Patents by Inventor Michinari Sassa
Michinari Sassa 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).
-
Publication number: 20140239313Abstract: A method of producing a light-emitting semiconductor device of a group III nitride compound includes forming a buffer layer on a sapphire substrate, forming a Si-doped N+-layer with supplying silane, the N+-layer satisfying formula (Alx3Ga1-x3)y3In1-y3N, wherein 0?x3?1, 0?y3?1 and 0?x3+y3?1, forming an emission layer of a group III nitride compound semiconductor satisfying formula Alx1Gay1In1-x1-y1N, where 0?x1?1, 0?y1?1, and 0?x1+y1?1, on the N+-layer, and forming a P-layer of a P-type conduction on the emission layer, the P-layer including aluminum gallium nitride satisfying formula Alx2Ga1-x2N, wherein 0?x2?1.Type: ApplicationFiled: May 2, 2014Publication date: August 28, 2014Applicant: TOYODA GOSEI Co., LTD.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Publication number: 20120217510Abstract: A method of producing a light-emitting semiconductor device of a group III nitride compound includes forming a high carrier concentration N+-layer satisfying the formula (Alx3Ga1-x3)y3In1-y3N, wherein 0?x3?1, 0?y3?1 and 0?x3+y3?1, forming an emission layer of a group III nitride compound semiconductor satisfying the formula, Alx1Gay1In1-x1-y1N, where 0?x1?1, 0?y1?1 and 0?x1+y1?1 on the high carrier concentration layer N+-layer, and forming a P-layer of a P-type conduction, on the emission layer, the P-layer including aluminum gallium nitride satisfying the formula Alx2Ga1-x2N, wherein 0?x2?1.Type: ApplicationFiled: May 10, 2012Publication date: August 30, 2012Applicant: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Publication number: 20110101412Abstract: A method of producing a light-emitting semiconductor device of a group III nitride compound includes forming an N-layer of an N-type conduction, the N-layer comprising gallium nitride, forming a high carrier concentration N+-layer satisfying the formula (Alx3Ga1-x3)y3In1-y3N, wherein 0?x3?1, 0?y3?1 and 0?x3+y3?1, on the N-layer, forming an emission layer of a group III nitride compound semiconductor satisfying the formula, Alx1Gay1In1-x1-y1N, where 0?x1?1, 0?y1?1 and 0?x1+y1?1 on the high carrier concentration layer N+layer, doping Si and Zn into the emission layer, forming a P-layer of a P-type conduction, on the emission layer, the P-layer including aluminum gallium nitride satisfying the formula Alx2Ga1-x2N, wherein 0?x2?1, and forming a contact layer of a P-type conduction, on the P-type layer, the contact layer including gallium nitride.Type: ApplicationFiled: January 10, 2011Publication date: May 5, 2011Applicant: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 7867800Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1?x3)y3In1?y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1?x2)y2In1?y2N emission layer (5), and a Mg-doped (Alx1Ga1?x1)y1In1?y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: GrantFiled: December 20, 2007Date of Patent: January 11, 2011Assignee: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Publication number: 20080173880Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: ApplicationFiled: December 20, 2007Publication date: July 24, 2008Applicant: Toyoda GoseiInventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 7332366Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: GrantFiled: January 10, 2006Date of Patent: February 19, 2008Assignee: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 7138286Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: GrantFiled: June 3, 2005Date of Patent: November 21, 2006Assignee: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Publication number: 20060118821Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: ApplicationFiled: January 10, 2006Publication date: June 8, 2006Applicant: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 7001790Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: GrantFiled: February 15, 2001Date of Patent: February 21, 2006Assignee: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 6984536Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1?xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1?xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1?xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semiconductor (AlxGa1?xN) haType: GrantFiled: January 23, 2002Date of Patent: January 10, 2006Assignees: Toyoda Gosei Co., Ltd., Japan Science and Technology Agency, Nagoya UniversityInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Publication number: 20050224834Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 ? thickness. The GaN n+-layer (3) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 ?m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 ?m thickness. The p-layer 6 has about a 1.0 ?m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: ApplicationFiled: June 3, 2005Publication date: October 13, 2005Applicant: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 6830992Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1−xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1−xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1−xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semicType: GrantFiled: October 2, 2000Date of Patent: December 14, 2004Assignees: Toyoda Gosei Co., Ltd., Nagoya University, Japan Science and Technology CorporationInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Patent number: 6607595Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlXGa1-xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1-XN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1-xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semiconductor (AlxGa1-xType: GrantFiled: October 2, 2000Date of Patent: August 19, 2003Assignees: Toyoda Gosei Co., Ltd., Kabushiki Kaisha Toyota Chuo Kenkyu sho, Nagoya University, Japan Science and Technology CorporationInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hasimoto, Isamu Akasaki
