Abstract: A Group III nitride semiconductor laser device includes a laser structure including a support substrate with a semipolar primary surface of a hexagonal Group III nitride semiconductor, and a semiconductor region thereon, and an electrode, provided on the semiconductor region, extending in a direction of a waveguide axis in the laser device. The c-axis of the nitride semiconductor is inclined at an angle ALPHA relative to a normal axis to the semipolar surface toward the waveguide axis direction. The laser structure includes first and second fractured faces intersecting with the waveguide axis. A laser cavity of the laser device includes the first and second fractured faces extending from edges of first and second faces. The first fractured face includes a step provided at an end face of an InGaN layer of the semiconductor region and extending in a direction from one side face to the other of the laser device.

Abstract: A group III nitride semiconductor optical device 11a has a group III nitride semiconductor substrate 13 having a main surface 13a forming a finite angle with a reference plane Sc orthogonal to a reference axis Cx extending in a c-axis direction of the group III nitride semiconductor and an active layer 17 of a quantum-well structure, disposed on the main surface 13a of the group III nitride semiconductor substrate 13, including a well layer 28 made of a group III nitride semiconductor and a plurality of barrier layers 29 made of a group III nitride semiconductor. The main surface 13a exhibits semipolarity. The active layer 17 has an oxygen content of at least 1×1017 cm?3 but not exceeding 8×1017 cm?3. The plurality of barrier layers 29 contain an n-type impurity other than oxygen by at least 1×1017 cm?3 but not exceeding 1×1019 cm?3 in an upper near-interface area 29u in contact with a lower interface 28Sd of the well layer 28 on the group III nitride semiconductor substrate side.

Abstract: A nitride semiconductor laser comprises a conductive support base having a primary surface of gallium nitride based semiconductor, an active layer on the primary surface, and a p-type cladding region on the primary surface. The primary surface is tilted to a reference plane perpendicular to a reference axis extending in the c-axis direction of the gallium nitride based semiconductor. The p-type cladding region comprises a first p-type group III nitride semiconductor layer of an AlGaN layer anisotropically-strained, and a second p-type group III nitride semiconductor layer of material different from the AlGaN layer. The first p-type group III nitride semiconductor layer is provided between the second p-type group III nitride semiconductor layer and the active layer. The AlGaN layer has the largest bandgap in the p-type cladding region. The second p-type group III nitride semiconductor layer has a resistivity lower than the first p-type group III nitride semiconductor layer.

Abstract: Provided is a III-nitride semiconductor laser diode which is capable of lasing at a low threshold. A support base has a semipolar or nonpolar primary surface. The c-axis Cx of a III-nitride is inclined relative to the primary surface. An n-type cladding region and a p-type cladding region are provided above the primary surface of the support base. A core semiconductor region is provided between the n-type cladding region and the p-type cladding region. The core semiconductor region includes a first optical guide layer, an active layer, and a second optical guide layer. The active layer is provided between the first optical guide layer and the second optical guide layer. The thickness of the core semiconductor region is not less than 0.5 ?m. This structure allows the confinement of light into the core semiconductor region without leakage of light into the support base, and therefore enables reduction in threshold current.

Abstract: A method for producing a semiconductor element includes a step of forming a multiple quantum well in which a GaSb layer and an InAs layer are alternately stacked on a GaSb substrate by MOVPE, wherein, in the step of forming a multiple quantum well, an InSb film is formed on at least one of a lower-surface side and an upper-surface side of the InAs layer so as to be in contact with the InAs layer.

Abstract: A laser diode device includes: a semiconductor substrate including a semi-polar surface, the semiconductor substrate being formed of a hexagonal III-nitride semiconductor; an epitaxial layer including a light emitting layer, the epitaxial layer being formed on the semi-polar surface of the semiconductor substrate, and the epitaxial layer including a ridge section; a first electrode formed on a top surface of the ridge section; an insulating layer covering the epitaxial layer in an adjacent region of the ridge section and a side surface of the ridge section, the insulating layer covering part or all of side surfaces of the first electrode continuously from the epitaxial layer; a pad electrode formed to cover a top surface of the first electrode and the insulating layer, the pad electrode being electrically connected to the first electrode; and a second electrode formed on a surface, of the semiconductor substrate, opposite to the semi-polar surface.

