Abstract: Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces 27, 29 to form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser device 11 has a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface 17a. For this reason, it is feasible to make use of emission by a band transition enabling the low threshold current. In a laser structure 13, a first surface 13a is opposite to a second surface 13b. The first and second fractured faces 27, 29 extend from an edge 13c of the first surface 13a to an edge 13d of the second surface 13b. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.

Abstract: A primary surface 23a of a supporting base 23 of a light-emitting diode 21a tilts by an off-angle of 10 degrees or more and less than 80 degrees from the c-plane. A semiconductor stack 25a includes an active layer having an emission peak in a wavelength range from 400 nm to 550 nm. The tilt angle “A” between the (0001) plane (the reference plane SR3 shown in FIG. 5) of the GaN supporting base and the (0001) plane of a buffer layer 33a is 0.05 degree or more and 2 degrees or less. The tilt angle “B” between the (0001) plane of the GaN supporting base (the reference plane SR4 shown in FIG. 5) and the (0001) plane of a well layer 37a is 0.05 degree or more and 2 degrees or less. The tilt angles “A” and “B” are formed in respective directions opposite to each other with reference to the c-plane of the GaN supporting base.

Abstract: In a III-nitride semiconductor laser device, a laser structure includes a support base with a semipolar primary surface comprised of a III-nitride semiconductor, and a semiconductor region provided on the semipolar primary surface of the support base. First and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device are provided on first and second end faces of the semiconductor region, respectively. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The first cladding layer, the second cladding layer, and the active layer are arranged in an axis normal to the semipolar primary surface.

Abstract: A group III nitride semiconductor optical device includes: a substrate comprising a group III nitride semiconductor; a first group-III nitride semiconductor region on a primary surface of the substrate; a second group-III nitride semiconductor region on the primary surface of the substrate; and an active layer between the first group-III nitride semiconductor region and the second group-III nitride semiconductor region. The primary surface of the substrate tilts at a tilt angle in the range of 63 degrees to smaller than 80 degrees toward the m-axis of the group III nitride semiconductor from a plane perpendicular to a reference axis extending along the c-axis of the group III nitride semiconductor. The first group-III nitride semiconductor region, the active layer, and the second group-III nitride semiconductor region are arranged in the direction of the normal axis to the primary surface of the substrate. The active layer is configured to produce light having a wavelength in the range of 580 nm to 800 nm.

Abstract: In a III-nitride semiconductor laser device, a laser structure includes a support base with a semipolar primary surface comprised of a III-nitride semiconductor, and a semiconductor region provided on the semipolar primary surface of the support base. First and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device are provided on first and second end faces of the semiconductor region, respectively. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The first cladding layer, the second cladding layer, and the active layer are arranged in an axis normal to the semipolar primary surface.

Abstract: A method of making a semiconductor light-emitting device involves the steps of selecting at least one tilt angle for a primary surface of a substrate to evaluate the direction of piezoelectric polarization in a light-emitting layer, the substrate comprising a group III nitride semiconductor; preparing a substrate having the primary surface, the primary surface having the selected tilt angle, and the primary surface comprising the group III nitride semiconductor; forming a quantum well structure and p- and n-type gallium nitride semiconductor layers for the light-emitting layer at the selected tilt angle to prepare a substrate product; measuring photoluminescence of the substrate product while applying a bias to the substrate product, to determine bias dependence of the photoluminescence; evaluating the direction of the piezoelectric polarization in the light-emitting layer at the selected tilt angle on the primary surface of the substrate by the determined bias dependence; determining which of the primary sur

Abstract: A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon.

Abstract: In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle ? is in the range of greater than 59 degrees to less than 80 degrees or greater than 150 degrees to less than 180 degrees. A gallium nitride based semiconductor layer P is adjacent to a light-emitting layer SP? with a negative piezoelectric field and has a band gap larger than that of a barrier layer. The direction of the piezoelectric field in the well layer W3 is directed in a direction from the n-type layer to the p-type layer, and the piezoelectric field in the gallium nitride based semiconductor layer P is directed in a direction from the p-type layer to the n-type layer. Consequently, the valence band, not the conduction band, has a dip at the interface between the light-emitting layer SP? and the gallium nitride based semiconductor layer P.

Abstract: A group-III nitride semiconductor laser device comprises a laser structure including a support base and a semiconductor region, and an electrode provided on the semiconductor region of the laser structure. The support base comprises a hexagonal group-III nitride semiconductor and has a semipolar primary surface, and the semiconductor region is provided on the semipolar primary surface of the support base. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer. The first cladding layer, the second cladding layer, and the active layer are arranged along a normal axis to the semipolar primary surface. The active layer comprises a gallium nitride-based semiconductor layer.

Abstract: In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle ? is in the range of greater than 59 degrees to less than 80 degrees or greater than 150 degrees to less than 180 degrees. A gallium nitride based semiconductor layer P is adjacent to a light-emitting layer SP? with a negative piezoelectric field and has a band gap larger than that of a barrier layer. The direction of the piezoelectric field in the well layer W3 is directed in a direction from the n-type layer to the p-type layer, and the piezoelectric field in the gallium nitride based semiconductor layer P is directed in a direction from the p-type layer to the n-type layer. Consequently, the valence band, not the conduction band, has a dip at the interface between the light-emitting layer SP? and the gallium nitride based semiconductor layer P.

