Abstract: A method of fabricating a III-nitride semiconductor laser device includes: preparing a substrate having a hexagonal III-nitride semiconductor and having a semipolar primary surface; 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 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 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.

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.

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 includes a group III nitride semiconductor supporting base, a GaN based semiconductor region, an active layer, and a GaN semiconductor region. The primary surface of the group III nitride semiconductor supporting base is not any polar plane, and forms a finite angle with a reference plane that is orthogonal to a reference axis extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region, grown on the semipolar primary surface, includes a semiconductor layer of, for example, an n-type GaN based semiconductor doped with silicon. A GaN based semiconductor layer of an oxygen concentration of 5×1016 cm?3 or more provides an active layer, grown on the primary surface, with an excellent crystal quality.

Abstract: In the nitride based semiconductor optical device, the strained well layers extend along a reference plane tilting at a tilt angle ? from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. A gallium nitride based semiconductor layer is adjacent to a light-emitting layer 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 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 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 and the gallium nitride based semiconductor layer.

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: Provided are a group-III nitride semiconductor laser device with a laser cavity to enable a low threshold current on a semipolar surface of a hexagonal group-III nitride, and a method for fabricating the group-III nitride semiconductor laser device on a stable basis. Notches, e.g., notch 113a and others, are formed at four respective corners of a first surface 13a located on the anode side of a group-III nitride semiconductor laser device 11. The notch 113a or the like is a part of a scribed groove provided for separation of the device 11. The scribed grooves are formed with a laser scriber and the shape of the scribed grooves is adjusted by controlling the laser scriber. For example, a ratio of the depth of the notch 113a or the like to the thickness of the group-III nitride semiconductor laser device 11 is not less than 0.05 and not more than 0.

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 method for forming a quantum well structure that can reduce the variation in the In composition in the thickness direction of a well layer and a method for manufacturing a semiconductor light emitting element are provided. In a step of forming a quantum well structure (active layer) by alternately growing barrier layers and well layers on a primary surface of a GaN substrate, the well layers are each formed by growing InGaN, the barrier layers are each grown at a first temperature, the well layers are each grown at a second temperature which is lower than that of the first temperature, and when the well layers are each formed, before a starting material gas for Ga (trimethylgallium) is supplied, a starting material gas for In is supplied.

Abstract: Provided is a group-III nitride semiconductor laser device with a laser cavity enabling a low threshold current, on a semipolar surface of a support base the c-axis of a hexagonal group-III nitride of which tilts toward the m-axis. In a laser structure 13, a first surface 13a is a surface opposite to a second surface 13b and first and second fractured faces 27, 29 extend each from an edge 13c of the first surface 13a to an edge 13d of the second surface 13b. A scribed mark SM1 extending from the edge 13c to the edge 13d is made, for example, at one end of the first fractured face 27, and the scribed mark SM1 or the like has a depressed shape extending from the edge 13c to the edge 13d. The fractured faces 27, 29 are not formed by dry etching and thus are different from the conventional cleaved facets such as c-planes, en-planes, or a-planes. It is feasible to use emission of a band transition enabling a low threshold current.

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 for fabricating a III-nitride semiconductor laser device includes: forming a substrate product having a laser structure; scribing a first surface of the substrate product to form a scribed mark, which extends along a reference line indicative of a direction of the a-axis of the hexagonal III-nitride semiconductor, on the first surface, a scribed mark; mounting the substrate product on a breaking device to support first and second regions of the substrate product by first and second support portions, respectively, of the breaking device; and carrying out breakup of the substrate product by press in alignment with the scribed mark in a third region, without supporting the third region of the substrate product located between the first and second regions, to form another substrate product and a laser bar. First and second end faces of the laser bar form a laser cavity of the III-nitride semiconductor laser device.