Abstract: A semiconductor device includes a supporting substrate, a conductive layer placed on the supporting substrate, and at least one group III nitride semiconductor layer placed on the conductive layer. Of the group III nitride semiconductor layers, a conductive-layer-neighboring group III nitride semiconductor layer has n type conductivity, dislocation density of at most 1×107 cm?2, and oxygen concentration of at most 5×1018 cm?3. Thus, an n-down type device having a semiconductor layer of high crystallinity can be provided.

Abstract: A group III nitride semiconductor light emitting device includes an n-type cladding layer and a p-type cladding layer on a primary surface of a substrate, the c-axes of which tilt relative to the normal axis of the primary surface of the substrate. The p-type cladding layer is doped with a p-type dopant providing an acceptor level, and the p-type cladding layer contains an n-type impurity providing a donor level. An active layer is disposed between the n-type cladding layer and the p-type cladding layer. The concentration of the p-type dopant is greater than that of the n-type impurity. The difference (E(BAND)?E(DAP)) between the energy E(BAND) of a band-edge emission peak value in the photoluminescence spectrum of the p-type cladding layer and the energy E(DAP) of a donor-acceptor pair emission peak value in the photoluminescence spectrum is not more than 0.42 electron volts.

Abstract: A group III nitride semiconductor light-emitting device comprises an n-type gallium nitride-based semiconductor layer, a first p-type AlXGa1-XN (0?X<1) layer, an active layer including an InGaN layer, a second p-type AlYGa1-YN (0?Y?X<1) layer, a third p-type AlZGa1-XN layer (0?Z?Y?X<1), and a p-electrode in contact with the third p-type AlZGa1-ZN layer. The active layer is provided between the n-type gallium nitride-based semiconductor layer and the first p-type AlXGa1-XN layer. The second p-type AlYGa1-YN (0?Y?X<1) layer is provided on the first p-type AlXGa1-XN layer. The p-type dopant concentration of the second p-type AlYGa1-YN layer is greater than the p-type dopant concentration of the first p-type AlXGa1-XN layer. The third p-type AlZGa1-ZN layer (0?Z?Y?X<1) is provided on the second p-type AlYGa1-YN layer. The p-type dopant concentration of the second p-type AlYGa1-YN layer is greater than a p-type dopant concentration of the third p-type AlZGa1-ZN layer.

Abstract: A light emitting device having a relatively simple configuration is provided that emits stable light having a plurality of wavelengths. The light emitting device 1 comprises, in sequence, a composite substrate 3 and a gallium nitride-based semiconductor layer 5 including a light emitting layer 9. The composite substrate 3 includes a base 19 and a gallium nitride layer, the gallium nitride-based semiconductor layer 5 being disposed on a principal surface of the gallium nitride layer, the angle ? defined by the c-axis of the gallium nitride layer and a normal line N1 to the principal surface S1 of the gallium nitride layer ranging from 50 to 130 degrees, the light emitting layer 9 emitting light with an absolute value of the degree of polarization of 0.2 or more, the base 19 containing a fluorescent material that emits a fluorescent light component induced by irradiation of a light component emitted from the light emitting layer 9.

Abstract: Provided is a Group III nitride semiconductor device, which comprises an electrically conductive substrate including a primary surface comprised of a first gallium nitride based semiconductor, and a Group III nitride semiconductor region including a first p-type gallium nitride based semiconductor layer and provided on the primary surface. The primary surface of the substrate is inclined at an angle in the range of not less than 50 degrees, and less than 130 degrees from a plane perpendicular to a reference axis extending along the c-axis of the first gallium nitride based semiconductor, an oxygen concentration Noxg of the first p-type gallium nitride based semiconductor layer is not more than 5×1017 cm?3, and a ratio (Noxg/Npd) of the oxygen concentration Noxg to a p-type dopant concentration Npd of the first p-type gallium nitride based semiconductor layer is not more than 1/10.