Abstract: An object is to provide a nitride-based semiconductor light emitting device capable of preventing a Schottky barrier from being formed at an interface between a contact layer and an electrode. LD 1 is provided as a nitride-based semiconductor light emitting device provided with a GaN substrate 3, a hexagonal GaN-based semiconductor region 5 provided on a primary surface S1 of the GaN substrate 3 and including a light emitting layer 11, and a p-electrode 21 provided on the GaN-based semiconductor region 5 and comprised of metal. The GaN-based semiconductor region 5 includes a contact layer 17 involving strain, the contact layer 17 is in contact with the p-electrode, the primary surface S1 extends along a reference plane S5 inclined at a predetermined inclination angle ? from a plane perpendicular to the c-axis direction of the GaN substrate 3, and the inclination angle ? is either in the range of more than 40° and less than 90° or in the range of not less than 150° and less than 180°.

Abstract: A group III nitride substrate has a semi-polar primary surface. A first cladding layer has a first conductivity type, and comprises aluminum-containing group III nitride. The first cladding layer is provided on the substrate. An active layer is provided on the first cladding layer. A second cladding layer has a second conductivity type, and comprises aluminum-containing group III nitride. The second cladding layer is provided on the active layer. An optical guiding layer is provided between the first cladding layer and the active layer and/or between the second cladding layer and the active layer. The optical guiding layer comprises a first layer comprising Inx1Ga1-x1N (0?x1<1) and a second layer comprising Inx2Ga1-x2N (x1<x2<1). The second layer is provided between the first layer and the active layer. The total thickness of the first layer and the second layer is greater than 0.1 ?m. The wavelength of laser light is in a range of 480 nm to 550 nm.

Abstract: Provided is a III-nitride semiconductor laser diode capable of lasing to emit light of not less than 500 nm with use of a semipolar plane. Since an active layer 29 is provided so as to generate light at the wavelength of not less than 500 nm, the wavelength of light to be confined into a core semiconductor region 19 is a long wavelength. A first optical guide layer 27 is provided with a two-layer structure, and a second optical guide layer 31 is provided with a two-layer structure.

Abstract: A primary surface 23a of a supporting base 23 of a light-emitting diode 21a tilts by an off-angle of 10 degrees or more and less than 80 degrees from the c-plane. A semiconductor stack 25a includes an active layer having an emission peak in a wavelength range from 400 nm to 550 nm. The tilt angle “A” between the (0001) plane (the reference plane SR3 shown in FIG. 5) of the GaN supporting base and the (0001) plane of a buffer layer 33a is 0.05 degree or more and 2 degrees or less. The tilt angle “B” between the (0001) plane of the GaN supporting base (the reference plane SR4 shown in FIG. 5) and the (0001) plane of a well layer 37a is 0.05 degree or more and 2 degrees or less. The tilt angles “A” and “B” are formed in respective directions opposite to each other with reference to the c-plane of the GaN supporting base.

Abstract: In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle ? is in the range of greater than 59 degrees to less than 80 degrees or greater than 150 degrees to less than 180 degrees. A gallium nitride based semiconductor layer P is adjacent to a light-emitting layer SP? with a negative piezoelectric field and has a band gap larger than that of a barrier layer. The direction of the piezoelectric field in the well layer W3 is directed in a direction from the n-type layer to the p-type layer, and the piezoelectric field in the gallium nitride based semiconductor layer P is directed in a direction from the p-type layer to the n-type layer. Consequently, the valence band, not the conduction band, has a dip at the interface between the light-emitting layer SP? and the gallium nitride based semiconductor layer P.

Abstract: Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces 27, 29 to form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser device 11 has a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface 17a. For this reason, it is feasible to make use of emission by a band transition enabling the low threshold current. In a laser structure 13, a first surface 13a is opposite to a second surface 13b. The first and second fractured faces 27, 29 extend from an edge 13c of the first surface 13a to an edge 13d of the second surface 13b. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.

Abstract: In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle ? is in the range of greater than 59 degrees to less than 80 degrees or greater than 150 degrees to less than 180 degrees. A gallium nitride based semiconductor layer P is adjacent to a light-emitting layer SP? with a negative piezoelectric field and has a band gap larger than that of a barrier layer. The direction of the piezoelectric field in the well layer W3 is directed in a direction from the n-type layer to the p-type layer, and the piezoelectric field in the gallium nitride based semiconductor layer P is directed in a direction from the p-type layer to the n-type layer. Consequently, the valence band, not the conduction band, has a dip at the interface between the light-emitting layer SP? and the gallium nitride based semiconductor layer P.

Abstract: A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon.

Abstract: In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle ? is in the range of greater than 59 degrees to less than 80 degrees or greater than 150 degrees to less than 180 degrees. A gallium nitride based semiconductor layer P is adjacent to a light-emitting layer SP? with a negative piezoelectric field and has a band gap larger than that of a barrier layer. The direction of the piezoelectric field in the well layer W3 is directed in a direction from the n-type layer to the p-type layer, and the piezoelectric field in the gallium nitride based semiconductor layer P is directed in a direction from the p-type layer to the n-type layer. Consequently, the valence band, not the conduction band, has a dip at the interface between the light-emitting layer SP? and the gallium nitride based semiconductor layer P.

Abstract: In a GaN based semiconductor optical device 11a, the primary surface 13a of the substrate 13 tilts at a tilting angle toward an m-axis direction of the first GaN based semiconductor with respect to a reference axis “Cx” extending in a direction of a c-axis of the first GaN based semiconductor, and the tilting angle is 63 degrees or more, and is less than 80 degrees. The GaN based semiconductor epitaxial region 15 is provided on the primary surface 13a. On the GaN based semiconductor epitaxial region 15, an active layer 17 is provided. The active layer 17 includes one semiconductor epitaxial layer 19. The semiconductor epitaxial layer 19 is composed of InGaN. The thickness direction of the semiconductor epitaxial layer 19 tilts with respect to the reference axis “Cx.” The reference axis “Cx” extends in the direction of the [0001] axis. This structure provides the GaN based semiconductor optical device that can reduces decrease in light emission characteristics due to the indium segregation.