens disposed on the light extraction surface.Type: ApplicationFiled: July 9, 2008Publication date: January 29, 2009Applicant: Sanken Electric Co., Ltd.Inventors: Mikio Tazima, Yoshiki Tada, Tetsuji Matsuo
-
Publication number: 20080308823Abstract: A light-generating semiconductor region is grown by epitaxy on a silicon substrate. The light-generating semiconductor region is a lamination of layers of semiconducting nitrides containing a Group III element or elements. The silicon substrate has a p-type impurity-diffused layer formed therein by thermal diffusion of the Group III element or elements from the light-generating semiconductor region as a secondary product of the epitaxial growth of this region on the substrate. The p-type impurity-diffused layer is utilized as a part of overvoltage protector diodes which are serially interconnected with each other and in parallel with the LED section of the device between a pair of electrodes.Type: ApplicationFiled: July 28, 2008Publication date: December 18, 2008Applicant: Sanken Electric Co., Ltd.Inventors: Yasuhiro Kamii, Arei Niwa, Junji Sato, Mikio Tazima
-
Patent number: 7449727Abstract: An LED incorporating an overvoltage protector with a minimum of space requirement. The LED itself comprises a p-type semiconductor substrate, a light-generating semiconductor region grown epitaxially thereon, a first electrode on the light-generating semiconductor region, and a second electrode on the underside of the substrate. The standard method of LED fabrication is such that the substrate is notionally divisible into a main portion in register with the overlying light-generating semiconductor region and, surrounding the main portion, a tubular marginal portion needed for dicing the wafer into individual squares or dice. The overvoltage protector comprises an n-type semiconductor film formed on the marginal portion of the substrate and held against the side surfaces of the light-generating semiconductor region via an insulating film.Type: GrantFiled: January 31, 2006Date of Patent: November 11, 2008Assignee: Sanken Electric Co., Ltd.Inventors: Junji Sato, Mikio Tazima, Tetsuji Moku, Arei Niwa, Yasuhiro Kamii
-
Patent number: 7446342Abstract: There is provided a semiconductor light emitting diode and a method of manufacturing the same that enable voltage in the forward direction to be decreased while allowing light extraction efficiency to be improved. This semiconductor light emitting diode is formed by a substrate, a light emitting portion that is disposed on one main surface of the substrate, a first electrode that is disposed on the light emitting portion, a pad electrode that is disposed on the first electrode, concave portions that are formed on at least a portion of the one main surface of the substrate, and a conductive layer that is formed from a conductive material that is disposed in the concave portions and reflects light emitted from the light emitting portion.Type: GrantFiled: February 8, 2006Date of Patent: November 4, 2008Assignee: Sanken Electric Co., Ltd.Inventors: Mikio Tazima, Tetsuji Moku, Junji Sato, Yasuhiro Kamii, Arei Niwa
-
Publication number: 20080261340Abstract: The method is disclosed as applied to roughening the light-emitting surface of an LED wafer for reduction of the internal total reflection of the light generated. A masking film of silver is first deposited on the surface of a wafer to be diced into LED chips. Then the masking film is heated to cause its coagulation into discrete particles. Then, using the silver particles as a mask, the wafer surface is dry etched to create pits therein. The deposition of silver on the wafer surface and its thermal coagulation into particles may be either successive or concurrent.Type: ApplicationFiled: April 16, 2008Publication date: October 23, 2008Applicant: SANKEN ELECTRIC CO., LTD.Inventors: Tetsuji Matsuo, Mikio Tazima, Takashi Kato
-
Publication number: 20080128716Abstract: A semiconductor light-emitting device includes a substrate having two main surfaces; and an active layer forming part, which is made of a compound semiconductor material, formed on one of the main surfaces, and includes an active layer. A plurality of holes, which pass through the active layer, are formed from the upper surface of the active layer forming part; a plurality of hollow parts, each of which corresponds to each hole, are provided between the active layer and the substrate; and the area of each hollow part is larger than that of the corresponding hole in plan view, and spreads on the lower surface of the active layer forming part, so as to expose a part of the lower surface of the active layer forming part, which overlaps the hollow part in plan view.Type: ApplicationFiled: November 7, 2007Publication date: June 5, 2008Applicant: SANKEN ELECTRIC CO., LTD.Inventors: Mikio Tazima, Yoshiki Tada
-
