Patents by Inventor Tetsuhiro Tanabe
Tetsuhiro Tanabe 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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Patent number: 7965753Abstract: An infrared element (10a) which includes at least a light emitting layer forming portion (9a) composed of, for example, a first conductivity type cladding layer (2a), an active layer (3a), and a second conductivity type cladding layer (4a) for emitting infrared light, is formed on a semiconductor substrate (1), and a red element (10b) which includes at least a light emitting layer forming portion (9b) composed of, for example, a first conductivity type cladding layer (2b), an active layer (3b), and a second conductivity type cladding layer (4b) for emitting red light, is formed on the same semiconductor substrate (1). And their second conductivity type cladding layers (4a and 4b) are made of the same material. As a result, forming process of their ridge portions may be communized and both of the elements can be formed respectively, with a window structure capable of high output operation.Type: GrantFiled: August 23, 2006Date of Patent: June 21, 2011Assignee: Rohm Co., Ltd.Inventor: Tetsuhiro Tanabe
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Publication number: 20100264411Abstract: There is provided a ZnO based compound semiconductor light emitting device which can emit light with high efficiency and from an entire surface while using ZnO based compound semiconductor which can be expected with higher light emitting efficiency than that of a GaN based compound. On an insulating substrate (1), an n-type layer (2), an active layer (3), and a p-type layer (4), made of ZnO based compound semiconductor materials, are laminated, wherein a specific resistance of the n-type layer is 0.001 ?·cm or more and 1 ?·cm or less, and a film thickness (?m) of the n-type layer is set in a value or more calculated by a formula (specific resistance (?·cm))×300, and an n-side electrode (5) is formed on an exposed portion of a surface of the n-type layer opposite to a surface being in contact with the substrate and a p-side electrode (6) is formed on the p-type layer.Type: ApplicationFiled: December 19, 2006Publication date: October 21, 2010Applicant: ROHM CO., LTD.Inventors: Tetsuo Fujii, Tetsuhiro Tanabe
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Publication number: 20100218723Abstract: A molecular beam cell includes a crucible (2) for containing a material (29), a coil heater (3) for heating the material (29), and a side reflector (5) for reflecting the heat from the coil heater (3). The molecular beam cell further includes a base (7) supporting the crucible (2), the coil heater (3) and the side reflector (5). The base (7) is held by a disc-shaped flange (9) via a plurality of posts (20). A purge gas introduction pipe (44) for supplying purge gas (48) into the crucible (2) is provided, whereby ambient gas (36) is prevented from coming into contact with the material (29).Type: ApplicationFiled: January 29, 2007Publication date: September 2, 2010Applicant: ROHM CO., LTDInventors: Takatoshi Yamamoto, Shinya Umemoto, Tetsuhiro Tanabe, Yoshio Nishimoto
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Patent number: 7711024Abstract: There is disclosed a monolithic semiconductor laser which is provided with an AlGaAs based semiconductor laser element (10a) and an InGaAlP based semiconductor laser element (10b) formed on a semiconductor substrate (1). The AlGaAs based semiconductor laser element (10a) is composed of an infrared light emitting layer forming portion (9a), which has an n-type cladding layer (2a), an active layer (3a) and a p-type cladding layer (4a) formed so as to have a ridge portion, and a current constriction layer (5a) provided on sides of the ridge portion, while the InGaP based semiconductor laser element (10b) is composed of a red light emitting layer forming portion (9a), which has an n-type cladding layer (2b), an active layer (3b) and a p-type cladding layer (4b) formed so as to have a ridge portion, and a current constriction layer (5b) provided on sides of the ridge portion.Type: GrantFiled: August 23, 2006Date of Patent: May 4, 2010Assignee: Rohm Co., Ltd.Inventor: Tetsuhiro Tanabe
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Patent number: 7605012Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.Type: GrantFiled: June 27, 2005Date of Patent: October 20, 2009Assignees: National Institute of Advanced Industrial Science & Tech., Rohm Co., Ltd.Inventors: Shigeru Niki, Paul Fons, Kakuya Iwata, Tetsuhiro Tanabe, Hidemi Takasu, Ken Nakahara
