Abstract: Provided is a group-III nitride semiconductor laser device with a laser cavity of high lasing yield, 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 to form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser device has a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface. In a laser structure, a first surface is opposite to a second surface. The first and second fractured faces extend from an edge of the first surface to an edge of the second surface. 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: Provided is a method of fabricating a gallium nitride semiconductor which enables activation of a p-type dopant with a heat treatment performed for a relatively short period of time. The fabricating method comprises the step of performing, in a vacuum, a heat treatment of a group III nitride semiconductor region, the group III nitride semiconductor region comprising a gallium nitride semiconductor, the gallium nitride semiconductor including a p-type dopant, the a group III nitride semiconductor region having a group III nitride semiconductor surface inclined with respect to a reference plane perpendicular to a reference axis, and the reference axis extending in a direction of a c-axis of the gallium nitride semiconductor.

Abstract: Provided is a III-nitride semiconductor laser allowing for provision of a low threshold with use of a semipolar plane. A primary surface 13a of a semiconductor substrate 13 is inclined at an angle of inclination AOFF in the range of not less than 50 degrees and not more than 70 degrees toward the a-axis direction of GaN with respect to a reference plane perpendicular to a reference axis Cx along the c-axis direction of GaN. A first cladding layer 15, an active layer 17, and a second cladding layer 19 are provided on the primary surface 13a of the semiconductor substrate 13. The well layers 23a of the active layer 17 comprise InGaN. A polarization degree P in the LED mode of emission from the active layer of the semiconductor laser that reaches lasing is not less than ?1 and not more than 0.1.

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. 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 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 III-nitride semiconductor laser device includes a laser structure including a support base, a semiconductor region, and an electrode. The support base includes a hexagonal III-nitride semiconductor and a semipolar primary surface. The semiconductor region includes first and second cladding layers and an active layer arranged along an axis normal to the semipolar primary surface. A c-axis of the hexagonal III-nitride semiconductor is inclined at an angle ALPHA with respect to the normal axis toward an m-axis of the hexagonal III-nitride semiconductor. The laser structure includes first and second fractured faces that intersect with an m-n plane defined by the normal axis and the m-axis of the hexagonal III-nitride semiconductor. A laser cavity of the laser device includes the first and second fractured faces. Each of the first and second fractured faces have a stripe structure on an end face of the support base.

Abstract: A method of fabricating a III-nitride semiconductor laser device includes: preparing a substrate with a semipolar primary surface, the semipolar primary surface including a hexagonal III-nitride semiconductor; forming a substrate product having a laser structure, an anode electrode, and a cathode electrode, the laser structure including a substrate and a semiconductor region, and the semiconductor region being formed on the semipolar primary surface; after forming the substrate product, forming first and second end faces; and forming first and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device on the first and second end faces, respectively.

Abstract: A nitride semiconductor light emitting device is provided. A core semiconductor region, a first cladding region, and a second cladding region are mounted on a nonpolar primary surface of a support substrate of GaN which is not the polar plane. The core semiconductor region includes an active layer and a carrier block layer. The first cladding region includes an n-type AlGaN cladding layer and an n-type InAlGaN cladding layer. The n-type InAlGaN cladding layer is provided between the n-type AlGaN cladding layer and the active layer. A misfit dislocation density at an interface is larger than that at an interface. The AlGaN cladding layer is lattice-relaxed with respect to the GaN support substrate and the InAlGaN cladding layer is lattice-relaxed with respect to the AlGaN cladding layer.

Abstract: A source gas flows through a flow channel 23 of a metal-organic vapor phase epitaxy reactor 21. The source gas is fed in a direction across a main surface 25a of a susceptor 25. GaN substrates 27a to 27c are placed on the susceptor main surface 25a. An off-angle monotonically varies on a line segment extending from one point on the edges of the main surfaces of the gallium nitride substrates 27a to 27c to another point on the edges. The orientations of the GaN substrates 27a to 27c are represented by the orientations of the orientation flats. By placing the plurality of gallium nitride substrates 27a to 27c on the susceptors 25 of the metal-organic vapor phase epitaxy reactor 21 in these orientations, the influence of the off-angle distribution can be reduced by using the influence originated from the flow of the source gas.

Abstract: A III-nitride semiconductor laser device is provided with a laser structure and an electrode. The laser structure includes a support base which includes a hexagonal III-nitride semiconductor and a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface. The electrode is provided on the semiconductor region. The semiconductor region includes a first cladding layer of a first conductivity type GaN-based semiconductor, a second cladding layer of a second conductivity type GaN-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer.

Abstract: Provided is a gallium nitride based semiconductor light-emitting device with a structure capable of enhancing the degree of polarization. A light-emitting diode 11a is provided with a semiconductor region 13, an InGaN layer 15 and an active layer 17. The semiconductor region 13 has a primary surface 13a having semipolar nature, and is made of GaN or AlGaN. The primary surface 13a of the semiconductor region 13 is inclined at an angle ? with respect to a plane Sc perpendicular to a reference axis Cx which extends in a direction of the [0001] axis in the primary surface 13a. The thickness D13 of the semiconductor region 13 is larger than the thickness DInGaN of the InGaN layer 17, and the thickness DInGaN of the InGaN layer 15 is not less than 150 nm. The InGaN layer 15 is provided directly on the primary surface 13a of the semiconductor region 13 and is in contact with the primary surface 13a.

