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 group III nitride crystal substrate is provided in which a uniform distortion at a surface layer of the crystal substrate represented by a value of |d1?d2|/d2 obtained from a plane spacing d1 at the X-ray penetration depth of 0.3 ?m and a plane spacing d2 at the X-ray penetration depth of 5 ?m is equal to or lower than 1.9×10?3, and the main surface has a plane orientation inclined in the <10-10> direction at an angle equal to or greater than 10° and equal to or smaller than 80° with respect to one of (0001) and (000-1) planes of the crystal substrate. A group III nitride crystal substrate suitable for manufacturing a light emitting device with a blue shift of an emission suppressed, an epilayer-containing group III nitride crystal substrate, a semiconductor device and a method of manufacturing the same can thereby be provided.

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 method of forming a p-type gallium nitride based semiconductor without activation annealing is provided, and the method can provide a gallium nitride based semiconductor doped with a p-type dopant. A GaN semiconductor region 17 containing a p-type dopant is formed on a supporting base 13 in a reactor 10. An organometallic source and ammonia are supplied to the reactor 10 to grow the GaN semiconductor layer 17 on a GaN semiconductor layer 15. The GaN semiconductor is doped with a p-type dopant. Examples of the p-type dopant include magnesium. After the GaN semiconductor regions 15 and 17 are grown, an atmosphere 19 containing at least one of monomethylamine and monoethylamine is prepared in the reactor 10. After the atmosphere 19 is prepared, a substrate temperature is decreased from the growth temperature of the GaN semiconductor region 17. When the substrate temperature is lowered to room temperature after this film formation, a p-type GaN semiconductor 17a and an epitaxial wafer E has been fabricated.

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: Provided is a nitride electronic device having a structure that allows the reduction of leakage by preventing the carrier concentration from increasing in a channel layer. An inclined surface and a primary surface of a semiconductor stack extend along first and second reference planes R1, R2, respectively. The primary surface of the stack is inclined at an angle ranging from 5 to 40 degrees with respect to a reference axis indicating a c-axis direction of hexagonal group III nitride. An axis normal to the plane R1 and the axis form an angle smaller than the angle an axis normal to the plane R2 and the axis form. The oxygen concentration of the channel layer is lower than 1×1017 cm?3. It becomes possible to avoid increase in carrier concentration of the channel layer caused by the oxygen addition, thereby reducing leakage current via the channel layer in the transistor.

Abstract: A group III nitride crystal substrate is provided in which a uniform distortion at a surface layer of the crystal substrate represented by a value of |d1 ?d2 |/d2 obtained from a plane spacing d1 at the X-ray penetration depth of 0.3 ?m and a plane spacing d2 at the X-ray penetration depth of 5 ?m is equal to or lower than 1.9 ×10?3, and the main surface has a plane orientation inclined in the <10-10> direction at an angle equal to or greater than 10° and equal to or smaller than 80° with respect to one of (0001) and (000-1) planes of the crystal substrate. A group III nitride crystal substrate suitable for manufacturing a light emitting device with a blue shift of an emission suppressed, an epilayer-containing group III nitride crystal substrate, a semiconductor device and a method of manufacturing the same can thereby be provided.

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: 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 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: A group III nitride composite substrate includes a support substrate and a group III nitride film. A ratio st/mt of a standard deviation st of the thickness of the group III nitride film, to a mean value mt of the thickness thereof is 0.001 or more and 0.2 or less, and a ratio so/mo of a standard deviation so of an absolute value of an off angle between a main surface of the group III nitride film and a plane of a predetermined plane orientation, to a mean value mo of the absolute value of the off angle thereof is 0.005 or more and 0.6 or less. Accordingly, there is provided a low-cost and large-diameter group III nitride composite substrate including a group III nitride film having a large thickness, a small thickness variation, and a high crystal quality.

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 III-nitride semiconductor laser device including: a laser structure including a support base and a semiconductor region, the support base including a hexagonal III-nitride semiconductor and having a semipolar primary surface, and the semiconductor region being provided on the semipolar primary surface of the support base; and an electrode provided on the semiconductor region of the laser structure, the semiconductor region including a first cladding layer, a second cladding layer, and an active layer.

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: 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.