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Publication number: 20090086781Abstract: An infrared element (10a) which includes at least a light emitting layer forming portion (9a) composed of, for example, a first conductivity type cladding layer (2a), an active layer (3a), and a second conductivity type cladding layer (4a) for emitting infrared light, is formed on a semiconductor substrate (1), and a red element (10b) which includes at least a light emitting layer forming portion (9b) composed of, for example, a first conductivity type cladding layer (2b), an active layer (3b), and a second conductivity type cladding layer (4b) for emitting red light, is formed on the same semiconductor substrate (1). And their second conductivity type cladding layers (4a and 4b) are made of the same material. As a result, forming process of their ridge portions may be communized and both of the elements can be formed respectively, with a window structure capable of high output operation.Type: ApplicationFiled: August 23, 2006Publication date: April 2, 2009Applicant: ROHM CO., LTD.Inventor: Tetsuhiro Tanabe
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Publication number: 20090034569Abstract: There is disclosed a monolithic semiconductor laser which is provided with an AlGaAs based semiconductor laser element (10a) and an InGaAlP based semiconductor laser element (10b) formed on a semiconductor substrate (1). The AlGaAs based semiconductor laser element (10a) is composed of an infrared light emitting layer forming portion (9a), which has an n-type cladding layer (2a), an active layer (3a) and a p-type cladding layer (4a) formed so as to have a ridge portion, and a current constriction layer (5a) provided on sides of the ridge portion, while the InGaP based semiconductor laser element (10b) is composed of a red light emitting layer forming portion (9a), which has an n-type cladding layer (2b), an active layer (3b) and a p-type cladding layer (4b) formed so as to have a ridge portion, and a current constriction layer (5b) provided on sides of the ridge portion.Type: ApplicationFiled: August 23, 2006Publication date: February 5, 2009Applicant: ROHM CO., LTD.Inventor: Tetsuhiro Tanabe
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Patent number: 7132691Abstract: It has a structure in which an active layer (5) that emits light by electric current injection is sandwiched between an n-type cladding layer (4) and a p-type cladding layer (6) made of materials having a larger band gap than the active layer (5), wherein the active layer (5) is made, for example, of CdxZn1?xO (0?x<1). It is further more preferable if the cladding layers (4), (6) are made, for example, of MgyZn1?yO (0?y<1). This narrows the band gap of the ZnO materials, and an oxide semiconductor capable of being wet-etched, easy to handle with, and excellent in crystallinity can be used as a material for an active layer or a cladding layer of a semiconductor light emitting device such as a blue light emitting diode or a blue laser diode in which an active layer is sandwiched between cladding layers, so that a blue semiconductor light emitting device being excellent in light emission characteristics can be obtained.Type: GrantFiled: September 9, 1999Date of Patent: November 7, 2006Assignee: Rohm Co., Ltd.Inventors: Tetsuhiro Tanabe, Ken Nakahara
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Patent number: 6987029Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.Type: GrantFiled: November 17, 2003Date of Patent: January 17, 2006Assignees: National Institute of Advanced Industrial Science and Technology, Rohm Co., Ltd.Inventors: Shigeru Niki, Paul Fons, Kakuya Iwata, Tetsuhiro Tanabe, Hidemi Takasu, Ken Nakahara
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Publication number: 20050247954Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.Type: ApplicationFiled: June 27, 2005Publication date: November 10, 2005Inventors: Shigeru Niki, Paul Fons, Kakuya Iwata, Tetsuhiro Tanabe, Hidemi Takasu, Ken Nakahara
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Publication number: 20040099876Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.Type: ApplicationFiled: November 17, 2003Publication date: May 27, 2004Applicant: National Institute of Advanced Industrial Science and Technology and Rohm Co., Ltd.Inventors: Shigeru Niki, Paul Fons, Kakuya Iwata, Tetsuhiro Tanabe, Hidemi Takasu, Ken Nakahara