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 nitride semiconductor light emitting device including a light emitting layer above a GaN support base with a semipolar surface and allowing for suppression of reduction in luminous efficiency due to misfit dislocations. A nitride semiconductor light emitting device 11 has a support base 13 comprised of a hexagonal gallium nitride, an n-type gallium nitride-based semiconductor layer 15 including an InX1AlY1Ga1-X1-Y1N (0<X1<1, 0<Y1<1, X1+Y1<1) layer 21, a light emitting layer 17, and a p-type gallium nitride-based semiconductor layer 19. This InAlGaN layer 21 is provided between a semipolar primary surface 13a and the light emitting layer 17. Since the bandgap E of the InAlGaN layer 21 is not less than the bandgap E of gallium nitride, a confinement effect of carriers and light in the light emitting layer 17 is provided.

Abstract: Provided are a group-III nitride semiconductor laser device with a laser cavity to enable a low threshold current on a semipolar surface of a hexagonal group-III nitride, and a method for fabricating the group-III nitride semiconductor laser device on a stable basis. Notches, e.g., notch 113a and others, are formed at four respective corners of a first surface 13a located on the anode side of a group-III nitride semiconductor laser device 11. The notch 113a or the like is a part of a scribed groove provided for separation of the device 11. The scribed grooves are formed with a laser scriber and the shape of the scribed grooves is adjusted by controlling the laser scriber. For example, a ratio of the depth of the notch 113a or the like to the thickness of the group-III nitride semiconductor laser device 11 is not less than 0.05 and not more than 0.

Abstract: In the method for fabricating a III-nitride semiconductor laser device, a substrate product is formed, and the substrate product has a laser structure including a substrate that is made of a hexagonal III-nitride semiconductor and has a semipolar primary surface, and the semiconductor region is formed on the semipolar primary surface, and thereafter a first surface of the substrate product is scribed to form a scribed mark extending in a direction of the a-axis of the hexagonal III-nitride semiconductor. After forming the scribed mark, breakup of the substrate product is carried out 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. This step results in forming another substrate product and a laser bar. The substrate product is divided into two, the first region and the second region, by a predetermined reference line, and the first and second regions are adjacent to each other.

Abstract: A method for fabricating a III-nitride semiconductor laser device includes: forming a substrate product having a laser structure; scribing a first surface of the substrate product to form a scribed mark, which extends along a reference line indicative of a direction of the a-axis of the hexagonal III-nitride semiconductor, on the first surface, a scribed mark; mounting the substrate product on a breaking device to support first and second regions of the substrate product by first and second support portions, respectively, of the breaking device; and carrying out breakup of the substrate product by press in alignment with the scribed mark in a third region, without supporting the third region of the substrate product located between the first and second regions, to form another substrate product and a laser bar. First and second end faces of the laser bar form a laser cavity of the III-nitride semiconductor laser device.

Abstract: Provided is a group-III nitride semiconductor laser device with a laser cavity enabling a low threshold current, on a semipolar surface of a support base the c-axis of a hexagonal group-III nitride of which tilts toward the m-axis. In a laser structure 13, a first surface 13a is a surface opposite to a second surface 13b and first and second fractured faces 27, 29 extend each from an edge 13c of the first surface 13a to an edge 13d of the second surface 13b. A scribed mark SM1 extending from the edge 13c to the edge 13d is made, for example, at one end of the first fractured face 27, and the scribed mark SM1 or the like has a depressed shape extending from the edge 13c to the edge 13d. The fractured faces 27, 29 are not formed by dry etching and thus are different from the conventional cleaved facets such as c-planes, m-planes, or a-planes. It is feasible to use emission of a band transition enabling a low threshold current.

Abstract: Provided are a group-III nitride semiconductor laser device with a laser cavity to enable a low threshold current on a semipolar surface of a hexagonal group-III nitride, and a method for fabricating the group-III nitride semiconductor laser device on a stable basis. Notches, e.g., notch 113a and others, are formed at four respective corners of a first surface 13a located on the anode side of a group-III nitride semiconductor laser device 11. The notch 113a or the like is a part of a scribed groove provided for separation of the device 11. The scribed grooves are formed with a laser scriber and the shape of the scribed grooves is adjusted by controlling the laser scriber. For example, a ratio of the depth of the notch 113a or the like to the thickness of the group-III nitride semiconductor laser device 11 is not less than 0.05 and not more than 0.

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.