Publication number: 20080048202Abstract: A semiconductor device may include, but is not limited to, a substrate, a compound semiconductor epitaxial layer, and a first reflecting layer. The substrate may have a main face. The substrate may have at least one cavity that is adjacent to the main face. The compound semiconductor epitaxial layer may have first and second faces adjacent to each other. The first face may contact with the main face. The second face may face toward the at least one cavity. The compound semiconductor epitaxial layer may include, but is not limited to, at least one light emitting layer that emits light. The first reflecting layer may be in the at least one cavity. The first reflecting layer may contact with the second face. The first reflecting layer may be higher in light-reflectivity than the substrate.Type: ApplicationFiled: July 24, 2007Publication date: February 28, 2008Applicant: SANKEN ELECTRIC CO., LTD.Inventors: Mikio Tazima, Yoshiki Tada, Yasuhiro Kamii
-
Publication number: 20070114515Abstract: An LED is disclosed which comprises a nitride-made main semiconductor region formed on a substrate for generating light, and an electrode formed on the main semiconductor region to a thickness sufficiently small to transmit the light from the main semiconductor region. The electrode is made from a silver-base alloy, rather than from silver only, that contains an additive or additives selected to protect the electrode against oxidation and/or sulfurization and to enhance the chemical stability of the electrode without loss in contact ohmicity.Type: ApplicationFiled: January 15, 2007Publication date: May 24, 2007Applicant: Sanken Electric Co., Ltd.Inventors: Hidekazu Aoyagi, Tetsuji Matsuo, Tetsuji Moku, Mikio Tazima
-
Patent number: 7199401Abstract: An LED includes a semiconductor region having an active layer sandwiched between two confining layers of opposite conductivity types for generating heat. A cathode is arranged centrally on one of the opposite major surfaces of the semiconductor region from which is emitted the light. Attached to the other major surface of the semiconductor region, via an ohmic contact layer, is a reflective metal layer for reflecting the light that has traversed the ohmic contact layer, back toward the semiconductor region. A transparent antidiffusion layer is interposed between the ohmic contact layer and the reflective layer in order to prevent the ohmic contact layer and the reflective layer from thermally diffusing from one into the other to the impairment of the reflectivity of the reflective layer.Type: GrantFiled: February 16, 2005Date of Patent: April 3, 2007Assignee: Sanken Electric Co., Ltd.Inventors: Mikio Tazima, Masahiro Sato, Hidekazu Aoyagi, Tetsuji Matsuo
-
Publication number: 20060193355Abstract: There is provided a semiconductor light emitting diode and a method of manufacturing the same that enable voltage in the forward direction to be decreased while allowing light extraction efficiency to be improved. This semiconductor light emitting diode is formed by a substrate, a light emitting portion that is disposed on one main surface of the substrate, a first electrode that is disposed on the light emitting portion, a pad electrode that is disposed on the first electrode, concave portions that are formed on at least a portion of the one main surface of the substrate, and a conductive layer that is formed from a conductive material that is disposed in the concave portions and reflects light emitted from the light emitting portion.Type: ApplicationFiled: February 8, 2006Publication date: August 31, 2006Applicant: Sanken Electric Co., LTD.Inventors: Mikio Tazima, Tetsuji Moku, Junji Sato, Yasuhiro Kamii, Arei Niwa
-
Publication number: 20060181828Abstract: An LED incorporating an overvoltage protector with a minimum of space requirement. The LED itself comprises a p-type semiconductor substrate, a light-generating semiconductor region grown epitaxially thereon, a first electrode on the light-generating semiconductor region, and a second electrode on the underside of the substrate. The standard method of LED fabrication is such that the substrate is notionally divisible into a main portion in register with the overlying light-generating semiconductor region and, surrounding the main portion, a tubular marginal portion needed for dicing the wafer into individual squares or dice. The overvoltage protector comprises an n-type semiconductor film formed on the marginal portion of the substrate and held against the side surfaces of the light-generating semiconductor region via an insulating film.Type: ApplicationFiled: January 31, 2006Publication date: August 17, 2006Applicant: Sanken Electric Co., Ltd.Inventors: Junji Sato, Mikio Tazima, Tetsuji Moku, Arei Niwa, Yasuhiro Kamii
-
Publication number: 20050184300Abstract: An LED includes a semiconductor region having an active layer sandwiched between two confining layers of opposite conductivity types for generating heat. A cathode is arranged centrally on one of the opposite major surfaces of the semiconductor region from which is emitted the light. Attached to the other major surface of the semiconductor region, via an ohmic contact layer, is a reflective metal layer for reflecting the light that has traversed the ohmic contact layer, back toward the semiconductor region. A transparent antidiffusion layer is interposed between the ohmic contact layer and the reflective layer in order to prevent the ohmic contact layer and the reflective layer from thermally diffusing from one into the other to the impairment of the reflectivity of the reflective layer.Type: ApplicationFiled: February 16, 2005Publication date: August 25, 2005Inventors: Mikio Tazima, Masahiro Sato, Hidekazu Aoyagi, Tetsuji Matsuo