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Patent number: 6735230Abstract: On the surface of a conductive substrate (1) of GaAs, Ge, Si, etc., a semiconductor lamination section including a light emitting layer forming portion (11) that has at least an n-type layer (4) and a p-type layer (6) made from a compound semiconductor of a Group III element and nitrogen and that is laminated so as to form a light emitting layer is formed through a buffer layer (2) suitable for the substrate. As a result, a semiconductor light emitting device using a Group III nitride compound semiconductor, which is of a vertical type that allows electrodes to be taken out from both of the upper and lower surfaces of a chip, has superior crystalline properties with high light emitting efficiency, and exhibits cleavage, is obtained. Therefore, it is possible to easily mount a LD chip on a sub-mount having a good thermal conductivity, and consequently to prevent a reduction and degradation in the light emitting efficiency (differential quantum efficiency) due to heat.Type: GrantFiled: March 8, 2001Date of Patent: May 11, 2004Assignee: Rohm, Co., LtdInventors: Tetsuhiro Tanabe, Ken Nakahara
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Patent number: 6711198Abstract: A light source device for a laser beam printer in which a semiconductor laser is driven with a pulse current having a minimum pulse width at the ON time on the order of milliseconds or less is provided, wherein the semiconductor laser is formed so that either the rate of change at the rise portion of the pulse current becomes ±8% or less or the semiconductor laser is excited in a multiple mode in the vicinity of the threshold value of the oscillation, and the semiconductor laser oscillates in a single mode at a current separated from the threshold value, by adjusting of at least one of the width w of a stripe groove (7a) of the current block layer, the composition of clad layers (5), the distance d between the current block layer (7) and the active layer (4), the composition of the current block layer (7) and the formation of a light absorption layer into the current block layer (7).Type: GrantFiled: April 14, 2000Date of Patent: March 23, 2004Assignee: Rohm Co. Ltd.Inventors: Jun Ichihara, Hisayoshi Kitajima, Tetsuhiro Tanabe, Ken Nakahara, Haruo Tanaka
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Patent number: 6680959Abstract: When a laminated semiconductor portion of nitride based compound semiconductor is formed so as to constitute a portion forming a light emitting layer forming portion on a sapphire substrate, the sapphire substrate has an off orientation angle having a tilt relative to an A axis or a M axis in such a way that 0.2°≦&thgr;={&thgr;a2+&thgr;m2}1/2≦0.3°, wherein 0°≦&thgr;a≦0.3°, 0°≦&thgr;m≦0.3°, when taking the angle tilted relative to the A axis as &thgr;a and to the M axis as &thgr;m, and the foregoing nitride based compound semiconductor layers are laminated onto the surface of the off-oriented C plane.Type: GrantFiled: July 18, 2001Date of Patent: January 20, 2004Assignee: Rohm Co., Ltd.Inventors: Tetsuhiro Tanabe, Norikazu Ito
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Patent number: 6674098Abstract: A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.Type: GrantFiled: January 25, 2002Date of Patent: January 6, 2004Assignees: National Institute of Advanced Industrial Science and Technology, Rohm Co., Ltd.Inventors: Shigeru Niki, Paul Fons, Kakuya Iwata, Tetsuhiro Tanabe, Hidemi Takasu, Ken Nakahara
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Patent number: 6670204Abstract: A first GaN layer (2) is formed on a substrate (1), mask layer (3) having opening parts (3a) are formed thereon, a second GaN layer (4) is selectively grown in the lateral direction from the opening parts on the mask layer, and further a nitride type compound semiconductor layered part (15) is so laminated as to form a light emitting layer. Recessed parts (3b) are formed in the upper face side of the mask layer. In other words, owing to the recessed parts in the upper face side of the mask layer, the second GaN type compound semiconductor layer (4) is grown as to form approximately parallel gap (3c) between the bottom face of the second GaN type compound semiconductor layer and the mask layer. Further, it is preferable for the mask to be formed in a manner that the opening parts for exposing the seeds are not arranged only continuous in one single direction in the entire surface of the wafer type substrate.Type: GrantFiled: September 6, 2002Date of Patent: December 30, 2003Assignee: Rohm, Co., Ltd.Inventors: Tetsuhiro Tanabe, Masayuki Sonobe