-
Patent number: 6593599Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1−xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1−xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1−xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semicType: GrantFiled: October 14, 1999Date of Patent: July 15, 2003Assignees: Japan Science and Technology Corporation, Toyoda Gosei Co., Ltd., Nagoya UniversityInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Patent number: 6472689Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1−xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1−xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1−xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semicType: GrantFiled: October 2, 2000Date of Patent: October 29, 2002Assignees: Toyoda Gosei Co., Ltd., Nagoya University, Japan Science and Technology CorporationInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Patent number: 6472690Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1−xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1−xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1−xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semicType: GrantFiled: October 2, 2000Date of Patent: October 29, 2002Assignees: Toyoda Gosei Co., Ltd., Nagoya University, Japan Science and Technology CorporationInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Publication number: 20020060326Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1-xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1-xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1-xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semiconductor (AlxGa1-xType: ApplicationFiled: January 23, 2002Publication date: May 23, 2002Inventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Patent number: 6362017Abstract: Disclosed herein are (1) a light-emitting semiconductor device that uses a gallium nitride compound semiconductor (AlxGa1−xN) in which the n-layer of n-type gallium nitride compound semiconductor (AlxGa1−xN) is of double-layer structure including an n-layer of low carrier concentration and an n+-layer of high carrier concentration, the former being adjacent to the i-layer of insulating gallium nitride compound semiconductor (AlxGa1−xN); (2) a light-emitting semiconductor device of similar structure as above in which the i-layer is of double-layer structure including an iL-layer of low impurity concentration containing p-type impurities in comparatively low concentration and an iH-layer of high impurity concentration containing p-type impurities in comparatively high concentration, the former being adjacent to the n-layer; (3) a light-emitting semiconductor device having both of the above-mentioned features and (4) a method of producing a layer of an n-type gallium nitride compound semicType: GrantFiled: June 2, 2000Date of Patent: March 26, 2002Assignees: Toyoda Gosei Co., Ltd., Nagoya University, Japan Science and Technology CorporationInventors: Katsuhide Manabe, Akira Mabuchi, Hisaki Kato, Michinari Sassa, Norikatsu Koide, Shiro Yamazaki, Masafumi Hashimoto, Isamu Akasaki
-
Publication number: 20010019849Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1-x3)y3In1-y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1-x2)y2In1-y2N emission layer (5), and a Mg-doped (Alx1Ga1-x1)y1In1-y1N p-layer (6). The AlN layer (2) has a 500 Å thickness. The GaN n+-layer (3) has about a 2.0 &mgr;m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 &mgr;m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 &mgr;m thickness. The p-layer 6 has about a 1.0 &mgr;m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: ApplicationFiled: February 15, 2001Publication date: September 6, 2001Applicant: TOTODA GOSEI CO. LTD.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike
-
Patent number: 6265726Abstract: A light-emitting semiconductor device (10) consecutively includes a sapphire substrate (1), an AlN buffer layer (2), a silicon (Si) doped GaN n+-layer (3) of high carrier (n-type) concentration, a Si-doped (Alx3Ga1−x3)y3In1−y3N n+-layer (4) of high carrier (n-type) concentration, a zinc (Zn) and Si-doped (Alx2Ga1−x2)y2In1−y2N emission layer (5), and a Mg-doped (Alx1Ga1−x1)y1In1−y1N p-layer (6). The AlN layer (2) has a 500 Å thickness. The GaN n+-layer (3) has about a 2.0 &mgr;m thickness and a 2×1018/cm3 electron concentration. The n+-layer (4) has about a 2.0 &mgr;m thickness and a 2×1018/cm3 electron concentration. The emission layer (5) has about a 0.5 &mgr;m thickness. The p-layer 6 has about a 1.0 &mgr;m thickness and a 2×1017/cm3 hole concentration. Nickel electrodes (7, 8) are connected to the p-layer (6) and n+-layer (4), respectively. A groove (9) electrically insulates the electrodes (7, 8).Type: GrantFiled: August 24, 1999Date of Patent: July 24, 2001Assignee: Toyoda Gosei Co., Ltd.Inventors: Katsuhide Manabe, Hisaki Kato, Michinari Sassa, Shiro Yamazaki, Makoto Asai, Naoki Shibata, Masayoshi Koike