摘要:
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.
摘要:
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 ALPHA with respect to the 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 a plurality of GaN-based semiconductor layers. The reference axis is inclined at a first angle ALPHA1 in the range of not less than 10 degrees, and less than 80 degrees from the c-axis of the III-nitride semiconductor toward a first crystal axis, either one of the m-axis and a-axis. The reference axis is inclined at a second angle ALPHA2 in the range of not less than −0.30 degrees and not more than +0.30 degrees from the c-axis of the III-nitride semiconductor toward a second crystal axis, the other of the m-axis and a-axis. The predetermined angle, the first angle, and the second angle have a relation of ALPHA=(ALPHA12+ALPHA22)1/2. 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.
摘要:
In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle α from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle α 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.
摘要:
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. A GaN based semiconductor layer 23 of an oxygen concentration of 5×1016 cm−3 or more provides an active layer 17 with an excellent crystal quality, and the active layer 17 is grown on the primary surface of the GaN based semiconductor layer 23.
摘要:
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. The c-axis of the hexagonal group-III nitride semiconductor of the support base tilts at a finite angle ALPHA with respect to a normal axis toward an a-axis of the hexagonal group-III nitride semiconductor. The laser structure includes first and second fractured faces intersecting with an a-n plane defined by the normal axis and the a-axis of the hexagonal group-III nitride semiconductor. The laser cavity of the group-III nitride semiconductor laser device includes the first and second fractured faces. The laser structure includes first and second surfaces and the first surface is opposite to the second surface, and each of the first and second fractured faces extends from an edge of the first surface to an edge of the second surface.
摘要:
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
摘要翻译:III族氮化物衬底具有半极性主表面。 第一包层具有第一导电类型,并且包括含铝的III族氮化物。 第一包层设置在基板上。 在第一包层上设置有源层。 第二包层具有第二导电类型,并且包括含铝的III族氮化物。 第二包覆层设置在有源层上。 在第一包层和有源层之间和/或第二包层和有源层之间设置光导层。 光引导层包括包含In x Ga 1-x N(0&amp; n 1; x1 <1)的第一层和包含In x Ga 1-x 2 N(x 1
摘要:
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.
摘要:
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.
摘要:
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
摘要:
In the nitride based semiconductor optical device LE1, the strained well layers 21 extend along a reference plane SR1 tilting at a tilt angle α from the plane that is orthogonal to a reference axis extending in the direction of the c-axis. The tilt angle α 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.