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Publication number: 20030001163Abstract: A first GaN layer (2) is formed on a substrate (1), mask layer (3) having opening parts (3a) are formed thereon, a second GaN layer (4) is selectively grown in the lateral direction from the opening parts on the mask layer, and further a nitride type compound semiconductor layered part (15) is so laminated as to form a light emitting layer. Recessed parts (3b) are formed in the upper face side of the mask layer. In other words, owing to the recessed parts in the upper face side of the mask layer, the second GaN type compound semiconductor layer (4) is grown as to form approximately parallel gap (3c) between the bottom face of the second GaN type compound semiconductor layer and the mask layer. Further, it is preferable for the mask to be formed in a manner that the opening parts for exposing the seeds are not arranged only continuous in one single direction in the entire surface of the wafer type substrate.Type: ApplicationFiled: September 6, 2002Publication date: January 2, 2003Applicant: ROHM CO., LTD.Inventors: Tetsuhiro Tanabe, Masayuki Sonobe
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Patent number: 6469320Abstract: A first GaN layer (2) is formed on a substrate (1), mask layer (3) having opening parts (3a) are formed thereon, a second GaN layer (4) is selectively grown in the lateral direction from the opening parts on the mask layer, and further a nitride type compound semiconductor layered part (15) is so laminated as to form a light emitting layer. Recessed parts (3b) are formed in the upper face side of the mask layer. In other words, owing to the recessed parts in the upper face side of the mask layer, the second GaN type compound semiconductor layer (4) is grown as to form approximately parallel gap (3c) between the bottom face of the second GaN type compound semiconductor layer and the mask layer. Further, it is preferable for the mask to be formed in a manner that the opening parts for exposing the seeds are not arranged only continuous in one single direction in the entire surface of the wafer type substrate.Type: GrantFiled: May 25, 2001Date of Patent: October 22, 2002Assignee: Rohm, Co., Ltd.Inventors: Tetsuhiro Tanabe, Masayuki Sonobe
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Patent number: 6426967Abstract: A semiconductor laser device includes a substrate formed of GaAs. A lower electrode is formed on an underside of this substrate. The substrate has, on its top surface, a lower cladding layer, an active layer, a first upper cladding layer, an etch stop layer, a current restricting layer, a second contact layer and an upper electrode formed in this order. A second upper cladding layer is formed widthwise centrally of the current restricting layer. A first contact layer and an insulation film are formed on the second upper cladding layer. This insulation film blocks a current from flowing from the upper electrode to an end of an optical waveguide. Accordingly, a current non-injection region is provided at an end of the active layer or optical waveguide.Type: GrantFiled: June 25, 1999Date of Patent: July 30, 2002Assignee: Rohm Co., Ltd.Inventor: Tetsuhiro Tanabe
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Publication number: 20020027933Abstract: When a laminated semiconductor portion of nitride based compound semiconductor is formed so as to constitute a portion forming a light emitting layer forming portion on a sapphire substrate, the sapphire substrate has an off orientation angle having a tilt relative to an A axis or a M axis in such a way that 0.2°≦&thgr;={&thgr;a2+&thgr;m2}½≦0.3°, wherein 0°≦&thgr;a≦0.3°, 0°≦&thgr;m≦0.3°, when taking the angle tilted relative to the A axis as &thgr;a and to the M axis as &thgr;m, and the foregoing nitride based compound semiconductor layers are laminated onto the surface of the off-oriented C plane.Type: ApplicationFiled: July 18, 2001Publication date: March 7, 2002Applicant: ROHM CO., LTD.Inventors: Tetsuhiro Tanabe, Norikazu Ito