Abstract: A nitride-based semiconductor light-emitting element LE1 or LD1 has: a gallium nitride substrate 11 having a principal surface 11a which makes an angle ?, in the range 40° to 50° or in the range more than 90° to 130°, with the reference plane Sc perpendicular to the reference axis Cx extending in the c axis direction; an n-type gallium nitride-based semiconductor layer 13; a second gallium nitride-based semiconductor layer 17; and a light-emitting layer 15 including a plurality of well layers of InGaN and a plurality of barrier layers 23 of a GaN-based semiconductor, wherein the direction of piezoelectric polarization of the plurality of well layers 21 is the direction from the n-type gallium nitride-based semiconductor layer 13 toward the second gallium nitride-based semiconductor layer 17.

Abstract: For a nitride semiconductor light emitting device, a c-axis vector of hexagonal GaN of a support substrate is inclined to an X-axis direction with respect to a normal axis Nx normal to a primary surface. In a semiconductor region an active layer, a first gallium nitride-based semiconductor layer, an electron block layer, and a second gallium nitride-based semiconductor layer are arranged along the normal axis on the primary surface of the support substrate. A p-type cladding layer is comprised of AlGaN, and the electron block layer is comprised of AlGaN. The electron block layer is subject to tensile strain in the X-axis direction. The first gallium nitride-based semiconductor layer is subject to compressive strain in the X-axis direction. The misfit dislocation density at an interface is smaller than that at an interface. A barrier to electrons at the interface is raised by piezoelectric polarization.

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: A nitride semiconductor light-emitting device has a semiconductor ridge, and includes a first inner-layer between an active layer and an n-type cladding and a second inner-semiconductor layer between the active layer and a p-type cladding. The first inner-layer, active layer and second inner-layer constitute a core-region. The n-type cladding, core-region and p-type cladding constitute a waveguide-structure. The active layer and the first inner-layer constitute a first heterojunction inclined at an angle greater than zero with respect to a reference plane of the c-plane of the nitride semiconductor of the n-type cladding. Piezoelectric polarization of the well layer is oriented in a direction from the p-type cladding toward the n-type cladding. The second inner-layer and InGaN well layer constitute a second heterojunction. A distance between the ridge bottom and the second heterojunction is 200 nm or less. The ridge includes a third heterojunction between the second inner-layer and the p-type cladding.

Abstract: A nitride semiconductor laser includes an electrically conductive support substrate with a primary surface of a gallium nitride based semiconductor, an active layer provided above the primary surface, and a p-type cladding region provided above the primary surface. The primary surface is inclined relative to a reference plane perpendicular to a reference axis extending in a direction of the c-axis of the gallium nitride based semiconductor. The p-type cladding region includes first and second p-type Group III nitride semiconductor layers. The first p-type semiconductor layer comprises an InAlGaN layer including built-in anisotropic strain. The second p-type semiconductor layer comprises semiconductor different from material of the InAlGaN layer. The first nitride semiconductor layer is provided between the second p-type semiconductor layer and the active layer. The second p-type semiconductor layer has a resistivity lower than that of the first p-type semiconductor layer.

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 nitride-based semiconductor light-emitting element LE1 or LD1 has: a gallium nitride substrate 11 having a principal surface 11a which makes an angle ?, in the range 40° to 50° or in the range more than 90° to 130°, with the reference plane Sc perpendicular to the reference axis Cx extending in the c axis direction; an n-type gallium nitride-based semiconductor layer 13; a second gallium nitride-based semiconductor layer 17; and a light-emitting layer 15 including a plurality of well layers of InGaN and a plurality of barrier layers 23 of a GaN-based semiconductor, wherein the direction of piezoelectric polarization of the plurality of well layers 21 is the direction from the n-type gallium nitride-based semiconductor layer 13 toward the second gallium nitride-based semiconductor layer 17.

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 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.