Abstract: A III-nitride semiconductor device has a support base comprised of a III-nitride semiconductor and having a primary surface extending along a first reference plane perpendicular to a reference axis inclined at a predetermined angle with respect to a c-axis of the III-nitride semiconductor, and an epitaxial semiconductor region provided on the primary surface of the support base. The epitaxial semiconductor region includes GaN-based semiconductor layers. The reference axis is inclined at a first angle from the c-axis of the III-nitride semiconductor toward a first crystal axis, either the m-axis or a-axis. The reference axis is inclined at a second angle from the c-axis of the III-nitride semiconductor toward a second crystal axis, the other of the m-axis and a-axis. Morphology of an outermost surface of the epitaxial semiconductor region includes a plurality of pits. A pit density of the pits is not more than 5×104 cm?2.

Abstract: Provided is a Group III nitride semiconductor laser diode with a cladding layer capable of providing high optical confinement and carrier confinement. An n-type Al0.08Ga0.92N cladding layer is grown so as to be lattice-relaxed on a (20-21)-plane GaN substrate. A GaN optical guiding layer is grown so as to be lattice-relaxed on the n-type cladding layer. An active layer, a GaN optical guiding layer, an Al0.12Ga0.88N electron blocking layer, and a GaN optical guiding layer are grown so as not to be lattice-relaxed on the optical guiding layer. A p-type Al0.08Ga0.92N cladding layer is grown so as to be lattice-relaxed on the optical guiding layer. A p-type GaN contact layer is grown so as not to be lattice-relaxed on the p-type cladding layer, to produce a semiconductor laser. Dislocation densities at junctions are larger than those at the other junctions.

Abstract: Method of high-yield manufacturing superior semiconductor devices includes: a step of preparing a GaN substrate having a ratio St/S—of collective area (St cm2) of inversion domains in, to total area (S cm2) of the principal face of, the GaN substrate—of no more than 0.5, with the density along the (0001) Ga face, being the substrate principal face, of inversion domains whose surface area where the polarity in the [0001] direction is inverted with respect to the principal domain (matrix) is 1 ?m2 or more being D cm?2; and a step of growing on the GaN substrate principal face an at least single-lamina semiconductor layer to form semiconductor devices in which the product Sc×D of the area Sc of the device principal faces, and the density D of the inversion domains is made less than 2.3.

Abstract: A nitride semiconductor device includes a main surface and an indicator portion. The main surface is a plane inclined by at least 71° and at most 79° in a [1-100] direction from a (0001) plane or a plane inclined by at least 71° and at most 79° in a [?1100] direction from a (000-1) plane. The indicator portion indicates a (?1017) plane, a (10-1-7) plane, or a plane inclined by at least ?4° and at most 4° in the [1-100] direction from these planes and inclined by at least ?0.5° and at most 0.5° in a direction orthogonal to the [1-100] direction.

Abstract: A nitride semiconductor device includes a main surface and an indicator portion. The main surface is a plane inclined by at least 71° and at most 79° in a [1-100] direction from a (0001) plane or a plane inclined by at least 71° and at most 79° in a [?1100] direction from a (000-1) plane. The indicator portion indicates a (?1017) plane, a (10-1-7) plane, or a plane inclined by at least ?4° and at most 4° in the [1-100] direction from these planes and inclined by at least ?0.5° and at most 0.5° in a direction orthogonal to the [1-100] direction.

Abstract: A method of fabricating a III-nitride semiconductor laser device includes: preparing a substrate product, where the substrate product has a laser structure, the laser structure includes a semiconductor region and a substrate of a hexagonal III-nitride semiconductor, the substrate has a semipolar primary surface, and the semiconductor region is formed on the semipolar primary surface; scribing a first surface of the substrate product to form a scribed mark, the scribed mark extending in a direction of an a-axis of the hexagonal III-nitride semiconductor; and after forming the scribed mark, carrying out breakup of the substrate product by press against a second region of the substrate product while supporting a first region of the substrate product but not supporting the second region thereof, to form another substrate product and a laser bar.

Abstract: A nitride-based semiconductor light-emitting device having enhanced efficiency of carrier injection to a well layer is provided. The nitride-based semiconductor light-emitting device comprises a hexagonal gallium nitride-based semiconductor substrate 5, an n-type gallium nitride-based semiconductor region 7 disposed on the principal surface S1 of the substrate 5, a light-emitting layer 11 having a single-quantum-well structure disposed on the n-type gallium nitride-based semiconductor region 7, and a p-type gallium nitride-based semiconductor region 19 disposed on the light-emitting layer 11. The light-emitting layer 11 is disposed between the n-type gallium nitride-based semiconductor region 7 and the p-type gallium nitride-based semiconductor region 19. The light-emitting layer 11 includes a well layer 15 and barrier layers 13 and 17. The well layer 15 comprises InGaN.

Abstract: In a III-nitride semiconductor laser device, a laser structure includes a support base comprised of a hexagonal III-nitride semiconductor and having a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface of the support base. An electrode is provided on the semiconductor region of the laser structure. The c-axis of the hexagonal III-nitride semiconductor of the support base is inclined at an angle ALPHA with respect to a normal axis toward the m-axis of the hexagonal III-nitride semiconductor. The angle ALPHA is in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees. The laser structure includes first and second fractured faces that intersect with an m-n plane defined by the m-axis of the hexagonal III-nitride semiconductor and the normal axis. A laser cavity of the III-nitride semiconductor laser device includes the first and second fractured faces.

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: A method of fabricating a group-III nitride semiconductor laser device includes: preparing a substrate of a hexagonal group-III nitride semiconductor, where the substrate has a semipolar primary surface; forming a substrate product having a laser structure, an anode electrode and a cathode electrode, where the laser structure includes the substrate and a semiconductor region, and where the semiconductor region is formed on the semipolar primary surface; scribing a first surface of the substrate product in part in a direction of the a-axis of the hexagonal group-III nitride semiconductor; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.